RFC 3168, "The Addition of Explicit Congestion Notification (ECN) to IP", September 2001

Note: This RFC has been updated by RFC 4301, RFC 6040, RFC 8311

Errata ID: 6494
Status: Rejected
Type: Technical
Publication Format(s) : TEXT
Reported By: Joe Touch
Date Reported: 2021-03-24
Rejected by: Martin Duke
Date Rejected: 2021-03-24

Section Header says:

Updates: 2474, 2401, 793 

It should say:

Updates: 2474, 2401, 793, 791

Notes:

This is the first standards-track RFC to assign the two unused bits of the IP TOS byte to ECN. Granted it was suggested in RFC2481, but that was experimental and unable to update RFC791 because it would create a downref.
--VERIFIER NOTES--
As several have pointed out on the list, 2474 itself updates 791, so someone following 791 through the tree of its updates will consider 3168.

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