Subject: WG Review: IP Performance Metrics (ippm)

From: The IESG <[email-masked]>
Date: Tue, 05 Feb 2002 12:51:08 -0500

A revised charter has been received for the IP Performance Metrics (ippm)
in the Transport Services Area. The IESG has not yet made a decision, and
the following is sibmitted for informational purposes only.

Description of Working Group

The IPPM WG will develop a set of standard metrics that can be applied
to the quality, performance, and reliability of Internet data delivery
services. These metrics will be designed such that they can be
performed by network operators, end users, or independent testing
groups. It is important that the metrics not represent a value
judgment (i.e. define "good" and "bad"), but rather provide unbiased
quantitative measures of performance.

Functions peripheral to Internet data delivery services, such as
NOC/NIC services, are beyond the scope of this working group.

The IPPM WG will produce documents that define specific metrics and
procedures for accurately measuring and documenting these metrics.
The metrics are:
  - connectivity
  - one-way delay and loss
  - round-trip delay and loss
  - delay variation
  - loss patterns
  - packet reordering
  - bulk transport capacity
  - link bandwidth capacity
This is the cumulative set, including the metricsalready completed
and published.

The working group will closely review and then be guided by an
IESG document on how metrics advance along the standards track within
the IETF.  This document will also be relevant to the work of the
benchmarking working group (BMWG).  The first draft of this document
was discussed at IETF 51.
Additionally, the WG will produce Proposed Standard AS documents,
comparable to applicability statements in RFC 2026, that will
focus on procedures for measuring the individual metrics and how these
metrics characterize features that are important to different service
classes, such as bulk transport, periodic streams, or multimedia
streams. It is specifically out of scope for this working group to
actually characterize traffic, for example to characterize a
voice-over-IP stream. Each AS document will discuss the performance
characteristics that are pertinent to a specified service class;
clearly identify the set of metrics that aid in the description of
those characteristics; specify the methodologies required to collect
said metrics; and lastly, present the requirements for the common,
unambiguous reporting of testing results. Specific topics of these
AS documents must be approved by the Area Directors as charter
additions.

The WG will produce a protocol to enable communication among test
equipment that implements the one-way metrics. The intent is to create
a protocol that provides a base level of functionality that will allow
different manufacturer's equipment that implements the metrics
according to a standard to interoperate. A protocol requirements
document will guide the protocol design.

The WG will also produce a MIB to retrieve the results of IPPM
metrics, such as one-way delay and loss, to facilitate the
communication of metrics to existing network management systems. Thus,
the group will create a MIB that contains predominantly read only
variables.  If, after the protocol requirements document is finished,
the group decides that it is appropriate to add variables that control
the underlying measurements that the metrics report, such a control
structure may be added as a separate document, subject to review by
the IESG.

The intent of the WG is to cooperate with other appropriate standards
bodies and forums (such as T1A1.3, ITU-T SG 12 and SG 13) to promote
consistent approaches and metrics. Within the IETF process, IPPM
metrics definitions will be subject to as rigorous a scrutiny for
usefulness, clarity, and accuracy as other protocol standards. The
IPPM WG will interact with other areas of IETF activity whose scope
intersect with the requirement of these specific metrics. These
include working groups such as BMWG, RMONMIB, and TEWG.