RFC 3262, "Reliability of Provisional Responses in Session Initiation Protocol (SIP)", June 2002

Errata ID: 4601
Status: Verified
Type: Technical
Publication Format(s) : TEXT
Reported By: Christer Holmberg
Date Reported: 2016-01-25
Verifier Name: Ben Campbell
Date Verified: 2016-01-25

Section 4 says:

If a provisional response is received for an initial request, and
that response contains a Require header field containing the option
tag 100rel, the response is to be sent reliably.  If the response is
a 100 (Trying) (as opposed to 101 to 199), this option tag MUST be
ignored, and the procedures below MUST NOT be used.

It should say:

If a provisional response is received for an initial request, and
that response contains a Require header field containing the option
tag 100rel, the response was sent by the UAS reliably.  If the
response is a 100 (Trying) (as opposed to 101 to 199), this option
tag MUST be ignored, and the procedures below MUST NOT be used.

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