Network Working Group

Internet Engineering Task Force (IETF)                        M. Bagnulo
Internet-Draft
Request for Comments: 8911                                          UC3M
Intended status:
Category: Standards Track                                      B. Claise
Expires: September 10, 2020
ISSN: 2070-1721                                      Cisco Systems, Inc.
                                                              P. Eardley
                                                                      BT
                                                               A. Morton
                                                               AT&T Labs
                                                               A. Akhter
                                                              Consultant
                                                           March 9,
                                                            October 2020

                    Registry for Performance Metrics
                   draft-ietf-ippm-metric-registry-24

Abstract

   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.

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   https://www.rfc-editor.org/info/rfc8911.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   4
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   5
   3.  Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . .   7
   4.  Motivation  Motivations for a the Performance Metrics Registry . . . . . . . .   8
     4.1.  Interoperability  . . . . . . . . . . . . . . . . . . . .   8
     4.2.  Single point Point of reference Reference for Performance Metrics . . . .   9
     4.3.  Side benefits . . . . . . . . . . . . . . . . . . . . . .   9 Benefits
   5.  Criteria for Performance Metrics Registration . . . . . . . .   9
   6.  Performance Metric Metrics Registry: Prior attempt  . . . . . . . . .  10 Attempt
     6.1.  Why this This Attempt Should Succeed . . . . . . . . . . . . .  11
   7.  Definition of the Performance Metric Metrics Registry . . . . . . . .  11
     7.1.  Summary Category  . . . . . . . . . . . . . . . . . . . .  13
       7.1.1.  Identifier  . . . . . . . . . . . . . . . . . . . . .  13
       7.1.2.  Name  . . . . . . . . . . . . . . . . . . . . . . . .  13
       7.1.3.  URI . . . . . . . . . . . . . . . . . . . . . . . . .  17
       7.1.4.  Description . . . . . . . . . . . . . . . . . . . . .  17
       7.1.5.  Reference . . . . . . . . . . . . . . . . . . . . . .  17
       7.1.6.  Change Controller . . . . . . . . . . . . . . . . . .  17
       7.1.7.  Version (of Registry Format)  . . . . . . . . . . . .  18
     7.2.  Metric Definition Category  . . . . . . . . . . . . . . .  18
       7.2.1.  Reference Definition  . . . . . . . . . . . . . . . .  18
       7.2.2.  Fixed Parameters  . . . . . . . . . . . . . . . . . .  18
     7.3.  Method of Measurement Category  . . . . . . . . . . . . .  19
       7.3.1.  Reference Method  . . . . . . . . . . . . . . . . . .  19
       7.3.2.  Packet Stream Generation  . . . . . . . . . . . . . .  19
       7.3.3.  Traffic Filter  . . . . . . . . . . . . . . . . . . .  20
       7.3.4.  Sampling Distribution . . . . . . . . . . . . . . . .  20
       7.3.5.  Run-time  Runtime Parameters . . . . . . . . . . . . . . . . .  21
       7.3.6.  Role  . . . . . . . . . . . . . . . . . . . . . . . .  22
     7.4.  Output Category . . . . . . . . . . . . . . . . . . . . .  22
       7.4.1.  Type  . . . . . . . . . . . . . . . . . . . . . . . .  22
       7.4.2.  Reference Definition  . . . . . . . . . . . . . . . .  23
       7.4.3.  Metric Units  . . . . . . . . . . . . . . . . . . . .  23
       7.4.4.  Calibration . . . . . . . . . . . . . . . . . . . . .  23
     7.5.  Administrative information  . . . . . . . . . . . . . . .  24 Information
       7.5.1.  Status  . . . . . . . . . . . . . . . . . . . . . . .  24
       7.5.2.  Requester . . . . . . . . . . . . . . . . . . . . . .  24
       7.5.3.  Revision  . . . . . . . . . . . . . . . . . . . . . .  24
       7.5.4.  Revision Date . . . . . . . . . . . . . . . . . . . .  24
     7.6.  Comments and Remarks  . . . . . . . . . . . . . . . . . .  24
   8.  Processes for Managing the Performance Metric Metrics Registry Group   24
     8.1.  Adding new New Performance Metrics to the Performance Metrics
           Registry  . . . . . . . . . . . . . . . . . . . . . . . .  25
     8.2.  Revising Registered Performance Metrics . . . . . . . . .  26
     8.3.  Deprecating Registered Performance Metrics  . . . . . . .  28
   9.  Security considerations . . . . . . . . . . . . . . . . . . .  28 Considerations
   10. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  29
     10.1.  Registry Group . . . . . . . . . . . . . . . . . . . . .  29
     10.2.  Performance Metric Metrics Name Elements . . . . . . . . . . . .  29
     10.3.  New Performance Metrics Registry . . . . . . . . . . . .  30
   11. Blank Registry Template . . . . . . . . . . . . . . . . . . .  32
     11.1.  Summary  . . . . . . . . . . . . . . . . . . . . . . . .  32
       11.1.1.  ID (Identifier)  . . . . . . . . . . . . . . . . . .  32
       11.1.2.  Name . . . . . . . . . . . . . . . . . . . . . . . .  32
       11.1.3.  URI  . . . . . . . . . . . . . . . . . . . . . . . .  32
       11.1.4.  Description  . . . . . . . . . . . . . . . . . . . .  32
       11.1.5.  Reference
       11.1.6.  Change Controller  . . . . . . . . . . . . . . . . .  32
       11.1.6.
       11.1.7.  Version (of Registry Format) . . . . . . . . . . . .  32
     11.2.  Metric Definition  . . . . . . . . . . . . . . . . . . .  32
       11.2.1.  Reference Definition . . . . . . . . . . . . . . . .  32
       11.2.2.  Fixed Parameters . . . . . . . . . . . . . . . . . .  32
     11.3.  Method of Measurement  . . . . . . . . . . . . . . . . .  33
       11.3.1.  Reference Method . . . . . . . . . . . . . . . . . .  33
       11.3.2.  Packet Stream Generation . . . . . . . . . . . . . .  33
       11.3.3.  Traffic Filtering (observation) (Observation) Details  . . . . . .  33
       11.3.4.  Sampling Distribution  . . . . . . . . . . . . . . .  33
       11.3.5.  Run-time  Runtime Parameters and Data Format  . . . . . . . .  33
       11.3.6.  Roles  . . . . . . . . . . . . . . . . . . . . . . .  33
     11.4.  Output . . . . . . . . . . . . . . . . . . . . . . . . .  33
       11.4.1.  Type . . . . . . . . . . . . . . . . . . . . . . . .  34
       11.4.2.  Reference Definition . . . . . . . . . . . . . . . .  34
       11.4.3.  Metric Units . . . . . . . . . . . . . . . . . . . .  34
       11.4.4.  Calibration  . . . . . . . . . . . . . . . . . . . .  34
     11.5.  Administrative items . . . . . . . . . . . . . . . . . .  34 Items
       11.5.1.  Status . . . . . . . . . . . . . . . . . . . . . . .  34
       11.5.2.  Requester  . . . . . . . . . . . . . . . . . . . . .  34
       11.5.3.  Revision . . . . . . . . . . . . . . . . . . . . . .  34
       11.5.4.  Revision Date  . . . . . . . . . . . . . . . . . . .  34
     11.6.  Comments and Remarks . . . . . . . . . . . . . . . . . .  34
   12. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  34
   13. References  . . . . . . . . . . . . . . . . . . . . . . . . .  35
     13.1.
     12.1.  Normative References . . . . . . . . . . . . . . . . . .  35
     13.2.
     12.2.  Informative References . . . . . . . . . . . . . . . . .  36
   Acknowledgments
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  37

