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     docName="draft-ietf-ippm-metric-registry-24" number="8911"
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  <front>
    <title abbrev="Registry for Performance Metrics">Registry for Performance
    Metrics</title>
    <seriesInfo name="RFC" value="8911"/>

    <author fullname="Marcelo Bagnulo" initials="M." surname="Bagnulo">
      <organization abbrev="UC3M">Universidad Carlos III de
      Madrid</organization>
      <address>
        <postal>
          <street>Av. Universidad 30</street>
          <city>Leganes</city>
          <region>Madrid</region>
          <code>28911</code>

          <country>SPAIN</country>
          <country>Spain</country>
        </postal>
        <phone>34 91 6249500</phone>
        <email>marcelo@it.uc3m.es</email>
        <uri>http://www.it.uc3m.es</uri>
      </address>
    </author>
    <author fullname="Benoit Claise" initials="B." surname="Claise">
      <organization abbrev="Cisco Systems, Inc.">Cisco Systems,
      Inc.</organization>
      <address>
        <postal>
          <street>De Kleetlaan 6a b1</street>
          <city>1831 Diegem</city>
          <country>Belgium</country>
        </postal>
        <email>bclaise@cisco.com</email>
      </address>
    </author>
    <author fullname="Philip Eardley" initials="P." surname="Eardley">
      <organization abbrev="BT">BT</organization>
      <address>
        <postal>
          <street>Adastral Park, Martlesham Heath</street>
          <city>Ipswich</city>

          <country>ENGLAND</country>
          <country>United Kingdom</country>
        </postal>
        <email>philip.eardley@bt.com</email>
      </address>
    </author>
    <author fullname="Al Morton" initials="A." surname="Morton">
      <organization abbrev="AT&amp;T Labs">AT&amp;T Labs</organization>
      <address>
        <postal>
          <street>200 Laurel Avenue South</street>

          <city>Middletown, NJ</city>

          <country>USA</country>
          <city>Middletown</city>
          <region>NJ</region>
          <code>07748</code>
          <country>United States of America</country>
        </postal>
        <email>acmorton@att.com</email>
      </address>
    </author>
    <author fullname="Aamer Akhter" initials="A." surname="Akhter">
      <organization abbrev="Consultant">Consultant</organization>
      <address>
        <postal>
          <street>118 Timber Hitch</street>
          <city>Cary</city>
          <region>NC</region>
          <code/>

          <country>USA</country>
          <country>United States of America</country>
        </postal>
        <email>aakhter@gmail.com</email>
      </address>
    </author>
    <date day="9" month="March" month="October" year="2020"/>

<keyword>IPPM</keyword>
<keyword>Loss</keyword>
<keyword>Delay</keyword>

    <abstract>
      <t>This document defines the format for the IANA Performance Metrics
      Registry. This document also gives a set of guidelines for Registered
      Performance Metric requesters and reviewers.</t>
    </abstract>
  </front>
  <middle>
    <section title="Introduction"> numbered="true" toc="default">
      <name>Introduction</name>
      <t>The IETF specifies and uses Performance Metrics of protocols and
      applications transported over its protocols. Performance metrics Metrics are
      an important part of network operations using IETF protocols, and <xref
      target="RFC6390"/> target="RFC6390" format="default"/> specifies guidelines for their development.</t>
      <t>The definition and use of Performance Metrics in the IETF has have been
      fostered in various working groups (WG), most (WGs). Most notably: <list>
          <t>The </t>
      <ul empty="false" spacing="normal">
        <li>The "IP Performance Metrics" (IPPM) WG is the WG primarily
          focusing on Performance Metrics definition at the IETF.</t>

          <t>The IETF.</li>
        <li>The "Benchmarking Methodology" WG (BMWG) defines many Performance
          Metrics for use in laboratory benchmarking of inter-networking
          technologies.</t>

          <t>The internetworking
          technologies.</li>
        <li>The "Metric Blocks for use with RTCP's Extended Report Framework"
          (XRBLOCK) WG (concluded) specified many Performance Metrics related
          to "RTP Control Protocol Extended Reports (RTCP XR)" <xref
          target="RFC3611"/>, target="RFC3611" format="default"/>, which establishes a framework to allow new
          information to be conveyed in RTCP, supplementing the original
          report blocks defined in "RTP: A Transport Protocol for Real-Time
          Applications",
          Applications" <xref target="RFC3550"/>.</t>

          <t>The target="RFC3550" format="default"/>.</li>
        <li>The "IP Flow Information eXport" (IPFIX) concluded WG (concluded) specified
          an IANA Internet Assigned Numbers Authority (IANA) process for new
          Information Elements. Some Performance
          Metrics related Information Elements related to Performance
          Metrics are proposed on a regular
          basis.</t>

          <t>The basis.</li>
        <li>The "Performance Metrics for Other Layers" (PMOL) a concluded WG (concluded)
          defined some Performance Metrics related to Session Initiation
          Protocol (SIP) voice quality <xref target="RFC6035"/>.</t>
        </list></t> target="RFC6035" format="default"/>.</li>
      </ul>
      <t>It is expected that more Performance Metrics will be defined in the
      future,
      future -- not only IP-based metrics, metrics but also metrics which that are
      protocol-specific
      protocol specific and application-specific.</t> application specific.</t>
      <t>Despite the importance of Performance Metrics, there are two related
      problems for the industry. First, industry:</t>

      <ul empty="false" spacing="normal">
        <li>First, ensuring that when one party requests that
      another party to measure (or report or in some way act on) a particular
      Performance Metric, then both parties have exactly the same
      understanding of what Performance Metric is being referred to. Second, to.</li>
        <li>Second,
      discovering which Performance Metrics have been specified, to avoid
      developing a new Performance Metric that is very similar, similar but not quite
      inter-operable. These
      interoperable.</li>
      </ul>

     <t>These problems can be addressed by creating a registry Registry
      of performance metrics. The usual way in which the IETF organizes
      registries is Performance Metrics with the Internet Assigned Numbers Authority (IANA), and there
      is currently no
      (IANA).   As such, this document defines the new IANA Performance
      Metrics Registry maintained by the IANA.</t>

      <t>This document requests that Registry.</t>

      <t>Per this document, IANA create has created and maintain a now maintains the Performance
      Metrics Registry, according to the maintenance procedures and the
      Performance Metrics Registry
      format defined in this memo. the sections below. The resulting
      Performance Metrics Registry is for use by the IETF and others. Although
      the Registry formatting specifications herein are primarily for registry Registry
      creation by IANA, any other organization that wishes to create a
      performance metrics registry
      Performance Metrics Registry may use the same formatting specifications
      for their purposes. The authors make no guarantee of the registry Registry
      format's applicability to any possible set of Performance Metrics
      envisaged by other organizations, but we encourage others to apply it. In
      the remainder of this document, unless we explicitly say otherwise, we
      will refer to the IANA-maintained Performance Metrics Registry as simply
      the Performance Metrics Registry.</t>
    </section>
    <section title="Terminology"> numbered="true" toc="default">
      <name>Terminology</name>
       <t>The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
      "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", "<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>",
       "<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>",
       "<bcp14>SHALL NOT</bcp14>", "<bcp14>SHOULD</bcp14>",
       "<bcp14>SHOULD NOT</bcp14>",
       "<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>",
       "<bcp14>MAY</bcp14>", and
      "OPTIONAL" "<bcp14>OPTIONAL</bcp14>" in this document
       are to be interpreted as described in BCP 14 BCP&nbsp;14
       <xref target="RFC2119"/> <xref target="RFC8174"/> when, and only
       when, they appear in all capitals, as shown here.</t>

      <!--      <t>The terms Performance Metric is
      defined in <xref target="RFC6390"/>, and copied over in this document
      for the readers convenience.</t>
-->

      <t><list style="hanging">
          <t hangText="Performance Metric:">A Performance Metric is a

      <dl newline="false" spacing="normal">
        <dt>Performance Metric:</dt>
        <dd>A quantitative measure of performance, targeted to an IETF-specified
          protocol or targeted to an application transported over an
          IETF-specified protocol. Examples of Performance Metrics are the FTP
          response time for a complete file download, the DNS response Response time to
          resolve the IP address(es), a database logging time, etc. This
          definition is consistent with the definition of a metric in <xref
          target="RFC2330"/>
          target="RFC2330" format="default"/> and broader than the definition
          of performance
          metric a Performance Metric in <xref target="RFC6390"/>.</t>

          <t hangText="Registered Performance Metric:">A Registered target="RFC6390" format="default"/>.</dd>
        <dt>Registered Performance Metric is a Metric:</dt>
        <dd>A Performance Metric expressed as an entry in
          the Performance Metrics Registry, administered by IANA. Such a
          performance metric
          Performance Metric has met all of the registry Registry review criteria defined
          in this document in order to be included in the registry.</t>

          <t hangText="Performance Registry.</dd>
        <dt>Performance Metrics Registry:">The Registry:</dt>
        <dd>The IANA registry Registry
          containing Registered Performance Metrics.</t>

          <t hangText="Proprietary Registry:">A Metrics.</dd>
        <dt>Proprietary Registry:</dt>
        <dd>A set of metrics that are
          registered in a proprietary registry, Registry, as opposed to the Performance
          Metrics Registry.</t>

          <t hangText="Performance Metrics Experts:">The Performance Registry.</dd>
        <dt>Performance Metrics
          Experts is a Experts:</dt>
        <dd>A group of designated experts <xref target="RFC8126"/> target="RFC8126" format="default"/>
          selected by the IESG to validate the Performance Metrics before
          updating the Performance Metrics Registry. The Performance Metrics
          Experts work closely with IANA.</t>

          <!--          <t hangText="Performance Metrics Directorate:">The Performance
          Metrics Directorate is a directorate that provides guidance for
          Performance Metrics development in the IETF. The Performance Metrics
          Directorate should be composed of experts in the performance
          community, potentially selected from the IP Performance Metrics
          (IPPM), Benchmarking Methodology (BMWG), and Performance Metrics for
          Other Layers (PMOL) WGs.</t>
-->

          <t hangText="Parameter:">A Parameter is an IANA.</dd>
        <dt>Parameter:</dt>
        <dd>An input factor defined as a
          variable in the definition of a Performance Metric. A Parameter is a
          numerical or other specified factor forming one of a set that
          defines a metric or sets the conditions of its operation. All
          Parameters must be known in order to make a measurement using a
          metric and interpret the results. There are two types of Parameters:
          Fixed and Run-time parameters. Runtime. For the Fixed Parameters, the value
          of the variable is specified in the Performance Metrics Registry
          entry and different Fixed Parameter values results in different
          Registered Performance Metrics. For the Run-time Runtime Parameters, the
          value of the variable is defined when the metric measurement method Metric Measurement Method
          is executed and a given Registered Performance Metric supports
          multiple values for the parameter. Parameter. Although Run-time Runtime Parameters do
          not change the fundamental nature of the Performance Metric's
          definition, some have substantial influence on the network property
          being assessed and interpretation of the results. <list>
              <t>Note: results.</dd>
      </dl>

    <aside><t>Note: Consider the case of packet loss in the following two
              Active Measurement Method cases. The first case is packet loss
              as background loss where the Run-time Runtime Parameter set includes a
              very sparse Poisson stream, stream and only characterizes the times
              when packets were lost. Actual user streams likely see much
              higher loss at these times, due to tail drop or radio errors.
              The second case is packet loss ratio as inverse the complimentary
              probability of throughput delivery ratio where
              the Run-time Runtime Parameter set includes a very dense, bursty stream,
              and characterizes the loss experienced by a stream that
              approximates a user stream. These are both "loss "Loss metrics", but
              the difference in interpretation of the results is highly
              dependent on the Run-time Runtime Parameters (at least), to the extreme
              where we are actually using loss ratio to infer its compliment:
              delivered throughput.</t>
            </list></t>

          <t hangText="Active complimentary
              probability: delivery ratio.</t></aside>

       <dl newline="false" spacing="normal">
        <dt>Active Measurement Method:">Methods Methods:</dt>
        <dd>Methods of Measurement
          conducted on traffic which that serves only the purpose of measurement
          and is generated for that reason alone, and whose traffic
          characteristics are known a priori. The complete definition of
          Active Methods is specified in section 3.4 of<xref
          target="RFC7799"/>. <xref target="RFC7799" sectionFormat="of" section="3.4"/>. Examples of Active Measurement Methods are the
          measurement methods
          Measurement Methods for the One way one-way delay metric defined in <xref
          target="RFC7679"/>
          target="RFC7679" format="default"/> and the one for round trip round-trip delay metric defined in <xref
          target="RFC2681"/>.</t>

          <t hangText="Passive target="RFC2681" format="default"/>.</dd>
        <dt>Passive Measurement Method:">Methods Methods:</dt>
        <dd>Methods of Measurement
          conducted on network traffic, generated by either from the (1)&nbsp;the end
          users or
          from network (2)&nbsp;network elements that would exist regardless of whether the
          measurement was being conducted or not. The complete definition of
          Passive Methods is specified in section 3.6 of <xref
          target="RFC7799"/>. target="RFC7799" sectionFormat="of" section="3.6"/>. One characteristic of Passive Measurement
          Methods is that sensitive information may be observed, and observed and, as a
          consequence, stored in the measurement system.</t>

          <t hangText="Hybrid system.</dd>
        <dt>Hybrid Measurement Method:">Hybrid Methods are Methods Methods:</dt>
        <dd>Methods of Measurement that use a combination of Active Methods and Passive
          Methods, to assess Active Metrics, Passive Metrics, or new metrics
          derived from the a priori a&nbsp;priori knowledge and observations of the stream
          of interest. The complete definition of Hybrid Methods is specified
          in section 3.8 of <xref target="RFC7799"/>.<!--		  Some examples include IPFIX <xref target="RFC4656"/>, PSAMP. [RFC 5470], [RFC 5476]--></t>
        </list></t> target="RFC7799" sectionFormat="of" section="3.8"/>.
        </dd>
      </dl>
    </section>
    <section title="Scope"> numbered="true" toc="default">
      <name>Scope</name>
      <t>This document is intended for two different audiences:</t>

      <t><list style="numbers">
          <t>For
      <ol spacing="normal" type="1">
        <li>For those defining new Registered Performance Metrics, it
          provides specifications and best practices to be used in deciding
          which Registered Performance Metrics are useful for a measurement
          study, instructions for writing the text for each column of the
          Registered Performance Metrics, and information on the supporting
          documentation required for the new Performance Metrics Registry
          entry
          Entry (up to and including the publication of one or more immutable
          documents such as an RFC).</t>

          <t>For RFC).</li>
        <li>For the appointed Performance Metrics Experts and for IANA
          personnel administering the new IANA Performance Metrics Registry,
          it defines a set of acceptance criteria against which these proposed
          Registered Performance Metrics should be evaluated.</t>
        </list></t> evaluated.</li>
      </ol>
      <t>In addition, this document may be useful for other organizations who
      are defining a Performance Metric registry Metrics Registry of their own, own and may re-use reuse
      the features of the Performance Metrics Registry defined in this
      document.</t>
      <t>This Performance Metrics Registry is applicable to Performance
      Metrics issued from Active Measurement, Passive Measurement, and any
      other form of Performance Metric. This registry Registry is designed to encompass
      Performance Metrics developed throughout the IETF and especially for the
      technologies specified in the following working groups: IPPM, XRBLOCK,
      IPFIX, and BMWG. This document analyzes a prior attempt to set up a
      Performance Metrics Registry, Registry and the reasons why this design was
      inadequate <xref target="RFC6248"/>. target="RFC6248" format="default"/>. Finally, this document gives a set
      of guidelines for requesters and expert reviewers Expert Reviewers of candidate
      Registered Performance Metrics.</t>

      <t>This document makes no attempt to populate

      <t><xref target="RFC8912" format="default"/> populates the Performance Metrics new Registry
      with initial entries; the related memo <xref
      target="I-D.ietf-ippm-initial-registry"/> proposes the initial set of
      regsitry entries.</t>
    </section>

    <section title="Motivation numbered="true" toc="default">
      <name>Motivations for a the Performance Metrics Registry"> Registry</name>
      <t>In this section, we detail several motivations for the Performance
      Metrics Registry.</t>
      <section title="Interoperability"> numbered="true" toc="default">
        <name>Interoperability</name>
        <t>As with any IETF registry, Registry, the primary intention is to manage the
        registration of identifiers Identifiers for use within one or more protocols. In
        the particular case of the Performance Metrics Registry, there are two
        types of protocols that will use the Performance Metrics in the
        Performance Metrics Registry during their operation (by referring to
        the Index index values): <list style="symbols">
            <t>Control protocol: This </t>

