Subject: A question on compound RTCP packets

From: Colin Perkins <[email-masked]>
Date: Thu, 12 Aug 1999 17:49:35 +0100

Rereading draft-ietf-avt-rtp-new-04, I notice that (in section 6.1):

   ...all RTCP packets MUST be sent in a compound packet of at least
   two individual packets, with the following format RECOMMENDED:
   ...
        SR or RR:  The first RTCP packet in the compound packet MUST
             always be a report packet to facilitate header validation
             as described in Appendix A.2. This is true even if no data
             has been sent nor received, in which case an empty RR MUST
             be sent, and even if the only other RTCP packet in the
             compound packet is a BYE.
   ...
        SDES:  An SDES packet containing a CNAME item MUST be included
             in each compound RTCP packet. Other source description
             items MAY optionally be included if required by a
             particular application, subject to bandwidth constraints
             (see Section 6.3.9).

It would seem that this is inconsistent, since the word RECOMMENDED allows
for other formats in exceptional circumstances, yet the later use of MUST 
disallows that. 

The options seem to be either to change the MUSTs to SHOULD, or to change
the word RECOMMENDED to REQUIRED (or just remove the RECOMMENDED). I'd
recommend to latter. 

Comments?

Colin

---

From: Henning Schulzrinne <[email-masked]>
Date: Mon, 16 Aug 1999 19:57:29 -0400

> the word RECOMMENDED to REQUIRED (or just remove the RECOMMENDED). I'd

There being no objections, I removed the word RECOMMENDED from the first
sentence.

-- 
Henning Schulzrinne   http://www.cs.columbia.edu/~hgs