1.  Introduction

   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
   [RFC6390] specifies guidelines for their development.

   The definition and use of Performance Metrics in the IETF has have been
   fostered in various working groups (WG), most (WGs).  Most notably:

   *  The "IP Performance Metrics" (IPPM) WG is the WG primarily
      focusing on Performance Metrics definition at the IETF.

   *  The "Benchmarking Methodology" WG (BMWG) defines many Performance
      Metrics for use in laboratory benchmarking of inter-networking internetworking
      technologies.

   *  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)"
      [RFC3611], 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"
      [RFC3550].

   *  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.

   *  The "Performance Metrics for Other Layers" (PMOL) a concluded WG (concluded)
      defined some Performance Metrics related to Session Initiation
      Protocol (SIP) voice quality [RFC6035].

   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. application specific.

   Despite the importance of Performance Metrics, there are two related
   problems for the industry. industry:

   *  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, discovering which Performance Metrics have been specified,
      to avoid developing a new Performance Metric that is very similar, similar
      but not quite inter-operable. interoperable.

   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 Performance Metrics
   Registry maintained by the IANA.

   This (IANA).  As
   such, this document requests that defines the new IANA create and maintain a Performance Metrics Registry, according to
   Registry.

   Per this document, IANA has created and 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.

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   Performance Metric:  A Performance Metric is 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 [RFC2330] and broader than the
      definition of performance metric a Performance Metric in [RFC6390].

   Registered Performance Metric:  A Registered Performance Metric is 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.
      Registry.

   Performance Metrics Registry:  The IANA registry Registry containing
      Registered Performance Metrics.

   Proprietary Registry:  A set of metrics that are registered in a
      proprietary registry, Registry, as opposed to the Performance Metrics
      Registry.

   Performance Metrics Experts:  The Performance Metrics Experts is a  A group of designated experts [RFC8126]
      selected by the IESG to validate the Performance Metrics before
      updating the Performance Metrics Registry.  The Performance
      Metrics Experts work closely with IANA.

   Parameter:  A Parameter is an  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.

      |  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. complimentary
      |  probability: delivery ratio.

   Active Measurement Method: Methods:  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 Section 3.4 of[RFC7799]. of [RFC7799].  Examples of Active
      Measurement Methods are the measurement methods Measurement Methods for the One way one-way
      delay metric defined in [RFC7679] and the one for round trip round-trip delay metric
      defined in [RFC2681].

   Passive Measurement Method: Methods:  Methods of Measurement conducted on
      network traffic, generated by either from (1) the end users or from
      (2) 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 Section 3.6 of [RFC7799].  One
      characteristic of Passive Measurement Methods is that sensitive
      information may be observed, and observed and, as a consequence, stored in the
      measurement system.

   Hybrid Measurement Method:  Hybrid Methods are Methods:  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 knowledge and observations of the stream of interest.
      The complete definition of Hybrid Methods is specified in section
      Section 3.8 of [RFC7799].

3.  Scope

   This document is intended for two different audiences:

   1.  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).

   2.  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.

   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.

   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 [RFC6248].  Finally, this
   document gives a set of guidelines for requesters and expert
   reviewers Expert
   Reviewers of candidate Registered Performance Metrics.