          <dl newline="false" spacing="normal">
           <dt>Control protocol:</dt><dd>This type of protocol is used to allow one
            entity to request that another entity to perform a measurement using a
            specific metric defined by the Performance Metrics Registry. One
            particular example is the LMAP Large-scale Measurement of Broadband
            Performance (LMAP) framework <xref target="RFC7594"/>. target="RFC7594" format="default"/>.
            Using the LMAP terminology, the Performance Metrics Registry is
            used in the LMAP Control protocol Protocol to allow a Controller to
            schedule a measurement task for one or more Measurement Agents. In
            order to enable this use case, the entries of in the Performance
            Metrics Registry must be sufficiently defined to allow a
            Measurement Agent implementation to trigger a specific measurement
            task upon the reception of a control protocol message. This
            requirement heavily constrains the type types of entries that are
            acceptable for the Performance Metrics Registry. <!--Further considerations about
            this are captured in the Guidelines for metric registry
            allocations (cross reference to another section of this document
            or to a different document).--></t>

            <t>Report protocol: This Registry.</dd>
          <dt>Report protocol:</dt><dd>This type of protocol is used to allow an
            entity to report measurement results to another entity. By
            referencing to a specific Performance Metrics Registry, it is
            possible to properly characterize the measurement result data
            being reported. Using the LMAP terminology, the Performance
            Metrics Registry is used in the LMAP Report protocol Protocol to allow a
            Measurement Agent to report measurement results to a
            Collector.</t>
          </list>
            Collector.</dd>
</dl>
        <t> It should be noted that the LMAP framework explicitly allows
        for using not only the IANA-maintained Performance Metrics Registry
        but also other registries containing Performance Metrics, i.e.,
        either (1)&nbsp;registries defined by other organizations or private ones. (2)&nbsp;private registries. However, others who
        are creating Registries registries to be used in the context of an LMAP framework
        are encouraged to use the Registry format defined in this document,
        because this makes it easier for developers of LMAP Measurement Agents
        (MAs)
        to programmatically use information found in those other
        Registries'
        registries' entries.</t>
      </section>
      <section title="Single point numbered="true" toc="default">
        <name>Single Point of reference Reference for Performance Metrics"> Metrics</name>
        <t>A Performance Metrics Registry serves as a single point of
        reference for Performance Metrics defined in different working groups
        in the IETF. As we mentioned earlier, there are several WGs working groups that
        define Performance Metrics in the IETF IETF, and it is hard to keep track of
        all of them. This results in multiple definitions of similar Performance
        Metrics that attempt to measure the same phenomena but in slightly
        different (and incompatible) ways. Having a registry Registry would allow the
        IETF community and others to have a single list of relevant
        Performance Metrics defined by the IETF (and others, where
        appropriate). The single list is also an essential aspect of
        communication about Performance Metrics, where different entities that
        request measurements, execute measurements, and report the results can
        benefit from a common understanding of the referenced Performance
        Metric.</t>
      </section>
      <section title="Side benefits"> numbered="true" toc="default">
        <name>Side Benefits</name>
        <t>There are a couple of side benefits of having such a registry. Registry.
        First, the Performance Metrics Registry could serve as an inventory of
        useful and used Performance Metrics, Metrics that are normally supported by
        different implementations of measurement agents. Measurement Agents. Second, the results
        of measurements using the Performance Metrics should be comparable
        even if they are performed by different implementations and in
        different networks, as the Performance Metric is properly defined. BCP
        176 <xref target="RFC6576"/> target="RFC6576" format="default"/> examines whether the results produced by
        independent implementations are equivalent in the context of
        evaluating the completeness and clarity of metric specifications. This
        <xref target="RFC6576"/> is another BCP <xref target="RFC2026"/> that defines the standards track Standards Track advancement testing for (active) (Active) IPPM
        metrics,
        Metrics, and the same process will likely suffice to determine whether
        Registered Performance Metrics are sufficiently well specified to
        result in comparable (or equivalent) results. Registered Performance
        Metrics which that have undergone such testing SHOULD <bcp14>SHOULD</bcp14> be noted, with a
        reference to the test results.</t>
      </section>
    </section>
    <section title="Criteria anchor="metrics-criteria" numbered="true" toc="default">
      <name>Criteria for Performance Metrics Registration"> Registration</name>
      <t>It is neither possible nor desirable to populate the Performance
      Metrics Registry with all combinations of Parameters of all Performance
      Metrics. The Registered Performance Metrics SHOULD <bcp14>SHOULD</bcp14> be: <list
          style="numbers">
          <t>interpretable </t>
      <ol spacing="normal" type="1">
        <li>Interpretable by the user.</t>

          <t>implementable user.</li>
        <li>Implementable by the software or hardware designer,</t>

          <t>deployable designer.</li>
        <li>Deployable by network operators,</t>

          <t>accurate operators.</li>
        <li>Accurate in terms of producing equivalent results, and for
          interoperability and deployment across vendors,</t>

          <t>Operationally vendors.</li>
        <li>Operationally useful, so that it has significant industry
          interest and/or has seen deployment,</t>

          <t>Sufficiently deployment.</li>
        <li>Sufficiently tightly defined, so that different values for the
          Run-time
          Runtime Parameters does do not change the fundamental nature of the
          measurement, nor
          measurement or change the practicality of its implementation.</t>
        </list>In implementation.</li>
      </ol>
      <t>In essence, there needs to be evidence that a (1)&nbsp;a candidate
      Registered Performance Metric has significant industry interest, interest or has
      seen deployment, deployment and there (2)&nbsp;there is agreement that the candidate Registered
      Performance Metric serves its intended purpose.</t>
    </section>
<!-- start here -->
    <section title="Performance Metric numbered="true" toc="default">
      <name>Performance Metrics Registry: Prior attempt"> Attempt</name>
      <t>There was a previous attempt to define a metric registry Metrics Registry <xref
      target="RFC4148">RFC 4148</xref>.
      target="RFC4148" format="default"></xref>. However, it was
      obsoleted by <xref
      target="RFC6248">RFC 6248</xref> target="RFC6248" format="default"></xref>
      because it was
<!-- Begin DNE -->
"found to be
      insufficiently detailed to uniquely identify IPPM metrics... [there was
      too much] variability possible when characterizing a metric exactly" exactly",
<!-- End DNE -->
      which led to the RFC4148 registry IPPM Metrics Registry defined in <xref target="RFC4148"/> having
<!-- Begin DNE --> "very few users, if any".</t>

      <t>A couple of any." <!-- End DNE --></t>
      <t>Three interesting additional quotes from <xref
      target="RFC6248">RFC 6248</xref> target="RFC6248" format="default"></xref> might help to understand the issues
      related to that registry. <list style="numbers">
          <t>"It </t>
<!-- Begin DNE.  Had to fix second item (and AQed it, since it's a repeat
     of text in the first paragraph of this section). -->
      <ol spacing="normal" type="1">
        <li>"It is not believed to be feasible or even useful to register
          every possible combination of Type P, metric parameters, and Stream
          parameters using the current structure of the IPPM Metrics
          Registry."</t>

          <t>"The
          Registry."</li>
        <li>"The current registry structure has been found to be insufficiently
          detailed to uniquely identify IPPM metrics."</t>

          <t>"Despite metrics."</li>
        <li>"Despite apparent efforts to find current or even future users,
          no one responded to the call for interest in the RFC 4148 registry
          during the second half of 2010."</t>
        </list></t> 2010."</li>
<!-- End DNE -->
      </ol>
      <t>The current approach learns from this by tightly defining each
      Registered Performance Metric with only a few variable (Run-time) (Runtime)
      Parameters to be specified by the measurement designer, if any. The idea
      is that entries in the Performance Metrics Registry stem from different
      measurement methods which
      Measurement Methods that require input (Run-time) parameters (Runtime) Parameters to set
      factors like source Source and destination Destination addresses (which do not change the
      fundamental nature of the measurement). The downside of this approach is
      that it could result in a large number of entries in the Performance
      Metrics Registry. There is agreement that less is more in this context - --
      it is better to have a reduced set of useful metrics rather than a large
      set of metrics, some with with questionable usefulness.</t>
      <section title="Why this numbered="true" toc="default">
        <name>Why This Attempt Should Succeed"> Succeed</name>
        <t>As mentioned in the previous section, one of the main issues with
        the previous registry Registry was that the metrics contained in the registry Registry
        were too generic to be useful. This document specifies stricter
        criteria for performance metric Performance Metric registration (see section 5), <xref
        target="metrics-criteria"/>) and
        imposes a group of Performance Metrics Experts that will provide
        guidelines to assess if a Performance Metric is properly
        specified.</t>
        <t>Another key difference between this attempt and the previous one is
        that in this case there is at least one clear user for the Performance
        Metrics Registry: the LMAP framework and protocol. Because the LMAP
        protocol will use the Performance Metrics Registry values in its
        operation, this actually helps to determine if a metric is properly
        defined. <!--The following sentence seems very awkward to me.-->In
        defined -- in particular, since we expect that the LMAP control protocol Control Protocol will enable
        a controller Controller to request that a measurement agent to Measurement Agent perform a measurement
        using a given metric by embedding the Performance Metrics Registry
        identifier
        Identifier in the protocol. Such a metric and method are properly
        specified if they are defined well-enough well enough so that it is possible (and
        practical) to implement them in the measurement agent. Measurement Agent. This was the
        failure of the previous attempt: a registry entry Registry Entry with an undefined
        Type-P (section 13 of <xref target="RFC2330">RFC 2330</xref>) (<xref target="RFC2330" sectionFormat="of" section="13"/>) allows
        implementation to be ambiguous.</t>
      </section>
    </section>
    <section anchor="columns"
             title="Definition numbered="true" toc="default">
      <name>Definition of the Performance Metric Registry"> Metrics Registry</name>
      <t>This Performance Metrics Registry is applicable to Performance
      Metrics used for Active Measurement, Passive Measurement, and any other
      form of Performance Measurement. Each category of measurement has unique
      properties, so some of the columns defined below are not applicable for
      a given metric category. In this case, the column(s) SHOULD <bcp14>SHOULD</bcp14> be populated
      with the "NA" "N/A" value (Non (Not Applicable). However, the "NA" "N/A" value MUST NOT <bcp14>MUST NOT</bcp14>
      be used by any metric in the following columns: Identifier, Name, URI,
      Status, Requester, Revision, Revision Date, Description. In the future,
      a new category of metrics could require additional columns, and adding
      new columns is a recognized form of registry Registry extension. The
      specification defining the new column(s) MUST <bcp14>MUST</bcp14> give general guidelines
      for populating the new column(s) for existing entries.</t>
      <t>The columns of the Performance Metrics Registry are defined below.
      The columns are grouped into "Categories" to facilitate the use of the
      registry.
      Registry. Categories are described at the 7.x "Section 7.x" heading level, and columns
      are described at the 7.x.y "Section 7.x.y" heading level. The Figure figure below illustrates this
      organization. An entry (row) therefore gives a complete description of a
      Registered Performance Metric.</t>
      <t>Each column serves as a check-list checklist item and helps to avoid omissions
      during registration and expert review. <figure>
          <artwork><![CDATA[=======================================================================
Legend:
    Registry Expert Review <xref target="RFC8126"/>. </t>
      <t>Registry Categories and Columns are shown below as: in this format:</t>
      <artwork name="" type="" align="left" alt=""><![CDATA[
    Category
    ------------------...
    Column |  Column |...
=======================================================================
]]></artwork>

      <artwork name="" type="" align="left" alt=""><![CDATA[
Summary
------------------------------------------------------------------------
----------------------------------------------------------------
Identifier | Name | URI | Desc. | Reference | Change Controller     | Ver |
           |      |     |       |           | Controller |

Metric Definition
-----------------------------------------
Reference Definition | Fixed Parameters |

Method of Measurement
---------------------------------------------------------------------
Reference | Packet     | Traffic | Sampling     | Run-time Runtime    | Role |
Method    | Stream     | Filter  | Distribution | Parameters |      |
          | Generation |
Output
-----------------------------------------
Type | Reference  | Units | Calibration |
     | Definition |       |             |

Administrative Information
------------------------------------
-------------------------------------
Status |Requester | Rev | Rev.Date Rev. Date |

Comments and Remarks
--------------------

]]></artwork>
        </figure></t>
--------------------]]></artwork>
      <t>There is a blank template of the Registry template provided in
      Section 11
      <xref target="blank-reg-template"/> of this memo.</t>
      <section title="Summary Category">
        <section title="Identifier">
          <t>A numbered="true" toc="default">
        <name>Summary Category</name>
        <section numbered="true" toc="default">
          <name>Identifier</name>
          <t>This entry provides a numeric identifier Identifier for the Registered Performance Metric. This
          identifier MUST
          Identifier <bcp14>MUST</bcp14> be unique within the Performance Metrics
          Registry.</t>
          <t>The Registered Performance Metric unique identifier Identifier is an
          unbounded integer (range 0 to infinity).</t>
          <t>The Identifier 0 should be Reserved. The Identifier values from
          64512 to 65536 are reserved for private or experimental use, and the
          user may encounter overlapping uses.</t>
          <t>When adding newly new Registered Performance Metrics to the
          Performance Metrics Registry, IANA SHOULD <bcp14>SHOULD</bcp14> assign the lowest
          available identifier Identifier to the new Registered Performance Metric.</t>
          <t>If a Performance Metrics Expert providing review determines that
          there is a reason to assign a specific numeric identifier, Identifier, possibly
          leaving a temporary gap in the numbering, then the Performance Metrics
          Expert SHALL <bcp14>SHALL</bcp14> inform IANA of this decision.</t>
        </section>
        <section title="Name"> anchor="name-sec7-1-2" numbered="true" toc="default">
          <name>Name</name>
          <t>As the name Name of a Registered Performance Metric is the first thing
          a potential human implementor implementer will use when determining whether it
          is suitable for their measurement study, it is important to be as
          precise and descriptive as possible. In the future, users will review
          the names Names to determine if the metric they want to measure has
          already been registered, or if a similar entry is available available, as a
          basis for creating a new entry.</t>
          <t>Names are composed of the following elements, separated by an
          underscore character "_":</t>

          <t>MetricType_Method_SubTypeMethod_... Spec_Units_Output</t>

          <t><list style="symbols">
              <t>MetricType: a
        <ul empty="true" spacing="normal">
          <li>MetricType_Method_SubTypeMethod_... Spec_Units_Output</li>
        </ul>

          <dl newline="false" spacing="normal">
              <dt>MetricType:</dt><dd><t>A combination of the directional properties and
              the metric measured, such as and not limited to:<list
                  style="empty">
                  <t>RTDelay (Round to:</t>

<!--
<table anchor="metric-type">
  <thead>
    <tr>
      <th>Name</th>
      <th>Description</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>RTDelay</td>
      <td>Round Trip Delay)</t>

                  <t>RTDNS Delay</td>
    </tr>
    <tr>
      <td>RTDNS</td>
      <td>Response Time Domain Name Service</td>
    </tr>
    <tr>
      <td>RLDNS</td>
      <td>Response Loss Domain Name Service</td>
    </tr>
    <tr>
      <td>OWDelay</td>
      <td>One-Way Delay</td>
    </tr>
    <tr>
      <td>RTLoss</td>
      <td>Round-Trip Loss</td>
    </tr>
    <tr>
      <td>OWLoss</td>
      <td>One-Way Loss</td>
    </tr>
    <tr>
      <td>OWPDV</td>
      <td>One-Way Packet Delay Variation</td>
    </tr>
    <tr>
      <td>OWIPDV</td>
      <td>One-Way Inter-Packet Delay Variation</td>
    </tr>
    <tr>
      <td>OWReorder</td>
      <td>One-Way Packet Reordering</td>
    </tr>
    <tr>
      <td>OWDuplic</td>
      <td>One-Way Packet Duplication</td>
    </tr>
    <tr>
      <td>OWBTC</td>
      <td>One-Way Bulk Transport Capacity</td>
    </tr>
    <tr>
      <td>OWMBM</td>
      <td>One-Way Model-Based Metric</td>
    </tr>
    <tr>
      <td>SPMonitor</td>
      <td>Single-Point Monitor</td>
    </tr>
    <tr>
      <td>MPMonitor</td>
      <td>Multi-Point Monitor</td>
    </tr>
  </tbody>
</table>
-->
<dl>
  <dt>RTDelay:</dt><dd>Round-Trip Delay</dd>
  <dt>RTDNS:</dt><dd>Response Time Domain Name Service</dd>
  <dt>RLDNS:</dt><dd>Response Loss Domain Name Service</dd>
  <dt>OWDelay:</dt><dd>One-Way Delay</dd>
  <dt>RTLoss:</dt><dd>Round-Trip Loss)</dd>
  <dt>OWLoss:</dt><dd>One-Way Loss)</dd>
  <dt>OWPDV:</dt><dd>One-Way Packet Delay Variation)</dd>
  <dt>OWIPDV:</dt><dd>One-Way Inter-Packet Delay Variation</dd>
  <dt>OWReorder:</dt><dd>One-Way Packet Reordering</dd>
  <dt>OWDuplic:</dt><dd>One-Way Packet Duplication</dd>
  <dt>OWBTC:</dt><dd>One-Way Bulk Transport Capacity</dd>
  <dt>OWMBM:</dt><dd>One-Way Model-Based Metric</dd>
  <dt>SPMonitor:</dt><dd>Single-Point Monitor</dd>
  <dt>MPMonitor:</dt><dd>Multi-Point Monitor)</dd>
              </dl>
	    </dd>
<!--
              <ul empty="true" spacing="normal">
                <li>RTDelay (Round-Trip Delay)</li>
                <li>RTDNS (Response Time Domain Name Service)</t>

