Subject: [Sip] RFC 3261 bug in description of 487?

From: "Paul D.Smith" <[email-masked]>
Date: Wed, 28 Apr 2004 16:24:06 +0100

It seems that the description of a 487 response in RFC 3261 is incomplete.
Consider the following sections from RFC 3261.

21.4.25 487 Request Terminated

   The request was terminated by a BYE or CANCEL request.  This response
   is never returned for a CANCEL request itself.

This might be interpreted as meaning that a 487 should _only_ be sent if
a request has been terminated by a BYE or a CANCEL.  However this is
not consistent with other parts of RFC 3261, where a 487 is generated
without the involvement of either BYE or CANCEL.  One example of this
is section 13.3.1, reproduced here.

13.3.1 Processing of the INVITE

   The UAS core will receive INVITE requests from the transaction layer.
   It first performs the request processing procedures of Section 8.2,
   which are applied for both requests inside and outside of a dialog.

   Assuming these processing states are completed without generating a
   response, the UAS core performs the additional processing steps:

      1. If the request is an INVITE that contains an Expires header
         field, the UAS core sets a timer for the number of seconds
         indicated in the header field value.  When the timer fires, the
         invitation is considered to be expired.  If the invitation
         expires before the UAS has generated a final response, a 487
         (Request Terminated) response SHOULD be generated.

In the this case a 487 response is generated without the involvement of
either CANCEL or BYE.

Am I correct in believing that sections such as 13.3.1 are correct and
there is simply a bug in that section 21.4.25 is incomplete?

Regards,
Paul DS

Paul D Smith
Network Protocols Group 
Data Connection Ltd (DCL)
Tel: +44 20 8366 1177  Email: [email-masked] 
Fax: +44 20 8363 1039  Web:   http://www.dataconnection.com

_______________________________________________
Sip mailing list  https://www1.ietf.org/mailman/listinfo/sip
This list is for NEW development of the core SIP Protocol
Use [email-masked] for questions on current sip
Use [email-masked] for new developments on the application of sip