   This document makes no attempt to populate

   [RFC8912] populates the Performance Metrics new Registry with initial entries; the related memo
   [I-D.ietf-ippm-initial-registry] proposes the initial set of regsitry entries.

4.  Motivation  Motivations for a the Performance Metrics Registry

   In this section, we detail several motivations for the Performance
   Metrics Registry.

4.1.  Interoperability

   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):

   o

   Control protocol:  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 [RFC7594].  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.

   o

   Report protocol:  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.

   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) registries defined by other organizations or (2) private ones.
   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.

4.2.  Single point Point of reference Reference for Performance Metrics

   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.

4.3.  Side benefits Benefits

   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 [RFC6576] examines whether the results produced by
   independent implementations are equivalent in the context of
   evaluating the completeness and clarity of metric specifications.
   This
   [RFC6576] is another BCP [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 be noted, with a reference to the test
   results.

5.  Criteria for Performance Metrics Registration

   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 be:

   1.  interpretable  Interpretable by the user.

   2.  implementable  Implementable by the software or hardware designer, designer.

   3.  deployable  Deployable by network operators, operators.

   4.  accurate  Accurate in terms of producing equivalent results, and for
       interoperability and deployment across vendors, vendors.

   5.  Operationally useful, so that it has significant industry
       interest and/or has seen deployment, deployment.

   6.  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.

   In essence, there needs to be evidence that (1) a candidate
   Registered Performance Metric has significant industry interest, interest or
   has seen
   deployment, deployment and (2) there is agreement that the candidate
   Registered Performance Metric serves its intended purpose.

6.  Performance Metric Metrics Registry: Prior attempt Attempt

   There was a previous attempt to define a metric registry RFC 4148 Metrics Registry [RFC4148].
   However, it was obsoleted by RFC 6248 [RFC6248] because it was "found to be
   insufficiently detailed to uniquely identify IPPM metrics... [there
   was too much] variability possible when characterizing a metric exactly"
   exactly", which led to the RFC4148 registry IPPM Metrics Registry defined in [RFC4148]
   having "very few users, if any".

   A couple of any."

   Three interesting additional quotes from RFC 6248 [RFC6248] might help to
   understand the issues related to that registry.

   1.  "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."

   2.  "The current registry structure has been found to be
       insufficiently detailed to uniquely identify IPPM metrics."

   3.  "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."

   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.

6.1.  Why this This Attempt Should Succeed

   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), Section 5) and imposes a
   group of Performance Metrics Experts that will provide guidelines to
   assess if a Performance Metric is properly specified.

   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.  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- 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
   (Section 13 of RFC 2330 [RFC2330]) allows implementation to be ambiguous.

7.  Definition of the Performance Metric Metrics Registry

   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 be populated with the "NA" "N/A" value (Non (Not Applicable).  However,
   the "NA" "N/A" value MUST NOT 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 give general guidelines for populating the new
   column(s) for existing entries.

   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.

   Each column serves as a check-list checklist item and helps to avoid omissions
   during registration and expert review.

=======================================================================
Legend: Expert Review [RFC8126].

   Registry Categories and Columns are shown below as: in this format:

       Category
       ------------------...
       Column |  Column |...
=======================================================================

   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
   --------------------

   There is a blank template of the Registry template provided in
   Section 11 of this memo.

7.1.  Summary Category

7.1.1.  Identifier

   A

   This entry provides a numeric identifier Identifier for the Registered
   Performance Metric.  This
   identifier Identifier MUST be unique within the
   Performance Metrics Registry.

   The Registered Performance Metric unique identifier Identifier is an unbounded
   integer (range 0 to infinity).

   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.

   When adding newly new Registered Performance Metrics to the Performance
   Metrics Registry, IANA SHOULD 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 inform IANA of this decision.

7.1.2.  Name

   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.

   Names are composed of the following elements, separated by an
   underscore character "_":

      MetricType_Method_SubTypeMethod_... Spec_Units_Output

   o

   MetricType: a  A combination of the directional properties and the
      metric measured, such as and not limited to:

         RTDelay (Round Trip Delay)

         RTDNS (Response

      RTDelay:  Round-Trip Delay

      RTDNS:  Response Time Domain Name Service)

         RLDNS (Response Service

      RLDNS:  Response Loss Domain Name Service)

         OWDelay (One Way Delay)
         RTLoss (Round Trip Service

      OWDelay:  One-Way Delay

      RTLoss:  Round-Trip Loss)

         OWLoss (One Way

      OWLoss:  One-Way Loss)

         OWPDV (One Way

      OWPDV:  One-Way Packet Delay Variation)

         OWIPDV (One Way

      OWIPDV:  One-Way Inter-Packet Delay Variation)

         OWReorder (One Way Variation

      OWReorder:  One-Way Packet Reordering)

         OWDuplic (One Way Reordering

      OWDuplic:  One-Way Packet Duplication)

         OWBTC (One Way Duplication

      OWBTC:  One-Way Bulk Transport Capacity)

         OWMBM (One Way Model Based Metric)

         SPMonitor (Single Point Monitor)

         MPMonitor (Multi-Point Capacity

      OWMBM:  One-Way Model-Based Metric

      SPMonitor:  Single-Point Monitor

      MPMonitor:  Multi-Point Monitor)

   o

   Method:  One of the methods defined in [RFC7799], such as and not
      limited to:

         Active (depends

      Active:  depends on a dedicated measurement packet stream and
         observations of the stream)

         Passive (depends

      Passive:  depends *solely* on observation of one or more existing
         packet streams)