                  <t>RLDNS Service)</li>
                <li>RLDNS (Response Loss Domain Name Service)</t>

                  <t>OWDelay (One Way Delay)</t>

                  <t>RTLoss (Round Trip Loss)</t>

                  <t>OWLoss (One Way Loss)</t>

                  <t>OWPDV (One Way Service)</li>
                <li>OWDelay (One-Way Delay)</li>
                <li>RTLoss (Round-Trip Loss)</li>
                <li>OWLoss (One-Way Loss)</li>
                <li>OWPDV (One-Way Packet Delay Variation)</t>

                  <t>OWIPDV (One Way Variation)</li>
                <li>OWIPDV (One-Way Inter-Packet Delay Variation)</t>

                  <t>OWReorder (One Way Variation)</li>
                <li>OWReorder (One-Way Packet Reordering)</t>

                  <t>OWDuplic (One Way Reordering)</li>
                <li>OWDuplic (One-Way Packet Duplication)</t>

                  <t>OWBTC (One Way Duplication)</li>
                <li>OWBTC (One-Way Bulk Transport Capacity)</t>

                  <t>OWMBM (One Way Model Based Metric)</t>

                  <t>SPMonitor (Single Point Monitor)</t>

                  <t>MPMonitor Capacity)</li>
                <li>OWMBM (One-Way Model-Based Metric)</li>
                <li>SPMonitor (Single-Point Monitor)</li>
                <li>MPMonitor (Multi-Point Monitor)</t>
                </list></t>

              <t>Method: One Monitor)</li>
              </ul>
-->

              <dt>Method:</dt><dd><t>One of the methods defined in <xref
              target="RFC7799"/>,
              target="RFC7799" format="default"/>, such as and not limited to:<list
                  style="empty">
                  <t>Active
              to:</t>

<!--<table anchor="methods">
  <thead>
    <tr>
      <th>Name</th>
      <th>Description</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>Active</td>
      <td>depends on a dedicated measurement packet stream and observations of
      the stream</td>
    </tr>
    <tr>
      <td>Passive</td>
      <td>depends *solely* on observation of one or more existing packet streams</td>
    </tr>
    <tr>
      <td>HybridType1</td>
      <td>Hybrid Type I observations on one stream that combine both Active
      Methods and Passive Methods as described in <xref target="RFC7799"/>)</td>
    </tr>
    <tr>
      <td>HybridType2</td>
      <td>Hybrid Type II observations on two or more streams that combine both
      Active Methods and Passive Methods as described in <xref target="RFC7799"/></td>
    </tr>
    <tr>
      <td>Spatial</td>
      <td>spatial metric as described in <xref target="RFC5644"/></td>
    </tr>
  </tbody>
</table>
-->

<dl>
  <dt>Active:</dt><dd>depends on a dedicated measurement packet stream
               and observations of the stream)</dd>
	       <dt>Passive:</dt><dd>depends *solely* on observation of one or more
               existing packet streams</dd>
	       <dt>HybridType1:</dt><dd>Hybrid Type I observations on one
	       stream that combine both Active Methods and Passive Methods as
	       described in <xref target="RFC7799"/>)</dd>
               <dt>HybridType2:</dt><dd>Hybrid Type II observations on two or more streams that
               combine both Active Methods and Passive Methods as described in
               <xref target="RFC7799"/>)</dd>
               <dt>Spatial:</dt><dd>spatial metric as described in <xref
             target="RFC5644"/>)</dd>
</dl>

<!--
              <ul empty="true" spacing="normal">
                <li>Active (depends on a dedicated measurement packet stream
                  and observations of the stream)</t>

                  <t>Passive stream)</li>
                <li>Passive (depends *solely* on observation of one or more
                  existing packet streams)</t>

                  <t>HybridType1 (observations streams)</li>
                <li>HybridType1 (Hybrid Type I observations on one stream that
		combine both
                  active
                  Active Methods and passive methods)</t>

                  <t>HybridType2 (observations Passive Methods as described in <xref
		  target="RFC7799"/>)</li>
                <li>HybridType2 (Hybrid Type II observations on two or more
		streams that
                  combine both active Active Methods and passive methods)</t>

                  <t>Spatial (Spatial Metric Passive Methods as described
		  in
                  <xref target="RFC7799"/>)</li>
                <li>Spatial (spatial metric as described in <xref
                target="RFC5644"/>)</li>
	      </ul>
	      </dd>
	     </dl>
-->

<!-- [rfced] [AD*] Section 7.1.2:  RFC 5644 was not listed in the
References section.  Per author feedback during the AUTH state, we
added it to the list of RFC5644)</t>
                </list></t>

              <t>SubTypeMethod: One Normative References.  Please let us know if
you approve.

Currently:
 Spatial (spatial metric as described in [RFC5644])
...
 [RFC5644]  Stephan, E., Liang, L., and A. Morton, "IP Performance
            Metrics (IPPM): Spatial and Multicast", RFC 5644,
            DOI 10.17487/RFC5644, October 2009,
            <https://www.rfc-editor.org/info/rfc5644>. -->

              <dl newline="false" spacing="normal">
              <dt>SubTypeMethod:</dt><dd><t>One or more sub-types subtypes to further describe the
              features of the entry, such as and not limited to:<list
                  style="empty">
                  <t>ICMP (Internet to:</t>

<!-- Reviewer:  Instances of "xxxx" and "RFCXXXX" are DNE. -->
<!-- <table anchor="SubTypeMethod">
  <thead>
    <tr>
      <th>Name</th>
      <th>Description</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>ICMP</td>
      <td>Internet Control Message Protocol)</t>

                  <t>IP (Internet Protocol)</t>

                  <t>DSCPxx (where Protocol</td>
    </tr>
    <tr>
      <td>IP</td>
      <td>Internet Protocol</td>
    </tr>
    <tr>
      <td>DSCPxx</td>
      <td>where xx is replaced by a Diffserv code
                  point)</t>

                  <t>UDP (User point</td>
    </tr>
    <tr>
      <td>UDP</td>
      <td>User Datagram Protocol)</t>

                  <t>TCP (Transport Protocol</td>
    </tr>
    <tr>
      <td>TCP</td>
      <td>Transport Control Protocol)</t>

                  <t>QUIC (QUIC Protocol</td>
    </tr>
    <tr>
      <td>QUIC</td>
      <td>QUIC transport protocol)</t>

                  <t>HS (Hand-Shake, protocol</td>
    </tr>
    <tr>
      <td>HS</td>
      <td>Hand-Shake, such as TCP's 3-way HS)</t>

                  <t>Poisson (Packet HS</td>
    </tr>
    <tr>
      <td>Poisson</td>
      <td>packet generation using Poisson
                  distribution)</t>

                  <t>Periodic (Periodic distribution</td>
    </tr>
    <tr>
      <td>Periodic</td>
      <td>periodic packet generation)</t>

                  <t>SendOnRcv (Sender generation</td>
    </tr>
    <tr>
      <td>SendOnRcv</td>
      <td>sender keeps one packet in-transit in transit by sending when previous packet arrives)</t>

                  <t>PayloadxxxxB (where arrives</td>
    </tr>
    <tr>
      <td>PayloadxxxxB</td>
      <td>where xxxx is replaced by an integer, the number of octets or 8-bit
      Bytes in the Payload))</t>

                  <t>SustainedBurst (Capacity Payload</td>
    </tr>
    <tr>
      <td>SustainedBurst</td>
      <td>capacity test, worst case)</t>

                  <t>StandingQueue (test case</td>
    </tr>
    <tr>
      <td>StandingQueue</td>
      <td>test of bottleneck queue behavior)</t>

                  <t/>
                </list>SubTypeMethod values are separated behavior</td>
    </tr>
  </tbody>
</table>
-->
<dl>
  <dt>ICMP:</dt><dd>Internet Control Message Protocol)</dd>
  <dt>IP:</dt><dd>Internet Protocol)</dd>
  <dt>DSCPxx:</dt><dd>where xx is replaced by a hyphen "-"
              character, which indicates that they belong to this element, and
              that Diffserv code
                  point)</dd>
  <dt>UDP:</dt><dd>User Datagram Protocol)</dd>
  <dt>TCP:</dt><dd>Transport Control Protocol)</dd>
  <dt>QUIC:</dt><dd>QUIC transport protocol)</dd>
  <dt>HS:</dt><dd>Hand-Shake, such as TCP's 3-way HS)</dd>
  <dt>Poisson:</dt><dd>packet generation using Poisson
                  distribution)</dd>
  <dt>Periodic:</dt><dd>periodic packet generation)</dd>
  <dt>SendOnRcv:</dt><dd>sender keeps one packet in transit by sending
                  when previous packet arrives)</dd>
  <dt>PayloadxxxxB:</dt><dd>where xxxx is replaced by an integer, the
                  number of octets or 8-bit Bytes in the Payload)</dd>
  <dt>SustainedBurst:</dt><dd>capacity test, worst case)</dd>
  <dt>StandingQueue:</dt><dd>test of bottleneck queue behavior)</dd>
</dl>

</dd>
	      </dl>

              <t>SubTypeMethod values are separated by a hyphen "-"
              character, which indicates that they belong to this element and
              that their order is unimportant when considering name Name
              uniqueness.</t>

              <t>Spec: An

<ul empty="true">
<li>
          <dl newline="false" spacing="normal">
            <dt>Spec:</dt><dd>An immutable document identifier Identifier combined with a
              document section identifier. Identifier. For RFCs, this consists of the RFC
              number and major section number that specifies this Registry
              entry
              Rntry in the form RFCXXXXsecY, such as "RFCXXXXsecY", e.g., RFC7799sec3. Note: the The
              RFC number is not the Primary Reference primary reference specification for the
              metric definition, such as definition (e.g., <xref target="RFC7679"/> target="RFC7679"
              format="default"/> as the primary reference specification for One-way
              Delay;
              one-way delay metrics); it will contain the placeholder
              "RFCXXXXsecY" until the
              RFC number is assigned to the specifying document, document and would
              remain blank in private registry entries Private Registry Entries without a corresponding
              RFC. Anticipating the "RFC10K" problem, the number of the RFC
              continues to replace RFCXXXX "RFCXXXX", regardless of the number of digits
              in the RFC number. Anticipating Registry Entries from other
              standards bodies, the form of this Name Element MUST <bcp14>MUST</bcp14> be proposed
              and reviewed for consistency and uniqueness by the Expert
              Reviewer.</t>

              <t>Units: The
              Reviewer.</dd>

              <dt>Units:</dt><dd><t>The units of measurement for the output, such as and
              not limited to:<list style="empty">
                  <t>Seconds</t>

                  <t>Ratio (unitless)</t>

                  <t>Percent (value to:</t>

<!--</dd>
          </dl>
</li>
</ul> -->

<!--
<table anchor="units">
  <thead>
    <tr>
      <th>Name</th>
      <th>Description</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>Seconds</td>
      <td></td>
    </tr>
    <tr>
      <td>Ratio</td>
      <td>unitless</td>
    </tr>
    <tr>
      <td>Percent</td>
      <td>value multiplied by 100%)</t>

                  <t>Logical (1 or 0)</t>

                  <t>Packets</t>

                  <t>BPS (Bits 100%</td>
    </tr>
    <tr>
      <td>Logical</td>
      <td>1 or 0</td>
    </tr>
    <tr>
      <td>Packets</td>
      <td></td>
    </tr>
    <tr>
      <td>BPS</td>
      <td>bits per Second)</t>

                  <t>PPS (Packets second</td>
    </tr>
    <tr>
      <td>PPS</td>
      <td>packets per Second)</t>

                  <t>EventTotal (for unit-less counts)</t>

                  <t>Multiple (more second</td>
    </tr>
    <tr>
      <td>EventTotal</td>
      <td>for unitless counts</td>
    </tr>
    <tr>
      <td>Multiple</td>
      <td>more than one type of unit)</t>

                  <t>Enumerated (a unit</td>
    </tr>
    <tr>
      <td>Enumerated</td>
      <td>a list of outcomes)</t>

                  <t>Unitless</t>
                </list></t>

              <t>Output: The outcomes</td>
    </tr>
    <tr>
      <td>Unitless</td>
      <td></td>
    </tr>
  </tbody>
</table>
-->

<dl>
  <dt>Seconds</dt><dd/>
  <dt>Ratio:</dt><dd>unitless</dd>
  <dt>Percent:</dt><dd>value multiplied by 100%</dd>
  <dt>Logical:</dt><dd>1 or 0</dd>
  <dt>Packets</dt><dd/>
  <dt>BPS:</dt><dd>bits per second</dd>
  <dt>PPS:</dt><dd>packets per second</dd>
  <dt>EventTotal:</dt><dd>for unitless counts</dd>
  <dt>Multiple:</dt><dd>more than one type of unit</dd>
  <dt>Enumerated:</dt><dd>a list of outcomes</dd>
  <dt>Unitless</dt><dd/>
              </dl>
	  </dd>
          </dl>

            <dl newline="false" spacing="normal">
              <dt>Output:</dt><dd><t>The type of output resulting from measurement, such
              as and not limited to:<list style="empty">
                  <t>Singleton</t>

                  <t>Raw to:</t>

<!--</dd>
            </dl>-->

<!--
<table anchor="output">
  <thead>
    <tr>
      <th>Name</th>
      <th>Description</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>Singleton</td>
      <td></td>
    </tr>
    <tr>
      <td>Raw</td>
      <td>multiple singletons</td>
    </tr>
    <tr>
      <td>Count</td>
      <td></td>
    </tr>
    <tr>
      <td>Minimum</td>
      <td></td>
    </tr>
    <tr>
      <td>Maximum</td>
      <td></td>
    </tr>
    <tr>
      <td>Median</td>
      <td></td>
    </tr>
    <tr>
      <td>Mean</td>
      <td></td>
    </tr>
    <tr>
      <td>95Percentile</td>
      <td>95th percentile</td>
    </tr>
    <tr>
      <td>99Percentile</td>
      <td>99th percentile</td>
    </tr>
    <tr>
      <td>StdDev</td>
      <td>standard deviation</td>
    </tr>
    <tr>
      <td>Variance</td>
      <td></td>
    </tr>
    <tr>
      <td>PFI</td>
      <td>pass, fail, inconclusive</td>
    </tr>
    <tr>
      <td>FlowRecords</td>
      <td>descriptions of flows observed</td>
    </tr>
    <tr>
      <td>LossRatio</td>
      <td>lost packets to total packets, &lt;=1</td>
    </tr>
  </tbody>
</table>
-->
<dl>
  <dt>Singleton</dt><dd/>
  <dt>Raw:</dt><dd>multiple singletons</dd>
  <dt>Count</dt><dd/>
  <dt>Minimum</dt><dd/>
  <dt>Maximum</dt><dd/>
  <dt>Median</dt><dd/>
  <dt>Mean</dt><dd/>
  <dt>95Percentile:</dt><dd>95th percentile</dd>
  <dt>99Percentile:</dt><dd>99th percentile</dd>
  <dt>StdDev:</dt><dd>standard deviation</dd>
  <dt>Variance</dt><dd/>
  <dt>PFI:</dt><dd>pass, fail, inconclusive</dd>
  <dt>FlowRecords:</dt><dd>descriptions of flows observed</dd>
  <dt>LossRatio:</dt><dd>lost packets to total packets, &lt;=1</dd>
	    </dl>
	  </dd>
	</dl>
</li>
</ul>
      </dd>
    </dl>

<!--
              <ul empty="true" spacing="normal">
                <li>Singleton</li>
                <li>Raw (multiple Singletons)</t>

                  <t>Count</t>

                  <t>Minimum</t>

                  <t>Maximum</t>

                  <t>Median</t>

                  <t>Mean</t>

                  <t>95Percentile singletons)</li>
                <li>Count</li>
                <li>Minimum</li>
                <li>Maximum</li>
                <li>Median</li>
                <li>Mean</li>
                <li>95Percentile (95th Percentile)</t>

                  <t>99Percentile percentile)</li>
                <li>99Percentile (99th Percentile)</t>

                  <t>StdDev (Standard Deviation)</t>

                  <t>Variance</t>

                  <t>PFI (Pass, Fail, Inconclusive)</t>

                  <t>FlowRecords percentile)</li>
                <li>StdDev (standard deviation)</li>
                <li>Variance</li>
                <li>PFI (pass, fail, inconclusive)</li>
                <li>FlowRecords (descriptions of flows observed)</t>

                  <t>LossRatio observed)</li>
                <li>LossRatio (lost packets to total packets, &lt;=1)</t>
                </list></t>
            </list>An example is:</t>

          <t>RTDelay_Active_IP-UDP-Periodic_RFCXXXXsecY_Seconds_95Percentile</t>

          <t>as &lt;=1)</li>
              </ul>
-->
          <t>An example, as described in section 4 of <xref
          target="I-D.ietf-ippm-initial-registry"/>.</t> target="RFC8912"
          sectionFormat="of" section="4"/>, is</t>

         <ul empty="true" spacing="normal">
          <li>RTDelay_Active_IP-UDP-Periodic_RFC8912sec4_Seconds_95Percentile</li>
         </ul>

          <t>Note that private registries following the format described here
          SHOULD
          <bcp14>SHOULD</bcp14> use the prefix "Priv_" on any name Name to avoid unintended
          conflicts (further considerations are described in section 10). <xref target="iana-cons"/>).
          Private registry entries Registry Entries usually have no specifying RFC, thus RFC; thus, the
          Spec: element has no clear interpretation.</t>
        </section>

        <section title="URI"> numbered="true" toc="default">
          <name>URI</name>

          <t>The URIs URI column MUST <bcp14>MUST</bcp14> contain a URL <xref target="RFC3986"/> target="RFC3986" format="default"/> that
          uniquely identifies and locates the metric entry Metric Entry so it is accessible
          through the Internet. The URL points to a file containing all of the
          human-readable information for one registry entry. Registry Entry. The URL SHALL <bcp14>SHALL</bcp14>
          reference a target file that is preferably HTML-formatted and
          contains URLs to referenced sections of HTML-ized HTMLized RFCs, or other
          reference specifications. These target files for different entries
          can be more easily edited and re-used reused when preparing new entries.
          The exact form of the URL for each target file, and the target file
          itself, will be determined by IANA and reside on "iana.org". The
          <eref target="https://www.iana.org/" brackets="angle"/>.
          <xref target="RFC8912" sectionFormat="of" section="4"/>, as well as
          subsequent major sections of <xref target="I-D.ietf-ippm-initial-registry"/> that document, provide an example of a target file in HTML form (sections 4 and
          higher).</t> form.</t>
        </section>
        <section title="Description"> numbered="true" toc="default">
          <name>Description</name>
          <t>A Registered Performance Metric description is a written
          representation of a particular Performance Metrics Registry entry. Entry.
          It supplements the Registered Performance Metric name Name to help
          Performance Metrics Registry users select relevant Registered
          Performance Metrics.</t>
        </section>
        <section title="Reference">
          <t>This numbered="true" toc="default">
          <name>Reference</name>
<!-- Would "proposed" a better word choice than "candidate"?  Note that
"candidate" is used throughout; we would apply this update globally.

