Performance Metrics for Other Layers (pmol)
|Name:||Performance Metrics for Other Layers|
|Area:||Operations and Management Area (ops)|
Al Morton <firstname.lastname@example.org>
Alan Clark <email@example.com>
The successful implementation and operation of IP based applications
often depends on some underlying performance measurement
infrastructure that helps service operators or network managers to
recognize when performance is unsatisfactory and identify problems
affecting service quality. Standardized performance metrics add the
desirable features of consistent implementation, interpretation, no
The IETF has two Working Groups dedicated to the development of
performance metrics however each has strict limitations in their
- The Benchmarking Methodology WG has addressed a range of networking
technologies and protocols in their long history (such as IEEE 802.3,
ATM, Frame Relay, and Routing Protocols), but the charter strictly
limits their Performance characterizations to the laboratory
- The IP Performance Metrics WG has the mandate to develop metrics
applicable to the performance of Internet data delivery, but it is
specifically prohibited from developing metrics that characterize
traffic (such as a VoIP stream).
The IETF also has current and completed activities related to the
reporting of application performance metrics (e.g. RAQMON and RTCP XR)
and is also actively involved in the development of reliable transport
protocols which would affect the relationship between IP performance
and application performance.
Thus there is a gap in the currently chartered coverage of IETF WGs:
development of performance metrics for IP-based protocols and
applications that operate over UDP, TCP, SCTP, DCCP, Forward Error
Correction (FEC) and other robust transport protocols, and that can be
used to characterize traffic on live networks.
The working group will focus on the completion of two RFCs:
1. A PMOL framework and guidelines memo that will describe the
necessary elements of performance metrics of protocols and
applications transported over IETF-specified protocols (such as the
formal definition, purpose, and units of measure) and the various
types of metrics that characterize traffic on live networks (such as
metrics derived from other metrics, possibly on lower layers). The
framework will also address the need to specify the intended audience
and the motivation for the performance metrics. There will also be
guidelines for a performance metric development process that includes
entry criteria for new proposals (how a proposal might be evaluated
for possible endorsement by a protocol development working group), and
how an successful proposal will be developed. Also, it is recognized
that there are applications and protocols that do not need to use this
framework and can make use of simpler specific methods for determining
2. A proof-of-concept RFC defining performance metrics for SIP, based
on draft-malas-performance-metrics. This memo would serve as an
example of the framework and the PMOL development process in the IETF.
Discussion of new work proposals is strongly discouraged under the
initial charter of the PMOL WG, except to advise a protocol
development WG when they are evaluating a new work proposal for
related performance metrics.
The Working Group will work closely with the RAI and APPS areas,
performing early review of the documents with the two areas and
inviting their particpation in the WGLC.
The PMOL WG will also be guided by a document describing how memos
defining performance metrics are intended to advance along the IETF
Standards track (draft-bradner-metricstest).
PMOL WG will take advantage of expertise and seek to avoid overlap
with other standards development organizations, such as ETSI STQ, ITU-
T SG 12, ATIS IIF, ATIS PRQC, and others.
Performance Metrics Draft to IESG Review for consideration as Proposed Standard
PMOL Framework and Guidelines Draft to IESG Review for consideration as BCP
Discuss rechartering of the WG for new PMOL metrics work or shut down