         HybridType1 (observations streams

      HybridType1:  Hybrid Type I observations on one stream that
         combine both
         active Active Methods and passive methods)

         HybridType2 (observations Passive Methods as described in
         [RFC7799])

      HybridType2:  Hybrid Type II observations on two or more streams
         that combine both active Active Methods and passive methods)

         Spatial (Spatial Metric of RFC5644)

   o Passive Methods as
         described in [RFC7799])

      Spatial:  spatial metric as described in [RFC5644])

      SubTypeMethod:  One or more sub-types subtypes to further describe the
         features of the entry, such as and not limited to:

         ICMP (Internet

         ICMP:  Internet Control Message Protocol)

         IP (Internet

         IP:  Internet Protocol)

         DSCPxx (where

         DSCPxx:  where xx is replaced by a Diffserv code point)

         UDP (User

         UDP:  User Datagram Protocol)
         TCP (Transport

         TCP:  Transport Control Protocol)

         QUIC:  QUIC (QUIC transport protocol)

         HS (Hand-Shake,

         HS:  Hand-Shake, such as TCP's 3-way HS)

         Poisson (Packet

         Poisson:  packet generation using Poisson distribution)

         Periodic (Periodic

         Periodic:  periodic packet generation)

         SendOnRcv (Sender

         SendOnRcv:  sender keeps one packet in-transit in transit by sending when
            previous packet arrives)

         PayloadxxxxB (where

         PayloadxxxxB:  where xxxx is replaced by an integer, the number
            of octets or 8-bit Bytes in the Payload))

         SustainedBurst (Capacity Payload)

         SustainedBurst:  capacity test, worst case)

         StandingQueue (test

         StandingQueue:  test of bottleneck queue behavior)

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

   o

         Spec:  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., [RFC7679] 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 be proposed and reviewed for
            consistency and uniqueness by the Expert Reviewer.

   o

         Units:  The units of measurement for the output, such as and
            not limited to:

            Seconds

         Ratio (unitless)
         Percent (value

            Ratio:  unitless

            Percent:  value multiplied by 100%)

         Logical (1 100%

            Logical:  1 or 0) 0

            Packets

         BPS (Bits

            BPS:  bits per Second)

         PPS (Packets second

            PPS:  packets per Second)

         EventTotal (for unit-less counts)

         Multiple (more second

            EventTotal:  for unitless counts

            Multiple:  more than one type of unit)

         Enumerated (a unit

            Enumerated:  a list of outcomes) outcomes

            Unitless

   o

         Output:  The type of output resulting from measurement, such as
            and not limited to:

            Singleton

         Raw (multiple Singletons)

            Raw:  multiple singletons

            Count

            Minimum

            Maximum

            Median

            Mean

         95Percentile (95th Percentile)

         99Percentile (99th Percentile)

         StdDev (Standard Deviation)

            95Percentile:  95th percentile

            99Percentile:  99th percentile

            StdDev:  standard deviation

            Variance

         PFI (Pass, Fail, Inconclusive)

         FlowRecords (descriptions

            PFI:  pass, fail, inconclusive

            FlowRecords:  descriptions of flows observed)

         LossRatio (lost observed

            LossRatio:  lost packets to total packets, <=1) <=1

   An example is:

   RTDelay_Active_IP-UDP-Periodic_RFCXXXXsecY_Seconds_95Percentile example, as described in section Section 4 of [I-D.ietf-ippm-initial-registry]. [RFC8912], is

      RTDelay_Active_IP-UDP-Periodic_RFC8912sec4_Seconds_95Percentile

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

7.1.3.  URI

   The URIs URI column MUST contain a URL [RFC3986] 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 human-
   readable information for one registry entry. Registry Entry.  The URL SHALL 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 <https://www.iana.org/>.  Section 4
   of [RFC8912], as well as subsequent major sections of
   [I-D.ietf-ippm-initial-registry] that document,
   provide an example of a target file in HTML form (sections 4 and higher). form.

7.1.4.  Description

   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.

7.1.5.  Reference

   This entry gives the specification containing the candidate registry
   entry which Registry
   Entry that was reviewed and agreed, agreed upon, if such an RFC or other
   specification exists.

7.1.6.  Change Controller

   This entry names the entity responsible for approving revisions to
   the registry entry, Registry Entry and SHALL provide contact information (for an
   individual, where appropriate).

7.1.7.  Version (of Registry Format)

   This entry gives the version number for the registry Registry format used.
   Formats complying with this memo MUST use 1.0.  The version number
   SHALL NOT change unless a new RFC is published that changes the
   registry
   Registry format.  The version number of registry entries Registry Entries SHALL NOT
   change unless the registry entry Registry Entry is updated (following the procedures
   in
   section Section 8).

7.2.  Metric Definition Category

   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. Performance Metric.

7.2.1.  Reference Definition

   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.

7.2.2.  Fixed Parameters

   Fixed Parameters are Parameters whose value values must be specified in the
   Performance Metrics Registry.  The measurement system uses these
   values.

   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 [RFC2330], 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 [RFC3550].  Varying
   MIN_SEQUENTIAL values can alter the loss report report, and this value variable
   could be set as a Fixed Parameter.

   Parameters MUST 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 appear in this column (or Run-time the Runtime Parameters column).

   Parameters MUST have a well-specified data format.

   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. Entry.

7.3.  Method of Measurement Category

   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.

7.3.1.  Reference Method

   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.