Examples:

Original:
   This entry gives the specification containing the candidate registry
   entry which was reviewed and agreed, if such an RFC or other
   specification exists.

Original:
   In essence, there needs to be evidence that a candidate Registered
   Performance Metric has significant industry interest, or has seen
   deployment, and there is agreement that the candidate Registered
   Performance Metric serves its intended purpose.

-->
          <t>This entry gives the specification containing the candidate
          Registry Entry that was reviewed and agreed upon, if such an RFC or
          other specification exists.</t>
        </section>
        <section title="Change Controller"> numbered="true" toc="default">
          <name>Change Controller</name>
          <t>This entry names the entity responsible for approving revisions
          to the registry entry, Registry Entry and SHALL <bcp14>SHALL</bcp14> provide contact information (for an
          individual, where appropriate).</t>
        </section>
        <section title="Version numbered="true" toc="default">
          <name>Version (of Registry Format)"> Format)</name>
          <t>This entry gives the version number for the registry Registry format used.
          Formats complying with this memo MUST <bcp14>MUST</bcp14> use 1.0. The version number
          SHALL NOT
          <bcp14>SHALL NOT</bcp14> change unless a new RFC is published that changes the
          registry
          Registry format. The version number of registry entries SHALL NOT Registry Entries <bcp14>SHALL NOT</bcp14>
          change unless the registry entry Registry Entry is updated (following the procedures in
          section 8).</t>
          <xref target="managing-perf-metric-grp"/>).</t>
        </section>

        <!--      <section title="Reference Specification(s)">
        <t>Registered Performance Metrics that follow the common columns must provide the
        reference specification(s) on which the Registered Performance Metric
        is based.</t>
      </section>-->
      </section>

      <section title="Metric numbered="true" toc="default">

        <name>Metric Definition Category"> Category</name>
        <t>This category includes columns to prompt all necessary details
        related to the metric definition, including the immutable document
        reference and values of input factors, called fixed parameters, "Fixed Parameters", which
        are left open in the immutable document, document but have a particular value
        defined by the performance metric.</t> Performance Metric.</t>
        <section title="Reference Definition"> numbered="true" toc="default">
          <name>Reference Definition</name>
          <t>This entry provides a reference (or references) to the relevant
          section(s)
          sections of the document(s) document or documents that define the metric, as well as any
          supplemental information needed to ensure an unambiguous definition
          for implementations. The A given reference needs to be an immutable
          document, such as an RFC; for other standards bodies, it is likely
          to be necessary to reference a specific, dated version of a
          specification.</t>
        </section>
        <section title="Fixed Parameters"> numbered="true" toc="default">
          <name>Fixed Parameters</name>
          <t>Fixed Parameters are Parameters whose value values must be specified in
          the Performance Metrics Registry. The measurement system uses these
          values.</t>
          <t>Where referenced metrics supply a list of Parameters as part of
          their descriptive template, a sub-set subset of the Parameters will be
          designated as Fixed Parameters. As an example for active metrics, Active Metrics,
          Fixed Parameters determine most or all of the IPPM Framework framework
          convention "packets of Type-P" as described in <xref
          target="RFC2330"/>,
          target="RFC2330" format="default"/>, such as transport protocol,
          payload length, TTL, etc. An example for passive metrics Passive Metrics is for an RTP packet loss
          calculation that relies on the validation of a packet as RTP RTP, which
          is a multi-packet validation controlled by the MIN_SEQUENTIAL variable as defined
          by <xref target="RFC3550"/>. target="RFC3550" format="default"/>. Varying MIN_SEQUENTIAL values can alter
          the loss report report, and this value variable could be set as a Fixed
          Parameter.</t>
          <t>Parameters MUST <bcp14>MUST</bcp14> have well-defined names. Names. For human readers, the
          hanging indent
          hanging-indent style is preferred, and any Parameter names Names and
          definitions that do not appear in the Reference Method Specification
          MUST
          <bcp14>MUST</bcp14> appear in this column (or Run-time the Runtime Parameters column).</t>
          <t>Parameters MUST <bcp14>MUST</bcp14> have a well-specified data format.</t>
          <t>A Parameter which that is a Fixed Parameter for one Performance
          Metrics Registry entry Entry may be designated as a Run-time Runtime Parameter for
          another Performance Metrics Registry entry.</t> Entry.</t>
        </section>
      </section>
      <section title="Method numbered="true" toc="default">
        <name>Method of Measurement Category"> Category</name>
        <t>This category includes columns for references to relevant sections
        of the immutable document(s) and any supplemental information needed
        to ensure an unambiguous method for implementations.</t>
        <section title="Reference Method"> numbered="true" toc="default">
          <name>Reference Method</name>
          <t>This entry provides references to relevant sections of immutable
          documents, such as RFC(s) (for other standards bodies, it is likely
          to be necessary to reference a specific, dated version of a
          specification) describing the method Method of measurement, Measurement, as well as any
          supplemental information needed to ensure unambiguous interpretation
          for implementations referring to the immutable document text.</t>
          <t>Specifically, this section should include pointers to pseudocode
          or actual code that could be used for an unambiguous
          implementation.</t>
        </section>
        <section title="Packet numbered="true" toc="default">
          <name>Packet Stream Generation"> Generation</name>
          <t>This column applies to Performance Metrics that generate traffic
          as part of their Measurement Method, including including, but not necessarily
          limited to to, Active metrics. Metrics. The generated traffic is referred to as a
          stream
          "stream", and this column describes its characteristics.</t>

          <!--          <t>Some metrics, such as those intended for passive monitoring or
        RTCP and RTCP-XR metrics, will not specify an entry for this
        column.</t> -->
          <t>Each entry for this column contains the following information:
          <list style="symbols">
              <t>Value: The
          </t>
      <dl newline="false" spacing="normal">
            <dt>Value:</dt><dd>The name of the packet stream scheduling
              discipline</t>

              <t>Reference: the
              discipline</dd>
            <dt>Reference:</dt><dd>The specification where the parameters Parameters of the
              stream are defined</t>
            </list></t> defined</dd>
      </dl>
          <t>The packet generation stream may require parameters Parameters such as the
          average packet rate and distribution truncation value for streams
          with Poisson-distributed inter-packet sending times. In case If such
          parameters
          Parameters are needed, they should be included either in either the Fixed
          parameter
          Parameters column or in the run time parameter Runtime Parameters column, depending on
          whether they will be fixed or will be an input for the metric.</t>
          <t>The simplest example of stream specification is Singleton singleton
          scheduling (see <xref target="RFC2330"/>), target="RFC2330" format="default"/>), where a single atomic
          measurement is conducted. Each atomic measurement could consist of
          sending a single packet (such as a DNS request) or sending several
          packets (for example, to request a webpage). web page). Other streams support a
          series of atomic measurements in a "sample", with a schedule
          defining the timing between each transmitted packet and subsequent
          measurement. Principally, two different streams are used in IPPM
          metrics, Poisson
          Metrics: (1)&nbsp;Poisson, distributed as described in <xref
          target="RFC2330"/> target="RFC2330" format="default"/> and Periodic (2)&nbsp;periodic, as described in <xref
          target="RFC3432"/>. target="RFC3432" format="default"/>. Both Poisson and Periodic periodic have their own unique
          parameters,
          Parameters, and the relevant set of parameters names Parameter Names and values
          should be included either in either the Fixed Parameters column or in the
          Run-time parameter
          Runtime Parameters column.</t>
        </section>
        <section title="Traffic Filter"> numbered="true" toc="default">
          <name>Traffic Filter</name>
          <t>This column applies to Performance Metrics that observe packets
          flowing through (the device with) the measurement agent i.e. Measurement Agent, i.e.,
          packets that is are not necessarily addressed to the measurement agent. Measurement Agent.
          This includes includes, but is not limited to to, Passive Metrics. The filter
          specifies the traffic that is measured. This includes protocol field
          values/ranges, such as address ranges, and flow or session
          identifiers.</t>
          Identifiers.</t>
          <t>The traffic filter Traffic Filter itself depends on the needs of the metric itself
          and a balance of an operator's measurement needs and a user's need
          for privacy. Mechanics for conveying the filter criteria might be
          the BPF (Berkley (Berkeley Packet Filter) or PSAMP (Packet Sampling) <xref target="RFC5475"/> target="RFC5475" format="default"/>
          Property Match Filtering Filtering, which reuses IPFIX <xref
          target="RFC7012"/>. target="RFC7012" format="default"/>. An example BPF string for matching TCP/80
          traffic to remote destination Destination net 192.0.2.0/24 would be "dst net
          192.0.2.0/24 and tcp dst port 80". More complex filter Filter engines that are more complex might
          be supported by the implementation that might allow for matching
          using Deep Packet Inspection (DPI) technology.</t>
          <t>The traffic filter Traffic Filter includes the following information: <list>
              <t>Type: the </t>
      <dl newline="false" spacing="normal">
            <dt>Type:</dt><dd>The type of traffic filter Traffic Filter used, e.g. e.g., BPF, PSAMP,
              OpenFlow rule, etc. etc., as defined by a normative reference</t>

              <t>Value: the reference</dd>
            <dt>Value:</dt><dd>The actual set of rules expressed</t>
            </list></t> expressed</dd>
      </dl>
        </section>
        <section title="Sampling Distribution">
          <t><!--This sentence seems awkward to me.-->The numbered="true" toc="default">
          <name>Sampling Distribution</name>
          <t>The sampling distribution defines defines, out of all of the packets that
          match the traffic
          filter, Traffic Filter, which one or more of those packets are
          actually used for the measurement.  One possibility is "all" "all", which
          implies that all packets matching the Traffic filter Filter are considered,
          but there may be other sampling strategies. It includes the following information: <list>
              <t>Value: the </t>
        <dl newline="false" spacing="normal">
            <dt>Value:</dt><dd>The name of the sampling distribution</t>

              <t>Reference definition: pointer distribution</dd>
            <dt>Reference definition:</dt><dd>Pointer to the specification where the
              sampling distribution is properly defined.</t>
            </list></t> defined</dd>
        </dl>
          <t>The sampling distribution may require parameters. In case Parameters. If such
          parameters
          Parameters are needed, they should be included either in either the Fixed
          parameter
          Parameters column or in the run time parameter Runtime Parameters column, depending on
          whether they will be fixed or will be an input for the metric.</t>

          <t>Sampling
          <t>PSAMP is documented in "Sampling and Filtering Techniques for IP Packet Selection are
          documented in the PSAMP (Packet Sampling) Selection" <xref target="RFC5475"/>, target="RFC5475" format="default"/>,
          while the "A Framework for Packet Selection and Reporting, Reporting" <xref
          target="RFC5474"/> target="RFC5474" format="default"/> provides more background information. The
          sampling distribution parameters Parameters might be expressed in terms of
          the
          Information model described in "Information Model for Packet Sampling Exports,
          Exports" <xref
          target="RFC5477"/>, target="RFC5477" format="default"/> and the Flow process
          provided in "Flow Selection Techniques, Techniques" <xref
          target="RFC7014"/>.</t> target="RFC7014" format="default"/>.</t>
        </section>
        <section title="Run-time Parameters">
          <t>Run-Time numbered="true" toc="default">
          <name>Runtime Parameters</name>
          <t>Runtime Parameters are Parameters that must be determined,
          configured into the measurement system, and reported with the
          results for the context to be complete. However, the values of these
          parameters is
          Parameters are not specified in the Performance Metrics Registry
          (like the Fixed Parameters), rather Parameters); rather, these parameters Parameters are listed as
          an aid to the measurement system implementer or user (they must be
          left as variables, and supplied on execution).</t>
          <t>Where metrics supply a list of Parameters as part of their
          descriptive template, a sub-set subset of the Parameters will be designated
          as Run-Time Runtime Parameters.</t>
          <t>Parameters MUST <bcp14>MUST</bcp14> have well defined names. well-defined Names. For human readers, the
          hanging indent
          hanging-indent style is preferred, and the names Names and definitions
          that do not appear in the Reference Method Specification MUST <bcp14>MUST</bcp14> appear
          in this column.</t>
          <t>A Data Format data format for each Run-time Runtime Parameter MUST <bcp14>MUST</bcp14> be specified in
          this column, to simplify the control and implementation of
          measurement devices. For example, parameters Parameters that include an IPv4
          address can be encoded as a 32 bit 32-bit integer (i.e. (i.e., a binary base64
          encoded
          base64-encoded value) or ip-address "ip&nbhy;address" as defined in <xref target="RFC6991"/>. target="RFC6991" format="default"/>.
          The actual encoding(s) used must be explicitly defined for each
          Run-time parameter.
          Runtime Parameter. IPv6 addresses and options MUST <bcp14>MUST</bcp14> be accommodated,
          allowing Registered Performance Metrics to be used in that address family. Other
          address families are permissable.</t> permissible.</t>
          <t>Examples of Run-time Runtime Parameters include IP addresses, measurement
          point designations, start times and end times for measurement, and
          other information essential to the method Method of measurement.</t> Measurement.</t>
        </section>
        <section title="Role"> numbered="true" toc="default">
          <name>Role</name>
          <t>In some methods Methods of measurement, Measurement, there may be several roles
          defined, e.g., for a one-way packet delay active measurement Active Measurement, there
          is one measurement agent Measurement Agent that generates the packets and another
          agent
          Agent that receives the packets. This column contains the name of
          the Role(s) for this particular entry. In the one-way delay example
          above, there should be two entries in the Registry's Role registry column, one
          for each Role (Source and Destination). When a measurement agent Measurement Agent is
          instructed to perform the "Source" Role for the one-way delay metric,
          the agent Agent knows that it is required to generate packets. The values
          for this field are defined in the reference method Reference Method of measurement Measurement
          (and this frequently results in abbreviated role names such as
          "Src").</t>
          <t>When the Role column of a registry entry defines Registry Entry defines more than one
          Role, then the Role SHALL <bcp14>SHALL</bcp14> be treated as a Run-time Runtime Parameter and
          supplied for execution. It should be noted that the LMAP framework
          <xref target="RFC7594"/> target="RFC7594" format="default"/> distinguishes the Role from other Run-time
          Parameters, and defines a special parameter "Roles" inside the
          registry-grouping function list in the LMAP YANG model<xref
          target="RFC8194"/>.</t> Runtime
          Parameters.</t>
        </section>
      </section>
      <section title="Output Category"> numbered="true" toc="default">
        <name>Output Category</name>
        <t>For entries which that involve a stream and many singleton measurements,
        a statistic may be specified in this column to summarize the results
        to a single value. If the complete set of measured singletons is
        output, this will be specified here.</t>
        <t>Some metrics embed one specific statistic in the reference metric
        definition, while others allow several output types or statistics.</t>
        <section title="Type"> numbered="true" toc="default">
          <name>Type</name>
          <t>This column contains the name of the output type. The output type
          defines a single type of result that the metric produces. It can be
          the raw results (packet send times and singleton metrics), or it can
          be a summary statistic. The specification of the output type MUST <bcp14>MUST</bcp14>
          define the format of the output. In some systems, format
          specifications will simplify both measurement implementation and
          collection/storage tasks. Note that if two different statistics are
          required from a single measurement (for example, both "Xth
          percentile mean" and "Raw"), then a new output type must be defined
          ("Xth percentile mean AND Raw"). See the Naming section <xref target="name-sec7-1-2"/>
          above for a list of Output Types.</t>
        </section>

