Paul,
From my interop experience, I seem to remember that many (most?) EPs simply
do not populate the audio, video, or data components of perCallInfo. This, IMO, makes perCallInfo useless. It's been awhile, so maybe more EPs are providing this info now. Regardless, we shouldn't rely on just an assumption and should therefore require that these fields accurately reflect the current mode.
Paul Long ipDialog, Inc.
-----Original Message----- From: Mailing list for parties associated with ITU-T Study Group 16 [mailto:ITU-SG16@echo.jf.INTEL.COM]On Behalf Of Paul E. Jones Sent: Sunday, December 23, 2001 7:14 PM To: ITU-SG16@echo.jf.INTEL.COM Subject: Re: Including RTCP report packets in IRR
Paul,
I suppose this is probably in need of clarification, but the assumption was that if the call contained an audio session, the audio element would be included. Likewise for video, etc. Unfortunately, there are a few fields in H.225.0 that are labeled as "OPTIONAL" in the ASN.1, so implementers assume that semantically they're optional, but that's not the case. We don't want to change the syntax (since we don't want to mandate the inclusion of a field when the call doesn't have a session of that type), so I suppose it would be nice to see a proposal for clarification of this issue.
One other thought about the RTCP stats is that we report them in the DRQ rather than the IRR. One problem with IRRs is that if they are sent too frequently, an extremely busy system can get bogged down processing those messages. I imagine that you'd want to set the IRR timer somewhere outside the length of an average call. Doing so, though, would mean you never get stats for the average call. So perhaps DRQ alone (or in addition to) the IRR is the right approach.
Paul
----- Original Message ----- From: "Paul Long" plong@IPDIALOG.COM To: ITU-SG16@echo.jf.INTEL.COM Sent: Tuesday, December 18, 2001 10:42 AM Subject: Re: Including RTCP report packets in IRR
Paul,
Please note though that an EP is not required to include any media info in perCallInfo, i.e., audio, video, and data. I imagine that this was an oversight, but we ought to explicitly require v5+ EPs to report all currently active media sessions, including RTP.
Paul Long ipDialog, Inc.