   Specifically, this section should include pointers to pseudocode or
   actual code that could be used for an unambiguous implementation.

7.3.2.  Packet Stream Generation

   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.

   Each entry for this column contains the following information:

   o

   Value:  The name of the packet stream scheduling discipline

   o

   Reference: the  The specification where the parameters Parameters of the stream are
      defined

   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.

   The simplest example of stream specification is Singleton singleton scheduling
   (see [RFC2330]), 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) Poisson, distributed as described in [RFC2330] and Periodic (2) periodic,
   as described in [RFC3432].  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.

7.3.3.  Traffic Filter

   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,
   values/ranges, such as address ranges, and flow or session identifiers.
   Identifiers.

   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) [RFC5475]
   Property Match
   Filtering Filtering, which reuses IPFIX [RFC7012].  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.

   The traffic filter Traffic Filter includes the following information:

   Type: the  The type of traffic filter Traffic Filter used, e.g. e.g., BPF, PSAMP, OpenFlow
      rule, etc. etc., as defined by a normative reference

   Value: the  The actual set of rules expressed

7.3.4.  Sampling Distribution

   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:

   Value: the  The name of the sampling distribution

   Reference definition: pointer  Pointer to the specification where the
      sampling distribution is properly defined. defined

   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.

   Sampling

   PSAMP is documented in "Sampling and Filtering Techniques for IP
   Packet Selection are
   documented in the PSAMP (Packet Sampling) Selection" [RFC5475], while the "A Framework for Packet Selection
   and Reporting, Reporting" [RFC5474] 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, [RFC5477], Exports"
   [RFC5477] and the Flow process provided in "Flow Selection Techniques, Techniques"
   [RFC7014].

7.3.5.  Run-time  Runtime Parameters

   Run-Time

   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).

   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.

   Parameters MUST 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 appear in
   this column.

   A Data Format data format for each Run-time Runtime Parameter MUST 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-address" as defined in [RFC6991].  The actual encoding(s) used
   must be explicitly defined for each Run-time parameter. Runtime Parameter.  IPv6
   addresses and options MUST be accommodated, allowing Registered
   Performance Metrics to be used in that address family.  Other address
   families are permissable. permissible.

   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. Measurement.

7.3.6.  Role

   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").

   When the Role column of a registry entry Registry Entry defines more than one Role,
   then
   the Role SHALL be treated as a Run-time Runtime Parameter and supplied for
   execution.  It should be noted that the LMAP framework [RFC7594]
   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[RFC8194]. Runtime Parameters.

7.4.  Output Category

   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.

   Some metrics embed one specific statistic in the reference metric
   definition, while others allow several output types or statistics.

7.4.1.  Type

   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
   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 Section 7.1.2 above for a list of Output Types.
   output types.

7.4.2.  Reference Definition

   This column contains a pointer to the specification(s) where the
   output type and format are defined.

7.4.3.  Metric Units

   The measured results must be expressed using some standard dimension
   or units of measure.  This column provides the units.

   When a sample of singletons (see Section 11 of[RFC2330] of [RFC2330] for
   definitions of these terms) is collected, this entry will specify the
   units for each measured value.

7.4.4.  Calibration

   Some specifications for Methods of Measurement include the
   possibility ability to
   perform an error calibration.  Section 3.7.3 of [RFC7679] 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 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.

   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).

   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.

7.5.  Administrative information Information

7.5.1.  Status

   The

   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.

7.5.2.  Requester

   The

   This entry indicates the requester for the Registered Performance
   Metric.  The requester MAY be a document, such document (such as RFC, an RFC) or a
   person.

7.5.3.  Revision

   The

   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.

7.5.4.  Revision Date

   The

   This entry indicates the date of acceptance or of the most recent
   revision for the Registered Performance Metric.  The date SHALL be
   determined by IANA and the reviewing Performance Metrics Expert.

7.6.  Comments and Remarks

   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.

8.  Processes for Managing the Performance Metric Metrics Registry Group

   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 Section 7
   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.

   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.

8.1.  Adding new New Performance Metrics to the Performance Metrics Registry

   Requests to add Registered Performance Metrics in the Performance
   Metrics Registry SHALL 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 [RFC8126] policy [RFC8126] 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,
   so that the submission formatting will benefit from the normal IETF Internet Draft
   Internet-Draft submission processing (including HTML-ization). HTMLization).

   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).

   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 criteria listed in
   Section 5 criteria have not been met, then the proposed Performance Metrics
   Registry entry Entry MUST be removed from the text.  Once evidence exists
   that the Performance Metric meets the criteria in section Section 5, the
   proposed Performance Metrics Registry entry Entry SHOULD be submitted to
   IANA to be evaluated in consultation with the Performance Metric Metrics
   Experts for registration at that time.

   Authors of proposed Registered Performance Metrics SHOULD review
   compliance with the specifications in this document to check their
   submissions before sending them to IANA.

   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 coordinate with the
   requester to change the request to be compliant, otherwise so that it is compliant; otherwise,
   IANA SHALL coordinate resolution of issues on behalf of the expert.
   The Performance Metric Metrics Experts MAY choose to reject clearly
   frivolous or inappropriate change requests outright, but such
   exceptional circumstances should be rare.

   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.

   Decisions by the Performance Metric Metrics Experts may be appealed as in per
   Section 7 10 of [RFC8126].

8.2.  Revising Registered Performance Metrics

   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).

   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'. 'Deprecated'.

   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.