        <!--
        <section title="Data Format">
			<t>This column provides the data format for the output. It is provided to simplify the communication with
           collection systems and implementation of measurement
           devices.</t> output types.</t>
        </section>
-->
        <section title="Reference Definition"> numbered="true" toc="default">
          <name>Reference Definition</name>
          <t>This column contains a pointer to the specification(s) where the
          output type and format are defined.</t>
        </section>
        <section title="Metric Units"> numbered="true" toc="default">
          <name>Metric Units</name>
          <t>The measured results must be expressed using some standard
          dimension or units of measure. This column provides the units.</t>
          <t>When a sample of singletons (see Section 11 of<xref
          target="RFC2330"/> <xref target="RFC2330"
          sectionFormat="of" section="11"/> for definitions of these terms) is collected,
          this entry will specify the units for each measured value.</t>
        </section>
        <section title="Calibration"> numbered="true" toc="default">
          <name>Calibration</name>
          <t>Some specifications for Methods of Measurement include the
          possibility
          ability to perform an error calibration. Section 3.7.3 of <xref
          target="RFC7679"/> target="RFC7679" sectionFormat="of" section="3.7.3"/> is one example. In the registry entry, Registry Entry, this field
          will identify a method of calibration for the metric, and and, when
          available, the measurement system SHOULD <bcp14>SHOULD</bcp14> perform the calibration
          when requested and produce the output with an indication that it is
          the result of a calibration method. In-situ In situ calibration could be
          enabled with an internal loopback that includes as much of the
          measurement system as possible, performs address manipulation as
          needed, and provides some form of isolation (e.g., deterministic
          delay) to avoid send-receive interface contention. Some portion of
          the random and systematic error can be characterized in this way.</t>
          <t>For one-way delay measurements, the error calibration must
          include an assessment of the internal clock synchronization with its
          external reference (this internal clock is supplying timestamps for
          measurement). In practice, the time offsets of clocks at both the
          source
          Source and destination Destination are needed to estimate the systematic error
          due to imperfect clock synchronization (the time offsets are
          smoothed, thus
          smoothed; thus, the random variation is not usually represented in
          the results).</t>
          <t>Both internal loopback calibration and clock synchronization can
          be used to estimate the *available accuracy* of the Output Metric
          Units. For example, repeated loopback delay measurements will reveal
          the portion of the Output output result resolution which that is the result of
          system noise, noise and is thus inaccurate.</t>
        </section>
      </section>
      <section title="Administrative information">
        <section title="Status">
          <t>The numbered="true" toc="default">
        <name>Administrative Information</name>
        <section numbered="true" toc="default">
          <name>Status</name>
          <t>This entry indicates the status of the specification of this Registered Performance
          Metric. Allowed values are 'current' 'Current' and 'deprecated'. 'Deprecated'. All newly
          defined Information Elements have 'current' 'Current' status.</t>
        </section>
        <section title="Requester">
          <t>The numbered="true" toc="default">
          <name>Requester</name>
          <t>This entry indicates the requester for the Registered Performance Metric. The
          requester MAY <bcp14>MAY</bcp14> be a document, such document (such as RFC, an RFC) or a person.</t>
        </section>
        <section title="Revision">
          <t>The numbered="true" toc="default">
          <name>Revision</name>
          <t>This entry indicates the revision number of a Registered Performance Metric, starting
          at 0 for Registered Performance Metrics at the time of definition and
          incremented by one for each revision.</t>
        </section>
        <section title="Revision Date">
          <t>The numbered="true" toc="default">
          <name>Revision Date</name>
          <t>This entry indicates the date of acceptance or of the most recent revision for the
          Registered Performance Metric. The date SHALL <bcp14>SHALL</bcp14> be determined by IANA
          and the reviewing Performance Metrics Expert.</t>
        </section>
      </section>
      <section title="Comments numbered="true" toc="default">
        <name>Comments and Remarks"> Remarks</name>
        <t>Besides providing additional details which that do not appear in other
        categories, this open Category category (single column) allows for unforeseen
        issues to be addressed by simply updating this informational
        entry.</t>
      </section>
    </section>
    <section title="Processes anchor="managing-perf-metric-grp" numbered="true" toc="default">
      <name>Processes for Managing the Performance Metric Metrics Registry Group"> Group</name>
      <t>Once a Performance Metric or set of Performance Metrics has been
      identified for a given application, candidate Performance Metrics
      Registry entry Entry specifications prepared in accordance with <xref
      target="columns"/> target="columns" format="default"/> should be submitted to IANA to follow the process for
      review by the Performance Metric Metrics Experts, as defined below. This process
      is also used for other changes to the Performance Metrics Registry, such
      as deprecation or revision, as described later in this section.</t>
      <t>It is desirable that the author(s) of a candidate Performance Metrics
      Registry entry Entry seek review in the relevant IETF working group, group or offer
      the opportunity for review on the working group mailing list.</t>
      <section title="Adding new anchor="add-new-perf-metrics" numbered="true" toc="default">
        <name>Adding New Performance Metrics to the Performance Metrics Registry"> Registry</name>
        <t>Requests to add Registered Performance Metrics in the Performance
        Metrics Registry SHALL <bcp14>SHALL</bcp14> be submitted to IANA, which forwards the
        request to a designated group of experts (Performance Metric Metrics Experts)
        appointed by the IESG; these are the reviewers called for by the
        Specification Required <xref target="RFC8126"/> policy <xref target="RFC8126" format="default"/> defined for the
        Performance Metrics Registry. The Performance Metric Metrics Experts review
        the request for such things as compliance with this document,
        compliance with other applicable Performance Metric-related Metrics-related RFCs, and
        consistency with the currently defined set of Registered Performance
        Metrics. The most efficient path for submission begins with
        preparation of an Internet Draft Internet-Draft containing the proposed Performance
        Metrics Registry entry Entry using the template in Section 11, <xref target="blank-reg-template"/>, so that the
        submission formatting will benefit from the normal IETF Internet Draft Internet-Draft
        submission processing (including HTML-ization).</t> HTMLization).</t>
        <t>Submission to IANA may be during IESG review (leading to IETF
        Standards Action), where an Internet Draft Internet-Draft proposes one or more
        Registered Performance Metrics to be added to the Performance Metrics
        Registry, including the text of the proposed Registered Performance
        Metric(s).</t>
        Metric&wj;(s).</t>
        <t>If an RFC-to-be includes a Performance Metric and a proposed
        Performance Metrics Registry entry, Entry but the Performance Metric Expert Metrics Expert's
        review determines that one or more of the Section 5 criteria listed in <xref target="metrics-criteria"/> have not
        been met, then the proposed Performance Metrics Registry entry MUST Entry <bcp14>MUST</bcp14> be
        removed from the text. Once evidence exists that the Performance
        Metric meets the criteria in section 5, <xref target="metrics-criteria"/>, the proposed Performance
        Metrics Registry entry SHOULD Entry <bcp14>SHOULD</bcp14> be submitted to IANA to be evaluated in
        consultation with the Performance Metric Metrics Experts for registration at
        that time.</t>
        <t>Authors of proposed Registered Performance Metrics SHOULD <bcp14>SHOULD</bcp14> review
        compliance with the specifications in this document to check their
        submissions before sending them to IANA.</t>
        <t>At least one Performance Metric Metrics Expert should endeavor to complete
        referred reviews in a timely manner. If the request is acceptable, the
        Performance Metric Metrics Experts signify their approval to IANA, and IANA
        updates the Performance Metrics Registry. If the request is not
        acceptable, the Performance Metric Metrics Experts MAY <bcp14>MAY</bcp14> coordinate with the
        requester to change the request to be compliant, otherwise so that it is compliant; otherwise, IANA SHALL <bcp14>SHALL</bcp14>
        coordinate resolution of issues on behalf of the expert. The
        Performance Metric Metrics Experts MAY <bcp14>MAY</bcp14> choose to reject clearly frivolous or
        inappropriate change requests outright, but such exceptional
        circumstances should be rare.</t>
        <t>This process should not in any way be construed as allowing the
        Performance Metric Metrics Experts to overrule IETF consensus. Specifically,
        any Registered Performance Metrics that were added to the Performance
        Metrics Registry with IETF consensus require IETF consensus for
        revision or deprecation.</t>
        <t>Decisions by the Performance Metric Metrics Experts may be appealed as in
        Section 7 of per
        <xref target="RFC8126"/>.</t> target="RFC8126" sectionFormat="of" section="10"/>.</t>
      </section>
      <section title="Revising Registered Performance Metrics">
        <!--        <t>Requests to revise the Performance Metrics Registry or a linked
        sub-registry are submitted to IANA, which forwards the request to a
        designated group of experts (Performance Metric Experts) appointed by
        the IESG; these are the reviewers called for by the Expert Review
        [RFC5226] policy defined for the Performance Metrics Registry. The
        Performance Metric Experts review the request for such things as
        compliance with this document, compliance with other applicable
        Performance Metric-related RFCs, and consistency with the currently
        defined set of anchor="revise-reg-perf-metrics" numbered="true" toc="default">
        <name>Revising Registered Performance Metrics.</t>
--> Metrics</name>
        <t>A request for Revision revision is only permitted when the requested changes
        maintain backward-compatibility backward compatibility with implementations of the prior
        Performance Metrics Registry entry Entry describing a Registered Performance
        Metric (entries with lower revision numbers, numbers but having the same Identifier
        and Name).</t>
        <t>The purpose of the Status field in the Performance Metrics Registry
        is to indicate whether the entry for a Registered Performance Metric
        is 'current' 'Current' or 'deprecated'.</t> 'Deprecated'.</t>
        <t>In addition, no policy is defined for revising the Performance
        Metric entries Entries in the IANA Registry registry or addressing errors therein. To
        be clear, changes and deprecations within the Performance Metrics
        Registry are not encouraged, encouraged and should be avoided to the extent
        possible. However, in recognition that change is inevitable, the
        provisions of this section address the need for revisions.</t>
        <t>Revisions are initiated by sending a candidate Registered
        Performance Metric definition to IANA, as in Section 8.1, per <xref target="add-new-perf-metrics"/>, identifying
        the existing Performance Metrics Registry entry, Entry, and explaining how
        and why the existing entry should be revised.</t>
        <t>The primary requirement in the definition of procedures for
        managing changes to existing Registered Performance Metrics is
        avoidance of measurement interoperability problems; the Performance
        Metric
        Metrics Experts must work to maintain interoperability above all else.
        Changes to Registered Performance Metrics may only be done in an
        interoperable way; necessary changes that cannot be done in a way to
        allow that
        allows interoperability with unchanged implementations MUST <bcp14>MUST</bcp14> result in
        the creation of a new Registered Performance Metric (with a new Name,
        replacing the RFCXXXXsecY portion of the name) Name) and possibly the
        deprecation of the earlier metric.</t>
        <t>A change to a Registered Performance Metric SHALL <bcp14>SHALL</bcp14> be determined to
        be backward-compatible backward compatible when: <list style="numbers">
            <t>it </t>
        <ol spacing="normal" type="1">
          <li>it involves the correction of an error that is obviously only
            editorial; or</t>

            <t>it
            editorial, or</li>
          <li>it corrects an ambiguity in the Registered Performance Metric's
            definition, which itself leads to issues severe enough to prevent
            the Registered Performance Metric's usage as originally defined;
            or</t>

            <t>it defined,
            or</li>
          <li>it corrects missing information in the metric definition
            without changing its meaning (e.g., the explicit definition of
            'quantity' semantics for numeric fields without a Data Type
            Semantics value); or</t>

            <t>it value), or</li>
          <li>it harmonizes with an external reference that was itself
            corrected.</t>

            <!--            <t>"BENOIT: NOTE THAT THERE ARE MORE RULES IN RFC 7013 SECTION 5
            BUT THEY WOULD ONLY APPLY TO THE ACTIVE/PASSIVE DRAFTS. TO BE
            DISCUSSED."</t> -->
          </list></t>
            corrected.</li>
          </ol>
        <t>If a Performance Metric revision is deemed permissible and
        backward-compatible
        backward compatible by the Performance Metric Metrics Experts, according to
        the rules in this document, IANA SHOULD <bcp14>SHOULD</bcp14> execute the change(s) in the
        Performance Metrics Registry. The requester of the change is appended
        to the original requester in the Performance Metrics Registry. The
        Name of the revised Registered Performance Metric, including the
        RFCXXXXsecY portion of the name, SHALL Name, <bcp14>SHALL</bcp14> remain unchanged (even even when the
        change is the result of IETF Standards Action; the Action. The revised registry
        entry SHOULD Registry
        Entry <bcp14>SHOULD</bcp14> reference the new immutable document, such as an RFC or
        for RFC. For other standards bodies, it is likely to be necessary to reference
        a specific, dated version of a specification, in an appropriate
        category and column).</t> column.</t>
        <t>Each Registered Performance Metric in the Performance Metrics
        Registry has a revision number, starting at zero. Each change to a
        Registered Performance Metric following this process increments the
        revision number by one.</t>
        <t>When a revised Registered Performance Metric is accepted into the
        Performance Metrics Registry, the date of acceptance of the most
        recent revision is placed into the revision Revision Date column of the
        registry
        Registry for that Registered Performance Metric.</t>
        <t>Where applicable, additions to Registered Performance Metrics in
        the form of text in the Comments or Remarks column should include the date, but such
        additions may not constitute a revision according to this process.</t>
        <t>Older version(s) versions of the updated metric entries Metric Entries are kept in the
        registry
        Registry for archival purposes. The older entries are kept with all
        fields unmodified (version, revision date) (Version, Revision Date) except for the status field
        that SHALL Status field,
        which <bcp14>SHALL</bcp14> be changed to "Deprecated".</t> 'Deprecated'.</t>
      </section>
      <section title="Deprecating numbered="true" toc="default">
        <name>Deprecating Registered Performance Metrics"> Metrics</name>
        <t>Changes that are not permissible by the above criteria for a
        Registered Performance Metric's revision may only be handled by
        deprecation. A Registered Performance Metric MAY <bcp14>MAY</bcp14> be deprecated and
        replaced when: <list style="numbers">
            <t>the </t>
        <ol spacing="normal" type="1">
          <li>the Registered Performance Metric definition has an error or
            shortcoming that cannot be permissibly changed as in Section 8.2
            Revising per <xref target="revise-reg-perf-metrics"/>
            ("Revising Registered Performance Metrics; or</t>

            <t>the Metrics"), or</li>
          <li>the deprecation harmonizes with an external reference that was
            itself deprecated through that reference's accepted deprecation
            method.</t>
          </list></t>
            method.</li>
        </ol>
        <t>A request for deprecation is sent to IANA, which passes it to the
        Performance Metric Metrics Experts for review. When deprecating an a Performance
        Metric, the Performance Metric description in the Performance Metrics
        Registry must be updated to explain the deprecation, as well as to
        refer to any new Performance Metrics created to replace the deprecated
        Performance Metric.</t>
        <t>The revision number of a Registered Performance Metric is
        incremented upon deprecation, and the revision Revision Date is updated, as with
        any revision.</t>
        <t>The intentional use of deprecated Registered Performance Metrics
        should result in a log entry or human-readable warning by the
        respective application.</t>
        <t>Names and Metric IDs of deprecated Registered Performance Metrics
        must not be reused.</t>
        <t>The deprecated entries are kept with all fields unmodified, except
        the version, revision date, Version field, the Revision Date field, and the status Status field (changed
        (which is changed to
        "Deprecated").</t> 'Deprecated').</t>
      </section>
    </section>

    <!--    <section title="Performance Metrics Registry and other Registries">
      <t>BENOIT: TBD.</t>

      <t>THE BASIC IDEA IS THAT PEOPLE COULD DIRECTLY DEFINE PERF. METRICS IN
      OTHER EXISTING REGISTRIES, FOR SPECIFIC PROTOCOL/ENCODING. EXAMPLE:
      IPFIX. IDEALLY, ALL PERF. METRICS SHOULD BE DEFINED IN THIS REGISTRY AND
      REFERS TO FROM OTHER REGISTRIES.</t>
    </section>
-->
    <section title="Security considerations"> numbered="true" toc="default">
      <name>Security Considerations</name>
      <t>This draft document defines a registry structure, Registry structure and does not itself
      introduce any new security considerations for the Internet. The
      definition of Performance Metrics for this registry Registry may introduce some
      security concerns, but the mandatory references should have their own
      considerations for security, and such definitions should be reviewed
      with security in mind if the security considerations are not covered by
      one or more reference standards.</t>
      <t>The aggregated results of the performance metrics Performance Metrics described in this
      registry
      Registry might reveal network topology information that may be
      considered sensitive. If such cases are found, then access control
      mechanisms should be applied.</t>
    </section>
    <section title="IANA Considerations"> anchor="iana-cons" numbered="true" toc="default">
      <name>IANA Considerations</name>
      <t>With the background and processes described in earlier sections, this
      document requests IANA
      has taken the following IANA Actions.</t>

      <t>Editor's Note: Mock-ups of the implementation of this set of requests actions.</t>

      <section numbered="true" toc="default">
        <name>Registry Group</name>
<!-- [rfced] We have been prepared with IANA's help during development of this memo, a few questions regarding Section 10.1 and
      have been captured in
<https://www.iana.org/assignments/performance-metrics>:

a) IANA shows the Proceedings registry title as Performance Metrics.  May we update this
text to use "Performance Metrics" instead of IPPM working group sessions. "PERFORMANCE METRICS Group"?

b) The IANA page does not specify general registration procedures; each
registry specifies that the registration procedure is currently preparing Specification Required, lists the
registry experts, and the reference.  Should the text be updated to indicate
that this information applies to each of the registries
appearing in the Performance Metrics registry, or perhaps each
subsection should specify the registration procedures for the given registry?
Is it possible that a mock-up. A recent version is available
      here: http://encrypted.net/IETFMetricsRegistry-106.html</t>

      <section title="Registry Group">
        <t>The new registry will be introduced in the future and have a
different registration procedure?

c) Please let us know how "TBD" should be updated.

