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UDP Checksum Complement in the One-Way Active Measurement Protocol (OWAMP) and Two-Way Active Measurement Protocol (TWAMP)
RFC 7820

Approval announcement
Draft of message to be sent after approval:


From: The IESG <>
To: "IETF-Announce" <>
Cc:,,,,, "The IESG" <>,
Subject: Document Action: 'UDP Checksum Complement in OWAMP and TWAMP' to Experimental RFC (draft-ietf-ippm-checksum-trailer-06.txt)

The IESG has approved the following document:
- 'UDP Checksum Complement in OWAMP and TWAMP'
  (draft-ietf-ippm-checksum-trailer-06.txt) as Experimental RFC

This document is the product of the IP Performance Metrics Working Group.

The IESG contact persons are Spencer Dawkins and Martin Stiemerling.

A URL of this Internet Draft is:

Ballot Text

Technical Summary

In many IP measurement protocols, timestamps are required to calculate
packet transfer delay, and these timestamps occupy fields above the IP
layer. When implementers prefer to avoid the delay of stack processing,
it is preferred to insert the timestamps as close to the network 
interface as possible, but this also requires maintaining sanity 
among checksums and other integrity checks.  This memo defines one way
to assign an optional field at the end of the UDP payload of test packets
to complement the timestamp and populate that field to keep checksum accuracy.

Working Group Summary

There has been sufficient review during 2 years of development,
and the comments were both constructive and supportive of this simple idea.
The draft can serve a useful purpose for the industry.

Document Quality

One chip vendor has implemented the procedure in the draft from a hardware
perspective, and another chip vendor has indicated their plans (privately)
to do the same.  There are no known HW and SW implementations with TWAMP or
OWAMP at this time.

As far as expert reviews, there was sufficient review from the community
of TWAMP experts.


Al Morton is Shepherd, Spencer Dawkins is AD.

RFC Editor Note