   Revisions are initiated by sending a candidate Registered Performance
   Metric definition to IANA, as in per Section 8.1, identifying the existing
   Performance Metrics Registry entry, Entry, and explaining how and why the
   existing entry should be revised.

   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
   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.

   A change to a Registered Performance Metric SHALL be determined to be
   backward-compatible
   backward compatible when:

   1.  it involves the correction of an error that is obviously only
       editorial;
       editorial, or

   2.  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; defined,
       or

   3.  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);
       value), or

   4.  it harmonizes with an external reference that was itself
       corrected.

   If a Performance Metric revision is deemed permissible and backward- backward
   compatible by the Performance Metric Metrics Experts, according to the rules
   in this document, IANA SHOULD 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, Name, SHALL remain unchanged
   (even
   even when the change is the result of IETF Standards Action; the Action.  The
   revised registry entry Registry Entry SHOULD 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). column.

   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.

   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.

   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.

   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 Status field,
   which SHALL be changed to "Deprecated". 'Deprecated'.

8.3.  Deprecating Registered Performance Metrics

   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 be deprecated and
   replaced when:

   1.  the Registered Performance Metric definition has an error or
       shortcoming that cannot be permissibly changed as in per Section 8.2
       Revising
       ("Revising Registered Performance Metrics; Metrics"), or

   2.  the deprecation harmonizes with an external reference that was
       itself deprecated through that reference's accepted deprecation
       method.

   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.

   The revision number of a Registered Performance Metric is incremented
   upon deprecation, and the revision Revision Date is updated, as with any
   revision.

   The intentional use of deprecated Registered Performance Metrics
   should result in a log entry or human-readable warning by the
   respective application.

   Names and Metric IDs of deprecated Registered Performance Metrics
   must not be reused.

   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"). 'Deprecated').

9.  Security considerations Considerations

   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.

   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.

10.  IANA Considerations

   With the background and processes described in earlier sections, this
   document requests the following IANA Actions.

   Editor's Note: Mock-ups of the implementation of this set of requests
   have been prepared with IANA's help during development of this memo,
   and have been captured in
   has taken the Proceedings of IPPM working group
   sessions. following IANA is currently preparing a mock-up.  A recent version
   is available here: http://encrypted.net/IETFMetricsRegistry-106.html actions.

10.1.  Registry Group

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

   Registration Procedure: Specification Required

   Reference: <This RFC> RFC 8911

   Experts: Performance Metrics Experts

   Note: TBD

   Note that this applies to all of the Registries in the Performance
   Metrics Group.

10.2.  Performance Metric Metrics Name Elements

   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:

      MetricType:

      Method:

      SubTypeMethod:

      Spec:

      Units:

      Output:

   will
   Registries.  IANA has created the the following registries, which
   contain the current set of possibilities for Performance Metrics
   Registry Entry Names. names.

      Metric Type

      Method

      SubTypeMethod

      Spec

      Units

      Output

   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.  The Name Elements in each registry Registry
   are case-sensitive. case sensitive.

   When preparing a Metric entry Entry for Registration, registration, the developer SHOULD
   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.

   A candidate Metric Entry RFC or an immutable document for 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) Name Element(s)
   would be reviewed along with the metric entry. 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)
   [RFC8126], 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).

10.3.  New Performance Metrics Registry

   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:

      Identifier:

      Name:

      URI:

      Description:

      Reference:

      Identifier

      Name

      URI

      Description

      Reference

      Change Controller:

      Version: Controller

      Version

   Descriptions of these columns and additional information found in the
   template for registry entries Registry Entries (categories and columns) are further
   defined in section Section 7.

   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 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 inform IANA of this decision.

   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 Section 7.

   The "URI" URI column will have a URL to the full template of each
   registry entry. Registry
   Entry.  The Registry Entry text SHALL 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.

   The "Reference" Reference column will include an RFC number, an approved
   specification designator from another standards body, or some other
   immutable document.

   New assignments for the Performance Metrics Summary Registry will be
   administered by IANA through the Specification Required policty policy
   [RFC8126] (which includes Expert
   Review) [RFC8126], 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.

   Extensions of to the Performance Metrics Summary Registry require IETF
   Standards Action.  Only one form of registry Registry extension is envisaged:

   1.

   *  Adding columns, or both categories and columns, to accommodate
      unanticipated aspects of new measurements and metric categories.

   If the Performance Metrics Summary Registry is extended in this way,
   the
   Version version number of future entries complying with the extension
   SHALL be incremented (either in (in either the unit or the tenths digit,
   depending on the degree of extension. extension).

11.  Blank Registry Template

   This section provides a blank template to help IANA and registry
   entry Registry
   Entry writers.

11.1.  Summary

   This category includes multiple indexes to the registry entry: Registry Entry: the
   element ID and metric name. Metric Name.

11.1.1.  ID (Identifier)

   <insert a numeric identifier, Identifier, an integer, TBD>

11.1.2.  Name

   <insert name the Name, according to the metric naming convention>

11.1.3.  URI

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

11.1.4.  Description

   <provide a description>

11.1.5.  Reference

   <provide the RFC or other specification that contains the approved
   candidate Registry Entry>

11.1.6.  Change Controller

11.1.6.

   <provide information regarding the entity responsible for approving
   revisions to the Registry Entry (including contact information for an
   individual, where appropriate)>

11.1.7.  Version (of Registry Format)

11.2.  Metric Definition

   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. "Fixed
   Parameters".