Original:

10.1.  Registry Group

   The new registry group SHALL be named, "PERFORMANCE METRICS Group".

   Registration Procedure: Specification Required

   Reference: <This RFC>

   Experts: Performance Metrics Experts

   Note: TBD
-->
        <t>The new Registry group <bcp14>SHALL</bcp14> be named "PERFORMANCE METRICS
        Group".</t>
        <t>Registration Procedure: Specification Required</t>
        <t>Reference: &lt;This RFC&gt;</t> RFC 8911</t>
        <t>Experts: Performance Metrics Experts</t>
        <t>Note: TBD</t>
<t>Note that this applies to all of the Registries in the Performance Metrics
Group.</t>
      </section>
      <section title="Performance Metric numbered="true" toc="default">
        <name>Performance Metrics Name Elements"> Elements</name>
        <t>This document specifies the procedure for Performance Metrics Name
        Element Registry setup. IANA is requested to create a new set of
        registries for Performance Metric Name
	Elements called "Registered
        Performance Metric Name Elements". Each Registry, whose names are
        listed below:</t>

        <t><list style="empty">
            <t>MetricType:</t>

            <t>Method:</t>

            <t>SubTypeMethod:</t>

            <t>Spec:</t>

            <t>Units:</t>

            <t>Output:</t>
          </list></t>

        <t>will Registries. IANA has created
        the the following registries, which contain the current set of
	possibilities for Performance Metrics Registry Entry Names.</t> names.</t>
        <ul empty="true" spacing="normal">
          <li>Metric Type</li>
          <li>Method</li>
          <li>SubTypeMethod</li>
          <li>Spec</li>
          <li>Units</li>
          <li>Output</li>
        </ul>
        <t>To populate the Registered Performance Metric Metrics Name Elements at
        creation, the IANA is asked to use the lists of values for each name
        element Name
        Element listed in Section 7.1.2. <xref target="name-sec7-1-2"/>. The Name Elements in each registry Registry
        are case-sensitive.</t> case sensitive.</t>
        <t>When preparing a Metric entry Entry for Registration, registration, the developer
        SHOULD
        <bcp14>SHOULD</bcp14> choose Name elements Elements from among the registered elements.
        However, if the proposed metric is unique in a significant way, it may
        be necessary to propose a new Name element Element to properly describe the
        metric, as described below.</t>

        <t>A

<!-- [rfced] Please clarify "for IANA and Expert Review".  Does this mean the
document is provided to IANA and the Experts for review?  Perhaps that part of
the sentence can be deleted, because the second sentence indicates that
registrations are administered by IANA via the Specification Required policy,
which includes an Expert Review?

Current:
   A candidate Metric Entry metric entry RFC or immutable document for IANA and
   Expert Review would propose one or more new element values required
   to describe the unique entry, and the new name element(s) Name Element(s) would be
   reviewed along with the metric entry.  New assignments for Registered
   Performance Metric Metrics Name Elements will be administered by IANA
   through the Specification Required policy [RFC8126] (which includes
   Expert Review) <xref
        target="RFC8126"/>, Review, i.e., review by one of a group of experts, experts - in the
   case of this document, the Performance Metrics Experts, who are
   appointed by the IESG upon recommendation of the Transport Area
   Directors).
-->

        <t>A candidate Metric Entry RFC or an immutable document provided
	to IANA and Expert Review would propose one or
	more new element values required to
        describe the unique entry, and the new Name Element(s) would be
        reviewed along with the Metric Entry. New assignments for Registered
        Performance Metrics Name Elements will be administered by IANA through
        the Specification Required policy <xref target="RFC8126"
        format="default"/> (which includes Expert Review, i.e., review by one
        of a group of experts -- in the case of this document, the
        Performance Metrics Experts, who are appointed by the IESG upon
        recommendation of the Transport Area Directors.</t> Directors).</t>
      </section>
      <section title="New numbered="true" toc="default">
        <name>New Performance Metrics Registry"> Registry</name>
        <t>This document specifies the procedure for Performance Metrics
        Registry setup. IANA is requested to create a new registry for Performance Metrics called "Performance Metrics Registry". This Summary Registry.
        The Registry will contain contains the following Summary columns:</t>

        <t><list style="empty">
            <t>Identifier:</t>

            <t>Name:</t>

            <t>URI:</t>

            <t>Description:</t>

            <t>Reference:</t>

            <t>Change Controller:</t>

            <t>Version:</t>
          </list>Descriptions
        <ul empty="true" spacing="normal">
          <li>Identifier</li>
          <li>Name</li>
          <li>URI</li>
          <li>Description</li>
          <li>Reference</li>
          <li>Change Controller</li>
          <li>Version</li>
        </ul>
        <t>Descriptions of these columns and additional information
        found in the template for registry entries Registry Entries (categories and columns)
        are further defined in section <xref target="columns"/>.</t> target="columns" format="default"/>.</t>

        <t>The Identifier 0 should be Reserved. The Registered Performance
        Metric unique identifier Identifier is an unbounded integer (range 0 to
        infinity). The Identifier values from 64512 to 65536 are reserved for
        private or experimental use, and the user may encounter overlapping
        uses. When adding newly new Registered Performance Metrics to the
        Performance Metrics Summary Registry, IANA SHOULD <bcp14>SHOULD</bcp14> assign the lowest available
        identifier
        Identifier to the new Registered Performance Metric. If a Performance
        Metrics Expert providing review determines that there is a reason to
        assign a specific numeric identifier, Identifier, possibly leaving a temporary gap
        in the numbering, then the Performance Metrics Expert SHALL <bcp14>SHALL</bcp14> inform IANA of
        this decision.</t>
        <t>Names starting with the prefix Priv_ "Priv_" are reserved for private use, use
        and are not considered for registration. The "Name" Name column entries are
        further defined in section <xref target="columns"/>.</t> target="columns" format="default"/>.</t>
        <t>The "URI" URI column will have a URL to the full template of each
        Registry Entry.

<!-- [rfced] In speaking with IANA, our understanding is that "The Registry
Entry text SHALL be HTMLized" refers to the Registry Entry template.  May we
update the text to refer to the template rather than text?  Also, is it
correct for the parenthetical text to remain in the document; i.e., is it
correct to indicate how the conversion may be done?

Current:
   The registry entry. entry text SHALL be HTMLized to aid the reader,
   with links to reference RFCs (similar to the way that Internet-Drafts
   are HTMLized, the same tool can perform the function) or an immutable
   document.

Suggested
   The registry entry template SHALL be HTMLized to aid the reader,
   with links to reference RFCs (similar to the way that Internet-Drafts
   are HTMLized, the same tool can perform the function) or an immutable
   document.

In addition, should the URI template in Section 11.1.3 be updated to be more
specific to the Perfomance Metrics Registry?

Current:
   URL: https://www.iana.org/ ... <name>

Perhaps:
   URL: https://www.iana.org/assignments/performance-metrics/ ... <name>
-->

The Registry Entry text SHALL <bcp14>SHALL</bcp14> be HTML-ized HTMLized to aid the
        reader, with links to reference RFCs (similar to the way that Internet
        Drafts
        Internet-Drafts are HTML-ized, HTMLized, the same tool can perform the function)
        or an
        immutable document.</t>
        <t>The &ldquo;Reference&rdquo; Reference column will include an RFC number, an
        approved specification designator from another standards body, or
        some other immutable document.</t>

        <t>New

<!-- [rfced] Is it correct that the experts may be identifid via a) the IESG
upon recommendation by the Transport ADs or b) Standards Action?  Does b) mean
a Standards Track document would be written to identify?

Current:
   New assignments for the Performance Metrics Registry will be
   administered by IANA through the Specification Required policty policy
   [RFC8126] (which includes Expert Review) Review, i.e., review by one of a
   group of experts - in the case of this document, the Performance
   Metrics Experts, who are appointed by the IESG upon recommendation of
   the Transport Area Directors) or by Standards Action.
-->
        <t>New assignments for the Performance Metrics Summary Registry will be
        administered by IANA through the Specification Required policy
        <xref target="RFC8126"/>, target="RFC8126" format="default"/> (which includes Expert
        Review, i.e., review by one of a group of experts, experts -- in the case of
        this document, the Performance Metric Metrics Experts, who are
        appointed by the IESG upon recommendation of the Transport Area
        Directors,
        Directors) or by Standards Action. The experts can be initially drawn
        from the Working Group Chairs, document editors, and members of the
        Performance Metrics Directorate, among other sources of experts.</t>
        <t>Extensions of to the Performance Metrics Summary Registry require IETF
        Standards Action. Only one form of registry Registry extension is
        envisaged:</t>

        <t><list style="numbers">
            <t>Adding
        <ul empty="false" spacing="normal">
          <li>Adding columns, or both categories and columns, to accommodate
            unanticipated aspects of new measurements and metric
            categories.</t>
          </list>If
            categories.</li>
        </ul>
        <t>If the Performance Metrics Summary Registry is extended in this way,
        the Version version number of future entries complying with the extension
        SHALL
        <bcp14>SHALL</bcp14> be incremented (either in (in either the unit or the tenths digit, depending on
        the degree of extension.</t> extension).</t>
      </section>
    </section>
    <section title="Blank anchor="blank-reg-template" numbered="true" toc="default">
      <name>Blank Registry Template"> Template</name>
      <t>This section provides a blank template to help IANA and registry
      entry Registry
      Entry writers.</t>
      <section title="Summary"> numbered="true" toc="default">
        <name>Summary</name>
        <t>This category includes multiple indexes to the registry entry: Registry Entry: the
        element ID and metric name.</t> Metric Name.</t>
        <section title="ID (Identifier)"> numbered="true" toc="default">
          <name>ID (Identifier)</name>
          <t>&lt;insert a numeric identifier, Identifier, an integer, TBD&gt;</t>
        </section>
        <section title="Name"> numbered="true" toc="default">
          <name>Name</name>
          <t>&lt;insert name the Name, according to the metric naming convention&gt;</t>
        </section>
        <section title="URI"> numbered="true" toc="default">
          <name>URI</name>
          <t>URL: https://www.iana.org/ <eref target="https://www.iana.org/"/>
          ... &lt;name&gt;</t> &lt;Name&gt;</t>
        </section>
        <section title="Description"> numbered="true" toc="default">
          <name>Description</name>
          <t>&lt;provide a description&gt;</t>
        </section>
        <section title="Change Controller">
          <t/> numbered="true" toc="default">
          <name>Reference</name>
          <t>&lt;provide the RFC or other specification that contains the approved
          candidate Registry Entry&gt;</t>
        </section>
        <section numbered="true" toc="default">
          <name>Change Controller</name>
          <t>&lt;provide information regarding the entity responsible for
          approving revisions to the Registry Entry (including contact information for an individual, where appropriate)&gt;</t>
        </section>
        <section title="Version numbered="true" toc="default">
          <name>Version (of Registry Format)">
          <t/> Format)</name>
        </section>
      </section>

      <section title="Metric Definition"> numbered="true" toc="default">
        <name>Metric Definition</name>
        <t>This category includes columns to prompt the entry of all necessary
        details related to the metric definition, including the immutable
        document reference and values of input factors, called fixed
        parameters.</t> "Fixed
        Parameters".</t>
        <section title="Reference Definition">
          <t>&lt;Full numbered="true" toc="default">
          <name>Reference Definition</name>
          <t>&lt;provide a full bibliographic reference to an immutable doc.&gt;</t>

          <t>&lt;specific document&gt;</t>
          <t>&lt;provide a specific section reference and additional clarifications, if
          needed&gt;</t>

          <t/>
        </section>
        <section title="Fixed Parameters"> numbered="true" toc="default">
          <name>Fixed Parameters</name>
          <t>&lt;list and specify Fixed Parameters, input factors that must be
          determined and embedded in the measurement system for use when
          needed&gt;</t>
        </section>
      </section>
      <section title="Method numbered="true" toc="default">
        <name>Method of Measurement"> Measurement</name>
        <t>This category includes columns for references to relevant sections
        of the immutable documents(s) document&wj;(s) and any supplemental information needed
        to ensure an unambiguous methods method for implementations.</t>
        <section title="Reference Method"> numbered="true" toc="default">
          <name>Reference Method</name>
          <t>&lt;for the metric, insert relevant section references and
          supplemental info&gt;</t>
        </section>
        <section title="Packet numbered="true" toc="default">
          <name>Packet Stream Generation">
          <t>&lt;list Generation</name>
          <t>&lt;provide a list of generation parameters Parameters and section/spec references if
          needed&gt;</t>
        </section>

        <section title="Traffic numbered="true" toc="default">
          <name>Traffic Filtering (observation) Details">
          <t>The (Observation) Details</name>
          <t>This category includes the measured results based on a filtered version of the packets
          observed, and this section reference provides the filter details (when
          present).</t>

          <t>&lt;section reference&gt;.</t>

          <t/>
          <t>&lt;provide a section reference&gt;</t>
        </section>
        <section title="Sampling Distribution"> numbered="true" toc="default">
          <name>Sampling Distribution</name>
          <t>&lt;insert time distribution details, or how this is diff different from
          the filter&gt;</t>

          <t/>
        </section>
        <section title="Run-time numbered="true" toc="default">
          <name>Runtime Parameters and Data Format">
          <t>Run-time Format</name>
          <t>Runtime Parameters are input factors that must be determined,
          configured into the measurement system, and reported with the
          results for the context to be complete.</t>

          <t>&lt;list
          <t>&lt;provide a list of run-time parameters, Runtime Parameters and their data formats&gt;</t>

          <t/>
        </section>

        <section title="Roles">
          <t>&lt;lists numbered="true" toc="default">
          <name>Roles</name>
          <t>&lt;list the names of the different roles from the measurement
          method&gt;</t>

          <t/> Measurement
          Method&gt;</t>
        </section>
      </section>

      <section title="Output"> numbered="true" toc="default">
        <name>Output</name>
        <t>This category specifies all details of the Output output of measurements
        using the metric.</t>

        <section title="Type"> numbered="true" toc="default">
          <name>Type</name>
          <t>&lt;insert the name of the output type, type -- raw results or a selected summary
          statistic&gt;</t>
        </section>

        <section title="Reference Definition"> numbered="true" toc="default">
          <name>Reference Definition</name>
          <t>&lt;describe the reference data format for each type of
          result&gt;</t>
        </section>

        <section title="Metric Units"> numbered="true" toc="default">
          <name>Metric Units</name>
          <t>&lt;insert units for the measured results, and provide the reference
          specification&gt;.</t>
          specification&gt;</t>
        </section>

        <section title="Calibration"> numbered="true" toc="default">
          <name>Calibration</name>
          <t>&lt;insert information on calibration&gt;</t>
        </section>
      </section>

      <section title="Administrative items">
        <t/> numbered="true" toc="default">
        <name>Administrative Items</name>
        <t>This category provides administrative information.</t>

        <section title="Status">
          <t>&lt;current numbered="true" toc="default">
          <name>Status</name>
          <t>&lt;provide status: 'Current' or deprecated&gt;</t> 'Deprecated'&gt;</t>
        </section>

        <section title="Requester">
          <t>&lt;name or RFC, numbered="true" toc="default">
          <name>Requester</name>
          <t>&lt;provide a person's name, an RFC number, etc.&gt;</t>
        </section>

        <section title="Revision">
          <t>&lt;1.0&gt;</t> numbered="true" toc="default">
          <name>Revision</name>
          <t>&lt;provide the revision number: 1.0&gt;</t>
        </section>

        <section title="Revision Date">
          <t>&lt;format YYYY-MM-DD&gt;</t> numbered="true" toc="default">
          <name>Revision Date</name>
          <t>&lt;provide the date, in YYYY-MM-DD format&gt;</t>
        </section>
      </section>

