Guidelines for Defining Packet Timestamps

Approval announcement
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From: The IESG <>
To: IETF-Announce <>
Cc:,,,,, Karen O'Donoghue <>, The IESG <>,
Subject: Document Action: 'Guidelines for Defining Packet Timestamps' to Informational RFC (draft-ietf-ntp-packet-timestamps-09.txt)

The IESG has approved the following document:
- 'Guidelines for Defining Packet Timestamps'
  (draft-ietf-ntp-packet-timestamps-09.txt) as Informational RFC

This document is the product of the Network Time Protocol Working Group.

The IESG contact persons are √Čric Vyncke and Suresh Krishnan.

A URL of this Internet Draft is:

Technical Summary

Various network protocols make use of binary-encoded timestamps that are incorporated in the protocol packet format, referred to as packet timestamps for short.  This document specifies guidelines for defining packet timestamp formats in networking protocols at various layers.  It also presents three recommended timestamp formats.  The target audience of this memo includes network protocol designers.  It is expected that a new network protocol that requires a packet timestamp will, in most cases, use one of the recommended timestamp formats.  If none of the recommended formats fits the protocol    requirements, the new protocol specification should specify the format of the packet timestamp according to the guidelines in this document.

The rationale behind defining a relatively small set of recommended formats is that it enables significant reuse; network protocols can typically reuse the timestamp format of the Network Time Protocol (NTP) or the Precision Time Protocol (PTP), allowing a straightforward integration with an NTP or a PTP-based timer. Moreover, since accurate timestamping mechanisms are often implemented in hardware, a new network protocol that reuses an existing timestamp format can be quickly deployed using existing hardware timestamping capabilities. 

Working Group Summary

The document has clear working group consensus for publication, and has been reviewed by several WG participants since its initial adoption as a working group item. 

Document Quality

This document has been reviewed and revised several times during its development. There were no specific external expert reviews conducted. 

Karen O'Donoghue is acting as the Document Shepherd.  Suresh Krishnan is the Responsible Area Director.