11.2.1.  Reference Definition

   <Full

   <provide a full bibliographic reference to an immutable doc.>

   <specific document>

   <provide a specific section reference and additional clarifications,
   if needed>

11.2.2.  Fixed Parameters

   <list and specify Fixed Parameters, input factors that must be
   determined and embedded in the measurement system for use when
   needed>

11.3.  Method of Measurement

   This category includes columns for references to relevant sections of
   the immutable documents(s) document(s) and any supplemental information needed to
   ensure an unambiguous methods method for implementations.

11.3.1.  Reference Method

   <for the metric, insert relevant section references and supplemental
   info>

11.3.2.  Packet Stream Generation

   <list

   <provide a list of generation parameters Parameters and section/spec references
   if needed>

11.3.3.  Traffic Filtering (observation) (Observation) Details

   The

   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).

   <section reference>.

   <provide a section reference>

11.3.4.  Sampling Distribution

   <insert time distribution details, or how this is diff different from the
   filter>

11.3.5.  Run-time  Runtime Parameters and Data Format

   Run-time

   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.

   <list

   <provide a list of run-time parameters, Runtime Parameters and their data formats>

11.3.6.  Roles

   <lists

   <list the names of the different roles from the measurement method> Measurement Method>

11.4.  Output

   This category specifies all details of the Output output of measurements
   using the metric.

11.4.1.  Type

   <insert the name of the output type, type -- raw results or a selected
   summary statistic>

11.4.2.  Reference Definition

   <describe the reference data format for each type of result>

11.4.3.  Metric Units

   <insert units for the measured results, and provide the reference
   specification>.
   specification>

11.4.4.  Calibration

   <insert information on calibration>

11.5.  Administrative items Items

   This category provides administrative information.

11.5.1.  Status

   <current

   <provide status: 'Current' or deprecated> 'Deprecated'>

11.5.2.  Requester

   <name or RFC,

   <provide a person's name, an RFC number, etc.>

11.5.3.  Revision

   <1.0>

   <provide the revision number: 1.0>

11.5.4.  Revision Date

   <format YYYY-MM-DD>

   <provide the date, in YYYY-MM-DD format>

11.6.  Comments and Remarks

   <Additional (Informational)

   <list any additional (informational) details for this entry>

12.  Acknowledgments

   Thanks to Brian Trammell and Bill Cerveny, IPPM chairs, for leading
   some brainstorming sessions on this topic.  Thanks to Barbara Stark
   and Juergen Schoenwaelder for the detailed feedback and suggestions.
   Thanks to Andrew McGregor for suggestions on metric naming.  Thanks
   to Michelle Cotton for her early IANA review, and to Amanda Barber
   for answering questions related to the presentation of the registry
   and accessibility of the complete template via URL.  Thanks to Roni
   Even for his review and suggestions to generalize the procedures.
   Thanks to ~all the Area Directors for their reviews.

13.  References

13.1.

12.1.  Normative References

   [RFC2026]  Bradner, S., "The Internet Standards Process -- Revision
              3", BCP 9, RFC 2026, DOI 10.17487/RFC2026, October 1996,
              <https://www.rfc-editor.org/info/rfc2026>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC2330]  Paxson, V., Almes, G., Mahdavi, J., and M. Mathis,
              "Framework for IP Performance Metrics", RFC 2330,
              DOI 10.17487/RFC2330, May 1998,
              <https://www.rfc-editor.org/info/rfc2330>.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, DOI 10.17487/RFC3986, January 2005,
              <https://www.rfc-editor.org/info/rfc3986>.

   [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>.

   [RFC6390]  Clark, A. and B. Claise, "Guidelines for Considering New
              Performance Metric Development", BCP 170, RFC 6390,
              DOI 10.17487/RFC6390, October 2011,
              <https://www.rfc-editor.org/info/rfc6390>.

   [RFC6576]  Geib, R., Ed., Morton, A., Fardid, R., and A. Steinmitz,
              "IP Performance Metrics (IPPM) Standard Advancement
              Testing", BCP 176, RFC 6576, DOI 10.17487/RFC6576, March
              2012, <https://www.rfc-editor.org/info/rfc6576>.

   [RFC7799]  Morton, A., "Active and Passive Metrics and Methods (with
              Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799,
              May 2016, <https://www.rfc-editor.org/info/rfc7799>.

   [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <https://www.rfc-editor.org/info/rfc8126>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

13.2.

12.2.  Informative References

   [I-D.ietf-ippm-initial-registry]
              Morton, A., Bagnulo, M., Eardley, P., and K. D'Souza,
              "Initial Performance Metrics Registry Entries", draft-
              ietf-ippm-initial-registry-15 (work in progress), December
              2019.

   [RFC2681]  Almes, G., Kalidindi, S., and M. Zekauskas, "A Round-trip
              Delay Metric for IPPM", RFC 2681, DOI 10.17487/RFC2681,
              September 1999, <https://www.rfc-editor.org/info/rfc2681>.

   [RFC3432]  Raisanen, V., Grotefeld, G., and A. Morton, "Network
              performance measurement with periodic streams", RFC 3432,
              DOI 10.17487/RFC3432, November 2002,
              <https://www.rfc-editor.org/info/rfc3432>.

   [RFC3550]  Schulzrinne, H., Casner, S., Frederick, R., and V.
              Jacobson, "RTP: A Transport Protocol for Real-Time
              Applications", STD 64, RFC 3550, DOI 10.17487/RFC3550,
              July 2003, <https://www.rfc-editor.org/info/rfc3550>.