      <section title="Comments numbered="true" toc="default">
        <name>Comments and Remarks">
        <t>&lt;Additional (Informational) Remarks</name>
        <t>&lt;list any additional (informational) details for this entry&gt;</t>
      </section>
    </section>
  </middle>
  <back>
    <references>
      <name>References</name>
      <references>
        <name>Normative References</name>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.2026.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.2119.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.2330.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.3986.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8126.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.6390.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.6576.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.7799.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8174.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.5644.xml"/>
      </references>
      <references>
        <name>Informative References</name>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.7679.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.2681.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.3432.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.3550.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.3611.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.4148.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.5474.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.5475.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.5477.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.6035.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.6248.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.7012.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.7014.xml"/>
<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.7594.xml"/>

<!-- draft-ietf-ippm-initial-registry (RFC 8912) -->
        <reference anchor="RFC8912" target="https://www.rfc-editor.org/info/rfc8912">
          <front>
            <title>Initial Performance Metrics Registry Entries</title>
            <author initials="A" surname="Morton" fullname="Alfred Morton">
              <organization/>
            </author>
            <author initials="M" surname="Bagnulo" fullname="Marcelo Bagnulo">
              <organization/>
            </author>
            <author initials="P" surname="Eardley" fullname="Philip Eardley">
              <organization/>
            </author>
            <author initials="K" surname="D'Souza" fullname="Kevin D'Souza">
              <organization/>
            </author>
            <date month="September" year="2020"/>
          </front>
          <seriesInfo name="RFC" value="8912"/>
          <seriesInfo name="DOI" value="10.17487/RFC8912"/>
        </reference>

<xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.6991.xml"/>
      </references>
    </references>
    <section title="Acknowledgments"> numbered="false" toc="default">
      <name>Acknowledgments</name>
      <t>Thanks to Brian Trammell and Bill Cerveny, <contact fullname="Brian Trammell"/> and
      <contact fullname="Bill Cerveny"/>, IPPM chairs, for leading
      some brainstorming sessions on this topic. Thanks to Barbara Stark and
      Juergen Schoenwaelder
      <contact fullname="Barbara Stark"/> and
      <contact fullname="Juergen Schoenwaelder"/> for the detailed feedback
      and suggestions. Thanks to Andrew McGregor <contact fullname="Andrew McGregor"/> for
      suggestions on metric naming. Thanks to Michelle
      Cotton <contact fullname="Michelle
      Cotton"/> for her early IANA review, and to Amanda Barber <contact fullname="Amanda
      Baber"/> for answering questions related to the presentation of the registry
      Registry and accessibility of the complete template via URL. Thanks to Roni Even
      <contact fullname="Roni Even"/> for his review and suggestions to
      generalize the procedures. Thanks to ~all all of the Area Directors for
      their reviews.</t>
    </section>

    <!--
    <section title="Appendix: Examples">

	    <section title="Example IPPM Active Registry Entry">
	      <t>This section is Informational.</t>

	      <t>This section gives an example registry entry for the active metric
	      described in <xref target="RFC3393"/>, on Packet Delay Variation.</t>

	      <section title="Registry Indexes">
	        <t>This category includes multiple indexes to the Registered Performance Metrics,
	        the element ID and metric name.</t>

	        <section title="Identifier">
	          <t>An integer having enough digits to uniquely identify each entry
	          in the Registry.</t>
	        </section>

	        <section title="Name">
	          <t>A metric naming convention is TBD.</t>

	          <t>One possibility based on IPPM's framework is:</t>

	          <t>Act_IP_UDP_One-way-pdv_95th-percentile_Poisson</t>
	        </section>

	        <section title="URI">
	          <t>Prefix urn:ietf:params:performance:metric</t>
	        </section>

	        <section title="Status">
	          <t>current</t>
	        </section>

	        <section title="Requestor">
	          <t>Alcelip Mornuley</t>
	        </section>

	        <section title="Revision">
	          <t>1.0</t>
	        </section>

	        <section title="Revision Date">
	          <t>2014-07-04</t>
	        </section>

	        <section title="Description">
	          <t>An assessment of packet delay variation with respect to the
	          minimum delay observed on the stream.</t>
	        </section>

	        <section title="Reference Specification(s)">
	          <t><xref target="RFC2330"/><xref target="RFC3393"/><xref
	          target="RFC5481"/><xref target="RFC5905"/></t>
	        </section>
	      </section>

	      <section title="Metric Definition">
	        <t>This category includes columns to prompt the entry of all necessary
	        details related to the metric definition, including the RFC reference
	        and values of input factors, called fixed parameters.</t>

	        <section title="Reference Definition">
	          <t>See sections 2.4 and 3.4 of <xref target="RFC3393"/>. Singleton
	          delay differences measured are referred to by the variable name
	          "ddT".</t>
	        </section>

	        <section title="Fixed Parameters">
	          <t>Since the metric's reference supplies a list of Parameters as
	          part of its descriptive template, a sub-set of the Parameters have
	          been designated as designated as Fixed Parameters for this
	          entry.</t>

	          <t><list style="symbols">
	              <t>F, a selection function defining unambiguously the packets
	              from the stream selected for the metric. See section 4.2 of
	              <xref target="RFC5481"/> for the PDV form.</t>

	              <t>L, a packet length in bits. L = 200 bits.</t>

	              <t>Tmax, a maximum waiting time for packets to arrive at Dst,
	              set sufficiently long to disambiguate packets with long delays
	              from packets that are discarded (lost). Tmax = 3 seconds.</t>

	              <t>Type-P, as defined in <xref target="RFC2330"/>, which
	              includes any field that may affect a packet's treatment as it
	              traverses the network. The packets are IP/UDP, with DSCP = 0
	              (BE).</t>
	            </list></t>
	        </section>
	      </section>

	      <section title="Method of Measurement">
	        <t>This category includes columns for references to relevant sections
	        of the RFC(s) and any supplemental information needed to ensure an
	        unambiguous methods for implementations.</t>

	        <section title="Reference Method">
	          <t>See section 2.6 and 3.6 of <xref target="RFC3393"/> for singleton
	          elements.</t>
	        </section>

	        <section title="Stream Type and Stream Parameters">
	          <t>Poisson distributed as described in <xref target="RFC2330"/>,
	          with the following Parameters.</t>

	          <t><list style="symbols">
	              <t>lambda, a rate in reciprocal seconds (for Poisson Streams).
	              lambda = 1 packet per second</t>

	              <t>Upper limit on Poisson distribution (values above this limit
	              will be clipped and set to the limit value). Upper limit = 30
	              seconds.</t>
	            </list></t>
	        </section>

			<section title="Traffic Filter">
				<t>NA</t>
			</section>

			<section title="Measurement Timing">
				<t>NA</t>
			</section>

	        <section title="Output Type and Data Format">
	          <t>See section 4.3 of <xref target="RFC3393"/> for details on the
	          percentile statistic.</t>

	          <t>The percentile = 95.</t>

	          <t>Data format is a 32-bit unsigned floating point value.</t>

	          <t>Individual results (singletons) should be represented by the
	          following triple</t>

	          <t><list style="symbols">
	              <t>T1 and T2, times as described below in the Run-time
	              parameters section.</t>

	              <t>ddT as defined in section 2.4 of <xref target="RFC3393"/></t>
	            </list>if needed. The result format for ddT is *similar to* the
	          short format in <xref target="RFC5905"/> (32 bits) and is as
	          follows: the first 16 bits represent the *signed* integer number of
	          seconds; the next 16 bits represent the fractional part of a
	          second.</t>
	        </section>

	        <section title="Metric Units">
	          <t>See section 3.3 of <xref target="RFC3393"/> for singleton
	          elements.</t>

	          <t><xref target="RFC2330"/> recommends that when a time is given, it
	          will be expressed in UTC.</t>

	          <t>The timestamp format (for T, Tf, etc.) is the same as in <xref
	          target="RFC5905"/> (64 bits) and is as follows: the first 32 bits
	          represent the unsigned integer number of seconds elapsed since 0h on
	          1 January 1900; the next 32 bits represent the fractional part of a
	          second that has elapsed since then.</t>
	        </section>

	        <section title="Run-time Parameters and Data Format">
	          <t>Since the metric's reference supplies a list of Parameters as
	          part of its descriptive template, a sub-set of the Parameters have
	          been designated as Run-Time Parameters for this entry. In related
	          Registered Performance Metrics, some of the parameters below may be designated as
	          Fixed Parameters instead.</t>

	          <t><list style="symbols">
	              <t>Src, the IP address of a host (32-bit value for IPv4, 128-bit
	              value for IPv6)</t>

	              <t>Dst, the IP address of a host (32-bit value for IPv4, 128-bit
	              value for IPv6)</t>

	              <t>T, a time (start of test interval, 128-bit NTP Date Format,
	              see section 6 of <xref target="RFC5905"/>)</t>

	              <t>Tf, a time (end of test interval, 128-bit NTP Date Format,
	              see section 6 of <xref target="RFC5905"/>)</t>

	              <t>T1, the wire time of the first packet in a pair, measured at
	              MP(Src) as it leaves for Dst (64-bit NTP Timestamp Format, see
	              section 6 of <xref target="RFC5905"/>).</t>

	              <t>T2, the wire time of the second packet in a pair, measured at
	              MP(Src) as it leaves for Dst (64-bit NTP Timestamp Format, see
	              section 6 of <xref target="RFC5905"/>).</t>

	              <t>I(i),I(i+1), i &gt;=0, pairs of times which mark the
	              beginning and ending of the intervals in which the packet stream
	              from which the measurement is taken occurs. Here, I(0) = T0 and
	              assuming that n is the largest index, I(n) = Tf (pairs of 64-bit
	              NTP Timestamp Format, see section 6 of <xref target="RFC5905"/>).</t>
	            </list></t>
	        </section>
	      </section>

	      <section title="Comments and Remarks">
	        <t>Lost packets represent a challenge for delay variation metrics. See
	        section 4.1 of <xref target="RFC3393"/> and the delay variation
	        applicability statement<xref target="RFC5481"/> for extensive analysis
	        and comparison of PDV and an alternate metric, IPDV.</t>
	      </section>
	    </section>

	    <section title="Example RTCP-XR Registry Entry">
	      <t>This section is Informational.</t>

	      <t>This section gives an example registry entry for the end-point metric
	      described in <xref target="RFC7003"/>, for RTCP-XR Burst/Gap
	      Discard Metric reporting.</t>

	      <section title="Registry Indexes">
	        <t>This category includes multiple indexes to the Registered Performance Metrics,
	        the element ID and metric name.</t>

	        <section title="Identifier">
	          <t>An integer having enough digits to uniquely identify each entry
	          in the Registry.</t>
	        </section>

	        <section title="Name">
	          <t>A metric naming convention is TBD.</t>
	        </section>

	        <section title="URI">
	          <t>Prefix urn:ietf:params:performance:metric</t>
	        </section>

	        <section title="Status">
	          <t>current</t>
	        </section>

	        <section title="Requestor">
	          <t>Alcelip Mornuley</t>
	        </section>

	        <section title="Revision">
	          <t>1.0</t>
	        </section>

	        <section title="Revision Date">
	          <t>2014-07-04</t>
	        </section>

	        <section title="Description">
	          <t>TBD.</t>
	        </section>

	        <section title="Reference Specification(s)">
	          <t><xref target="RFC3611"/><xref target="RFC4566"/>
              <xref target="RFC6776"/><xref target="RFC6792"/>
              <xref target="RFC7003"/></t>
	        </section>
	      </section>

	      <section title="Metric Definition">
	        <t>This category includes columns to prompt the entry of all necessary
	        details related to the metric definition, including the RFC reference
	        and values of input factors, called fixed parameters. Section 3.2 of
	        <xref target="RFC7003"/> provides the reference information for this
	        category.</t>

	        <section title="Reference Definition">
	          <t>Packets Discarded in Bursts:</t>

	          <t>The total number of packets discarded during discard bursts. The
	          measured value is unsigned value. If the measured value exceeds
	          0xFFFFFD, the value 0xFFFFFE MUST be reported to indicate an
	          over-range measurement. If the measurement is unavailable, the value
	          0xFFFFFF MUST be reported.</t>
	        </section>

	        <section title="Fixed Parameters">
	          <t>Fixed Parameters are input factors that must be determined and
	          embedded in the measurement system for use when needed. The values
	          of these parameters is specified in the Registry.</t>

	          <t>Threshold: 8 bits, set to value = 3 packets.</t>

	          <t>The Threshold is equivalent to Gmin in [RFC3611], i.e., the
	          number of successive packets that must not be discarded prior to and
	          following a discard packet in order for this discarded packet to be
	          regarded as part of a gap. Note that the Threshold is set in
	          accordance with the Gmin calculation defined in Section 4.7.2 of
	          [RFC3611].</t>

	          <t>Interval Metric flag: 2 bits, set to value 11=Cumulative
	          Duration</t>

	          <t>This field is used to indicate whether the burst/gap discard
	          metrics are Sampled, Interval, or Cumulative metrics <xref target="RFC6792"/>:</t>

	          <t>I=10: Interval Duration - the reported value applies to the most
	          recent measurement interval duration between successive metrics
	          reports.</t>

	          <t>I=11: Cumulative Duration - the reported value applies to the
	          accumulation period characteristic of cumulative measurements.</t>

	          <t>Senders MUST NOT use the values I=00 or I=01.</t>
	        </section>
	      </section>

	      <section title="Method of Measurement">
	        <t>This category includes columns for references to relevant sections
	        of the RFC(s) and any supplemental information needed to ensure an
	        unambiguous methods for implementations. For the Burst/Gap Discard
	        Metric, it appears that the only guidance on methods of measurement is
	        in Section 3.0 of <xref target="RFC7003"/> and its supporting
	        references. Relevant information is repeated below, although there
	        appears to be no section titled "Method of Measurement" in <xref
	        target="RFC7003"/>.</t>

	        <section title="Reference Method">
	          <t>Metrics in this block report on burst/gap discard in the stream
	          arriving at the RTP system. Measurements of these metrics are made
	          at the receiving end of the RTP stream. Instances of this metrics
	          block use the synchronization source (SSRC) to refer to the separate
	          auxiliary Measurement Information Block <xref target="RFC6776"/>, which
              describes measurement periods in use (see <xref target="RFC6776"/>,
              Section 4.2).</t>

	          <t>This metrics block relies on the measurement period in the
	          Measurement Information Block indicating the span of the report.
	          Senders MUST send this block in the same compound RTCP packet as the
	          Measurement Information Block. Receivers MUST verify that the
	          measurement period is received in the same compound RTCP packet as
	          this metrics block. If not, this metrics block MUST be
	          discarded.</t>
	        </section>

	        <section title="Stream Type and Stream Parameters">
	          <t>Since RTCP-XR Measurements are conducted on live RTP traffic, the
	          complete description of the stream is contained in SDP messages that
	          proceed the establishment of a compatible stream between two or more
	          communicating hosts. See Run-time Parameters, below.</t>
	        </section>

			<section title="Traffic Filter">
				<t>NA</t>
			</section>

			<section title="Measurement Timing">
				<t>NA</t>
			</section>

	        <section title="Output Type and Data Format">
	          <t>The output type defines the type of result that the metric
	          produces.</t>

	          <t><list style="symbols">
	              <t>Value: Packets Discarded in Bursts</t>

	              <t>Data Format: 24 bits</t>

	              <t>Reference: Section 3.2 of <xref target="RFC7003"/></t>
	            </list></t>
	        </section>

	        <section title="Metric Units">
	          <t>The measured results are apparently expressed in packets,
	          although there is no section of <xref target="RFC7003"/> titled
	          "Metric Units".</t>
	        </section>

	        <section title="Run-time Parameters and Data Format">
	          <t>Run-Time Parameters are input factors that must be determined,
	          configured into the measurement system, and reported with the
	          results for the context to be complete. However, the values of these
	          parameters is not specified in the Registry, rather these parameters
	          are listed as an aid to the measurement system implementor or user
	          (they must be left as variables, and supplied on execution).</t>

	          <t>The Data Format of each Run-time Parameter SHALL be specified in
	          this column, to simplify the control and implementation of
	          measurement devices.</t>

	          <t>SSRC of Source: 32 bits As defined in Section 4.1 of
	          [RFC3611].</t>

	          <t>SDP Parameters: As defined in <xref target="RFC4566"/></t>

	          <t>Session description v= (protocol version number, currently only
	          0)</t>

	          <t>o= (originator and session identifier : username, id, version
	          number, network address)</t>

	          <t>s= (session name : mandatory with at least one UTF-8-encoded
	          character)</t>

	          <t>i=* (session title or short information) u=* (URI of
	          description)</t>

	          <t>e=* (zero or more email address with optional name of
	          contacts)</t>

	          <t>p=* (zero or more phone number with optional name of
	          contacts)</t>

	          <t>c=* (connection information&mdash;not required if included in all
	          media)</t>

	          <t>b=* (zero or more bandwidth information lines) One or more Time
	          descriptions ("t=" and "r=" lines; see below)</t>

	          <t>z=* (time zone adjustments)</t>

	          <t>k=* (encryption key)</t>

	          <t>a=* (zero or more session attribute lines)</t>

	          <t>Zero or more Media descriptions (each one starting by an "m="
	          line; see below)</t>

