Last Call Review of draft-ietf-avtcore-6222bis-03
review-ietf-avtcore-6222bis-03-genart-lc-holmberg-2013-06-12-00

Request Review of draft-ietf-avtcore-6222bis
Requested rev. no specific revision (document currently at 06)
Type Last Call Review
Team General Area Review Team (Gen-ART) (genart)
Deadline 2013-06-11
Requested 2013-05-30
Draft last updated 2013-06-12
Completed reviews Genart Last Call review of -03 by Christer Holmberg (diff)
Secdir Last Call review of -03 by Magnus Nystrom (diff)
Assignment Reviewer Christer Holmberg
State Completed
Review review-ietf-avtcore-6222bis-03-genart-lc-holmberg-2013-06-12
Reviewed rev. 03 (document currently at 06)
Review result Ready
Review completed: 2013-06-12

Review
review-ietf-avtcore-6222bis-03-genart-lc-holmberg-2013-06-12






I am the assigned Gen-ART reviewer for this draft. For background on Gen-ART, please see the FAQ at <http://wiki.tools.ietf.org/area/gen/trac/wiki/GenArtfaq>




 




Document:                         draft-ietf-avtcore-6222bis-03




 




Reviewer:                           Christer Holmberg




 




Review Date:                     10 June 2013




 




IETF LC End Date:             11 June 2013




 




IETF Telechat Date:         N/A




 




Summary:  There is a minor issue, described below, that I think should be clarified before the document is published.




 




Major Issues: None




 




Minor Issues:




 




Section 4.1 says:




 




   “The RTCP CNAME can be either persistent across different RTP sessions




   for an RTP endpoint or unique per session, meaning that an RTP




   endpoint chooses a different RTCP CNAME for each RTP session.”




 




…and:




 




   “An RTP endpoint that is emitting multiple related RTP streams that




   require synchronization at the other endpoint(s) MUST use the same




   RTCP CNAME for all streams that are to be synchronized.  This




   requires a short-term persistent RTCP CNAME that is common across




   several RTP streams, and potentially across several related RTP




   sessions.  A common example of such use occurs when lip-syncing audio




   and video streams in a multimedia session, where a single participant




   has to use the same RTCP CNAME for its audio RTP session and for its




   video RTP session.  Another example might be to synchronize the




   layers of a layered audio codec, where the same RTCP CNAME has to be




   used for each layer.”




 




…etc.




 




The text talks about the CNAME being unique within an RTP session, or to span over multiple RTP sessions, but it seems to omit that, *

within

* an RTP session, you can also use *

different

* CNAME values, if e.g. there is no
 synchronization requirement between the RTP streams.




 




 




Editorial nits: None




 




Best regards,




 




Christer