   [RFC3611]  Friedman, T., Ed., Caceres, R., Ed., and A. Clark, Ed.,
              "RTP Control Protocol Extended Reports (RTCP XR)",
              RFC 3611, DOI 10.17487/RFC3611, November 2003,
              <https://www.rfc-editor.org/info/rfc3611>.

   [RFC4148]  Stephan, E., "IP Performance Metrics (IPPM) Metrics
              Registry", BCP 108, RFC 4148, DOI 10.17487/RFC4148, August
              2005, <https://www.rfc-editor.org/info/rfc4148>.

   [RFC5474]  Duffield, N., Ed., Chiou, D., Claise, B., Greenberg, A.,
              Grossglauser, M., and J. Rexford, "A Framework for Packet
              Selection and Reporting", RFC 5474, DOI 10.17487/RFC5474,
              March 2009, <https://www.rfc-editor.org/info/rfc5474>.

   [RFC5475]  Zseby, T., Molina, M., Duffield, N., Niccolini, S., and F.
              Raspall, "Sampling and Filtering Techniques for IP Packet
              Selection", RFC 5475, DOI 10.17487/RFC5475, March 2009,
              <https://www.rfc-editor.org/info/rfc5475>.

   [RFC5477]  Dietz, T., Claise, B., Aitken, P., Dressler, F., and G.
              Carle, "Information Model for Packet Sampling Exports",
              RFC 5477, DOI 10.17487/RFC5477, March 2009,
              <https://www.rfc-editor.org/info/rfc5477>.

   [RFC6035]  Pendleton, A., Clark, A., Johnston, A., and H. Sinnreich,
              "Session Initiation Protocol Event Package for Voice
              Quality Reporting", RFC 6035, DOI 10.17487/RFC6035,
              November 2010, <https://www.rfc-editor.org/info/rfc6035>.

   [RFC6248]  Morton, A., "RFC 4148 and the IP Performance Metrics
              (IPPM) Registry of Metrics Are Obsolete", RFC 6248,
              DOI 10.17487/RFC6248, April 2011,
              <https://www.rfc-editor.org/info/rfc6248>.

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6991, DOI 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/info/rfc6991>.

   [RFC7012]  Claise, B., Ed. and B. Trammell, Ed., "Information Model
              for IP Flow Information Export (IPFIX)", RFC 7012,
              DOI 10.17487/RFC7012, September 2013,
              <https://www.rfc-editor.org/info/rfc7012>.

   [RFC7014]  D'Antonio, S., Zseby, T., Henke, C., and L. Peluso, "Flow
              Selection Techniques", RFC 7014, DOI 10.17487/RFC7014,
              September 2013, <https://www.rfc-editor.org/info/rfc7014>.

   [RFC7594]  Eardley, P., Morton, A., Bagnulo, M., Burbridge, T.,
              Aitken, P., and A. Akhter, "A Framework for Large-Scale
              Measurement of Broadband Performance (LMAP)", RFC 7594,
              DOI 10.17487/RFC7594, September 2015,
              <https://www.rfc-editor.org/info/rfc7594>.

   [RFC7679]  Almes, G., Kalidindi, S., Zekauskas, M., and A. Morton,
              Ed., "A One-Way Delay Metric for IP Performance Metrics
              (IPPM)", STD 81, RFC 7679, DOI 10.17487/RFC7679, January
              2016, <https://www.rfc-editor.org/info/rfc7679>.

   [RFC8194]  Schoenwaelder, J.

   [RFC8912]  Morton, A., Bagnulo, M., Eardley, P., and V. Bajpai, "A YANG Data Model for
              LMAP Measurement Agents", K. D'Souza,
              "Initial Performance Metrics Registry Entries", RFC 8194, 8912,
              DOI 10.17487/RFC8194,
              August 2017, <https://www.rfc-editor.org/info/rfc8194>. 10.17487/RFC8912, September 2020,
              <https://www.rfc-editor.org/info/rfc8912>.

Acknowledgments

   Thanks to Brian Trammell and Bill Cerveny, IPPM chairs, for leading
   some brainstorming sessions on this topic.  Thanks to Barbara Stark
   and Juergen Schoenwaelder for the detailed feedback and suggestions.
   Thanks to Andrew McGregor for suggestions on metric naming.  Thanks
   to Michelle Cotton for her early IANA review, and to Amanda Baber for
   answering questions related to the presentation of the Registry and
   accessibility of the complete template via URL.  Thanks to Roni Even
   for his review and suggestions to generalize the procedures.  Thanks
   to all of the Area Directors for their reviews.

Authors' Addresses

   Marcelo Bagnulo
   Universidad Carlos III de Madrid
   Av. Universidad 30
   Leganes, Madrid
   28911
   SPAIN Leganes Madrid
   Spain

   Phone: 34 91 6249500
   Email: marcelo@it.uc3m.es
   URI:   http://www.it.uc3m.es

   Benoit Claise
   Cisco Systems, Inc.
   De Kleetlaan 6a b1
   1831 Diegem
   Belgium

   Email: bclaise@cisco.com

   Philip Eardley
   BT
   Adastral Park, Martlesham Heath
   Ipswich
   ENGLAND
   United Kingdom

   Email: philip.eardley@bt.com

   Al Morton
   AT&T Labs
   200 Laurel Avenue South
   Middletown, NJ
   USA 07748
   United States of America

   Email: acmorton@att.com

   Aamer Akhter
   Consultant
   118 Timber Hitch
   Cary, NC
   USA
   United States of America

   Email: aakhter@gmail.com