RFC 4330, "Simple Network Time Protocol (SNTP) Version 4 for IPv4, IPv6 and OSI", January 2006

Note: This RFC has been obsoleted by RFC 5905

Errata ID: 2263
Status: Verified
Type: Technical
Publication Format(s) : TEXT
Reported By: Scott Barnes
Date Reported: 2010-05-15
Verifier Name: Nevil Brownlee
Date Verified: 2013-05-23

Section 5 says:

4.  The server reply should be discarded if any of the LI, Stratum,
    or Transmit Timestamp fields is 0 or the Mode field is not 4
    (unicast) or 5 (broadcast).

It should say:

4.  The server reply should be discarded if any of the VN, Stratum, 
    or Transmit Timestamp fields is 0 or the Mode field is not 4 
    (unicast) or 5 (broadcast).

Notes:

Zero is a legal value for the LI field under normal conditions. Zero is not legal for VN field, however.

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