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Network Time Protocol Version 4 (NTPv4) Extension Fields

The information below is for an old version of the document.
Document Type This is an older version of an Internet-Draft whose latest revision is Expired
Authors Tal Mizrahi , Danny Mayer , Harlan Stenn
Last updated 2017-05-17 (Latest revision 2016-11-13)
Stream (None)
Expired & archived
Stream Stream state (No stream defined)
Consensus boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Expired
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


Network Time Protocol version 4 (NTPv4) defines the optional usage of extension fields. An extension field, as defined in RFC 5905 [RFC5905], resides after the end of the NTP header, and supplies optional capabilities or information that is not conveyed in the standard NTP header. This document updates RFC 5905 [RFC5905] by clarifying some points regarding NTP extension fields and their usage with legacy Message Authentication Codes (MACs). With the adoption of this update, the authors recommend rescinding [Err3627].


Tal Mizrahi
Danny Mayer
Harlan Stenn

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)