	          <t>m= (media name and transport address)</t>

	          <t>i=* (media title or information field)</t>

	          <t>c=* (connection information &mdash; optional if included at
	          session level)</t>

	          <t>b=* (zero or more bandwidth information lines)</t>

	          <t>k=* (encryption key)</t>

	          <t>a=* (zero or more media attribute lines &mdash; overriding the
	          Session attribute lines)</t>

	          <t>An example Run-time SDP description follows:</t>

	          <t>v=0</t>

	          <t>o=jdoe 2890844526 2890842807 IN IP4 192.0.2.5</t>

	          <t>s=SDP Seminar i=A Seminar on the session description protocol</t>

	          <t>u=http://www.example.com/seminars/sdp.pdf e=j.doe@example.com
	          (Jane Doe)</t>

	          <t>c=IN IP4 233.252.0.12/127</t>

	          <t>t=2873397496 2873404696</t>

	          <t>a=recvonly</t>

	          <t>m=audio 49170 RTP/AVP 0</t>

	          <t>m=video 51372 RTP/AVP 99</t>

	          <t>a=rtpmap:99 h263-1998/90000</t>
	        </section>
	      </section>

	      <section title="Comments and Remarks">
	        <t>TBD.</t>
	      </section>
	    </section>

		<section title="Example Generalized Passive Octet Count Entry">

			<t>This section gives an example registry entry for a generalized the passive metric
				octetDeltaCount described in the IPFIX registry"/>.</t>

			<section title="Registry Indexes">
				<t>This category includes multiple indexes to the Registered Performance Metrics,
					the element ID and metric name.</t>

				<section title="Element Identifier">
					<t>An integer having enough digits to uniquely identify each entry
						in the Registry.</t>
					<t>TBD by IANA.</t>
				</section>

				<section title="Metric Name">
					<t>A metric naming convention is TBD.</t>

					<t>Pas_IP_Octet-Delta-General</t>

				</section>

				<section title="URI">
					<t>urn:ietf:params:performance:metric-something</t>
				</section>

				<section title="Status">
					<t>Current</t>
				</section>

				<section title="Requester">
					<t>TBD</t>
				</section>

				<section title="Revision">
					<t>0</t>
				</section>

				<section title="Revision Date">
					<t>TBD</t>
				</section>

				<section title="Metric Description">
					<t>A delta count of the number of octets observed.
					</t>
				</section>

				<section title="Reference Specification(s)">
					<t>octetDeltaCount described in the IPFIX registry.</t>
				</section>

			</section>

			<section title="Metric Definition">
				<t>This category includes columns to prompt the entry of all necessary
					details related to the metric definition, including the RFC reference
					and values of input factors, called fixed parameters.</t>

				<section title="Reference Definition">

					<t>octetDeltaCount described in the IPFIX registry.</t>

				</section>

				<section title="Fixed Parameters">

					<t> As this is the generalised version of the IP delta count
						metric, there are no fixed parameters.</t>

				</section>
			</section>

			<section title="Method of Measurement">

				<section title="Reference Implementation">
					<t>For &lt;metric&gt;.</t>

					<t>&lt;section reference&gt;</t>

					<t/>
				</section>

 				<section title="Stream Type and Stream Parameters">
					<t>NA</t>
				</section>

				<section title="Traffic Filter Criteria">
					<t>
						This measurement only covers IP packets and the IP
						payload (including the IP header) of these packets.

						Non-IP packets (BPDUs, ISIS) will not be accounted.
						Layer 2 overhead (Ethernet headers, MPLS, QinQ, etc.) will
						also not be represented in the measurement.
					</t>
				</section>

				<section title="Measurement Timing">
					<t>
						This is a continous measurement of the IP octets
						seen in the traffic selection scope (run-time parameter).
					</t>
					<t>The measurement interval is a run time parameter.
					</t>
					<t>There is no sampling.</t>

				</section>

				<section title="Output Type(s) and Data Format">
					<t>It is possible that multiple observation intervals are reported
						in a single report. In such a case concatination of the interval reports
						(deltaOctetCount, start-time, end-time) is allowed. </t>

					<t>The delta octet count metric reports a observation
						start time and end time. </t>

					<t><list style="symbols">
							<t>Value: observation-start-time and observation-end-time</t>

							<t>Data Format: 64-bit NTP Time-stamp Format</t>

							<t>Reference: section 6 of
								<xref target="RFC5905"/></t>
						</list></t>

				</section>

				<section title="Metric Units">
					<t>The measured results are expressed in octets with
						a data format of unsigned64 as described in the IPFIX registry.</t>

				</section>

				<section title="Run-time Parameters and Data Format">
					<t>Run-time Parameters are input factors that must be determined,
						configured into the measurement system, and reported with the
						results for the context to be complete.</t>

					<t><list style="symbols">
							<t>samplingTimeInterval, length of time a single report covers. unsigned32 microseconds <xref target="RFC5477"/> </t>
							<t>observationInterface, ifindex of interface to monitor. -1 represents all interfaces. -2 representing WAN facing and -3 represents LAN facing. unsigned32.</t>
							<t>observation direction, unsigned8 where 0 represents incoming traffic on interface, 1 outgoing and 2 represents both incoming and outgoing. </t>
						</list></t>
				</section>
			</section>

			<section title="Comments and Remarks">
				<t>Additional (Informational) details for this entry</t>
			</section>

		</section>

		<section title="Example 5min Passive Egress IP Destination Octet Count Entry on WAN Interface">
			<t>tbd</t>

			<t>This section is Informational.</t>

			<t>This section gives an example registry entry for the passive accounting of byte counts and
				destination address on outgoing WAN IP. The byte count and IP address is based on octetDeltaCount
				and destinationIPv4Address, as described in the IPFIX registry.</t>

			<section title="Registry Indexes">
				<t>This category includes multiple indexes to the Registered Performance Metrics,
					the element ID and metric name.</t>

				<section title="Element Identifier">
					<t>An integer having enough digits to uniquely identify each entry
						in the Registry.</t>
					<t>TBD by IANA.</t>
				</section>

				<section title="Metric Name">
					<t>A metric naming convention is TBD.</t>

					<t>Pas_IPDst-Octet-Delta-WAN-egress</t>

				</section>

				<section title="URI">
					<t>urn:ietf:params:performance:Pas_IPDst-Octet-Delta-WAN-egress</t>
				</section>

				<section title="Status">
					<t>Current</t>
				</section>

				<section title="Requester">
					<t>The IPPM working group</t>
				</section>

				<section title="Revision">
					<t>0</t>
				</section>

				<section title="Revision Date">
					<t>Today</t>
				</section>

				<section title="Metric Description">
					<t>This example passive measurement registry entry measures per-destination IP bytes sent.
					The byte count and IP address are based on octetDeltaCount and destinationIPv4Address, as
					described in IPFIX Registry. This metric can be used to understand outgoing
					top destinations per agent, saturation of link utilization towards a single destination and
					other bandwidth utilization uses.</t>
				</section>

				<section title="Reference Specification(s)">
					<t>octetDeltaCount described in IPFIX registry</t>
				</section>

				<section title="Fixed Parameters">
					<t>Measurement Interval = 300 sec</t>
					<t>IPFIX Template = KEY:destinationIPv4Address,egressInterface=WAN  Value:octetDeltaCount </t>
				</section>

				<section title="Traffic Filter">
					<t>PSAMP: "ipVersion == 4 AND egressInterface==WAN"</t>
				</section>

				<section title="Sampling Distribution">
					<t>No sampling</t>
				</section>

				<section title="Run-time Parameters">
					<t>None</t>
				</section>

			</section>

			<section title="Example 5min Passive Egress Octet Count Entry on WAN Interface">
			<t>tbd</t>

			<t>This section is Informational.</t>

			<t>This section gives an example registry entry for accounting of outgoing WAN IP
				traffic the passive metric in terms of octetDeltaCount, as described in the IPFIX registry.</t>

			<section title="Registry Indexes">
				<t>This category includes multiple indexes to the Registered Performance Metrics,
					the element ID and metric name.</t>

				<section title="Element Identifier">
					<t>An integer having enough digits to uniquely identify each entry
						in the Registry.</t>
					<t>TBD by IANA.</t>
				</section>

				<section title="Metric Name">
					<t>A metric naming convention is TBD.</t>

					<t>Pas_IP-Octet-Delta-WAN-egress</t>

				</section>

				<section title="URI">
					<t>urn:ietf:params:performance:metric-something</t>
				</section>

				<section title="Status">
					<t>Current</t>
				</section>

				<section title="Requester">
					<t>TBD</t>
				</section>

				<section title="Revision">
					<t>0</t>
				</section>

				<section title="Revision Date">
					<t>TBD</t>
				</section>

				<section title="Metric Description">
					<t>A delta count of the number of octets observed outgoing on WAN interface.
					</t>
				</section>

				<section title="Reference Specification(s)">
					<t>octetDeltaCount described in the IPFIX registry</t>
				</section>

			</section>

			<section title="Metric Definition">
				<t>This category includes columns to prompt the entry of all necessary
					details related to the metric definition, including the RFC reference
					and values of input factors, called fixed parameters.</t>

				<section title="Reference Definition">

					<t>octetDeltaCount described in the IPFIX registry"/></t>

				</section>

				<section title="Fixed Parameters">

					<t> As this is a specific version of Pas_IP-Octet-Delta-General that
						performs metering of all outgoing WAN traffic.</t>

					<t><list style="symbols">
							<t>samplingTimeInterval= 300000000, length of time a single report covers. unsigned32 microseconds <xref target="RFC5477"/> </t>
							<t>observationInterface= -2, ifindex of interface to monitor. -1 represents all interfaces. -2 representings WAN facing and -3 represnets LAN facing. unsigned32.</t>
							<t>observation direction= 1, unsigned8 where 0 represents incoming traffic on interface, 1 outgoing and 2 represents both incoming and outgoing. </t>
						</list></t>

				</section>
			</section>

			<section title="Method of Measurement">

				<section title="Reference Implementation">
					<t>For &lt;metric&gt;.</t>

					<t>&lt;section reference&gt;</t>

					<t/>
				</section>

 				<section title="Stream Type and Stream Parameters">
					<t>NA</t>
				</section>

				<section title="Traffic Filter Criteria">
					<t>
						This measurement only covers IP packets observed in the
						WAN outgoing direction. The bytes counted are the IP
						payload (including the IP header) of these packets.

						Non-IP packets (BPDUs, ISIS) will not be accounted.
						Layer 2 overhead (Ethernet headers, MPLS, QinQ, etc.) will
						also not be represented in the measurement.
					</t>
				</section>

				<section title="Measurement Timing">
					<t>
						This is a continous measurement of the IP octets
						seen in the traffic selection scope (run-time parameter),
						each of a 5 minute duration.
					</t>
					<t>There is no sampling.</t>

				</section>

				<section title="Output Type(s) and Data Format">
					<t>It is possible that multiple observation intervals are reported
						in a single report. In such a case concatination of the interval reports
						(deltaOctetCount, start-time, end-time) is allowed. </t>

					<t>The delta octet count metric reports a observation
						start time and end time. </t>

					<t><list style="symbols">
							<t>Value: observation-start-time and observation-end-time</t>

							<t>Data Format: 64-bit NTP Time-stamp Format</t>

							<t>Reference: section 6 of
								<xref target="RFC5905"/></t>
						</list></t>

				</section>

				<section title="Metric Units">
					<t>The measured results are expressed in octets with
						a data format of unsigned64 as described in the IPFIX registry</t>

				</section>

				<section title="Run-time Parameters and Data Format">
					<t>There are no run-time parameters for this registry entry.</t>

				</section>
			</section>

			<section title="Comments and Remarks">
				<t>Additional (Informational) details for this entry</t>
			</section>

		</section>

		<section title="Example Passive RTP Lost Packet Count">
			<t>tbd</t>
		</section>

	    <section title="Example BLANK Registry Entry">
	      <t>This section is Informational. (?)</t>

	      <t>This section gives an example registry entry for the &lt;type of
	      metric and specification reference&gt; .</t>

	      <section title="Registry Indexes">
	        <t>This category includes multiple indexes to the Registered Performance Metrics,
	        the element ID and metric name.</t>

	        <section title="Identifier">
	          <t>An integer.</t>
	        </section>

	        <section title="Name">
	          <t>A metric naming convention is TBD.</t>
	        </section>

	        <section title="URI">
	          <t>Prefix urn:ietf:params:performance:metric</t>
	        </section>

	        <section title="Status">
	          <t>current</t>
	        </section>

	        <section title="Requestor">
	          <t>name or RFC, etc.</t>
	        </section>

	        <section title="Revision">
	          <t>1.0</t>
	        </section>

	        <section title="Revision Date">
	          <t>YYYY-MM-DD</t>
	        </section>

	        <section title="Description">
	          <t>TBD.</t>
	        </section>

	        <section title="Reference Specification(s)">
	          <t>RFC...</t>
	        </section>
	      </section>

	      <section title="Metric Definition">
	        <t>This category includes columns to prompt the entry of all necessary
	        details related to the metric definition, including the RFC reference
	        and values of input factors, called fixed parameters.</t>

	        <t>&lt;possible section reference&gt;.</t>

	        <section title="Reference Definition">
	          <t/>

	          <t/>
	        </section>

	        <section title="Fixed Parameters">
	          <t>Fixed Parameters are input factors that must be determined and
	          embedded in the measurement system for use when needed. The values
	          of these parameters is specified in the Registry.</t>

	          <t>&lt;list fixed parameters&gt;</t>
	        </section>
	      </section>

	      <section title="Method of Measurement">
	        <t>This category includes columns for references to relevant sections
	        of the RFC(s) and any supplemental information needed to ensure an
	        unambiguous methods for implementations.</t>

	        <section title="Reference Method">
	          <t>For &lt;metric&gt;.</t>

	          <t>&lt;section reference&gt;</t>

	          <t/>
	        </section>

	        <section title="Stream Type and Stream Parameters">
	          <t>&lt;list of stream parameters&gt;.</t>

	          <t>&lt;references&gt;</t>

	          <t/>
	        </section>

			<section title="Traffic Filter Criteria">
				<t>
					&lt;list filter criteria limitations and allowances &gt;
				</t>
			</section>

			<section title="Measurement Timing">
				<t>
					&lt; list timing requirements and limitations &gt;

				</t>
			</section>

	        <section title="Output Type and Data Format">
	          <t>The output type defines the type of result that the metric
	          produces.</t>

	          <t><list style="symbols">
	              <t>Value:</t>

	              <t>Data Format: (There may be some precedent to follow here, but
	              otherwise use 64-bit NTP Timestamp Format, see section 6 of
	              <xref target="RFC5905"/>).</t>

	              <t>Reference: &lt;section reference&gt;</t>
	            </list></t>
	        </section>

	        <section title="Metric Units">
	          <t>The measured results are expressed in &lt;units&gt;,</t>

	          <t>&lt;section reference&gt;.</t>
	        </section>

	        <section title="Run-time Parameters and Data Format">
	          <t>Run-time Parameters are input factors that must be determined,
	          configured into the measurement system, and reported with the
	          results for the context to be complete.</t>

	          <t>&lt;list of run-time parameters&gt;</t>

	          <t>&lt;reference(s)&gt;.</t>
	        </section>
	      </section>

	      <section title="Comments and Remarks">
	        <t>Additional (Informational) details for this entry</t>
	      </section>
	    </section>

    </section>
-->
  </middle>

  <back>
    <references title="Normative References">
      <?rfc include="reference.RFC.2026"?>

      <?rfc include="reference.RFC.2119"?>

      <?rfc ?>

      <?rfc include='reference.RFC.2330'?>

      <?rfc include='reference.RFC.3986'?>

      <?rfc ?>

      <?rfc include="reference.RFC.8126"?>

      <?rfc ?>

      <?rfc include="reference.RFC.6390"?>

      <?rfc include='reference.RFC.6576'?>

      <?rfc include='reference.RFC.7799'?>

      <?rfc include='reference.RFC.8174'?>
    </references>

    <references title="Informative References">
      <?rfc ?>

      <?rfc include='reference.RFC.7679'?>

      <?rfc include="reference.RFC.2681"?>

      <?rfc ?>

      <?rfc include="reference.RFC.3432"?>

      <?rfc include="reference.RFC.3550"?>

      <?rfc include="reference.RFC.3611"?>

      <?rfc include="reference.RFC.4148"?>

      <?rfc include="reference.RFC.5474"?>

      <?rfc include="reference.RFC.5475"?>

      <?rfc include="reference.RFC.5477"?>

      <?rfc ?>

      <?rfc ?>

      <?rfc include="reference.RFC.6035"?>

      <?rfc include="reference.RFC.6248"?>

      <?rfc ?>

      <?rfc ?>

      <?rfc include="reference.RFC.7012"?>

      <?rfc include="reference.RFC.7014"?>

      <?rfc include='reference.RFC.7594'?>

      <?rfc include='reference.RFC.8194'?>

      <?rfc ?>

      <?rfc include='reference.I-D.ietf-ippm-initial-registry'?>

      <?rfc include='reference.RFC.6991'?>
    </references>
  </back>

</rfc>