RFC 3264, "An Offer/Answer Model with Session Description Protocol (SDP)", June 2002

Note: This RFC has been updated by RFC 6157, RFC 8843, RFC 9143

Errata ID: 3818
Status: Verified
Type: Technical
Publication Format(s) : TEXT
Reported By: Jörgen Axell
Date Reported: 2013-12-02
Verifier Name: Gonzalo Camarillo
Date Verified: 2013-12-03

Section 4 says:

   The agent receiving the offer MAY generate an answer, or it MAY
   reject the offer.  The means for rejecting an offer are dependent on
   the higher layer protocol.  The offer/answer exchange is atomic; if
   the answer is rejected, the session reverts to the state prior to the
   offer (which may be absence of a session).

It should say:

   The agent receiving the offer MAY generate an answer, or it MAY
   reject the offer.  The means for rejecting an offer are dependent on
   the higher layer protocol.  The offer/answer exchange is atomic; if
   the offer is rejected, the session reverts to the state prior to the
   offer (which may be absence of a session).

Notes:

You can't reject an answer. When the answer is received the SDP negotiation is completed.

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