Re: [sipcore] Reviewers needed for new music-on-hold technique

"Elwell, John" <> Thu, 18 August 2011 07:04 UTC

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From: "Elwell, John" <>
To: "Worley, Dale R (Dale)" <>, "" <>
Date: Thu, 18 Aug 2011 09:05:04 +0200
Thread-Topic: Reviewers needed for new music-on-hold technique
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Subject: Re: [sipcore] Reviewers needed for new music-on-hold technique
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Yes, it does now make an appropriate mention of RTCP - thanks.

I am also curious as to why there are a couple of mentions of using directionality "inactive". Why would any of the entities involved use "inactive" unless they don't wish to send/receive music-on-hold? In particular, why would the INVITE from the executing UA to the MOH source use "inactive" - it is specifically asking the MOH source to send music, so if it wants "inactive", why send the INVITE?

Perhaps this is to do with multiple media, where the remote UA offers several media, and MOH is required only for one of these, so the other media descriptions are set to "inactive" in the INVITE to the MOH source. Whether or not that was the intention of "inactive", I think further discussion of multi-media situations is required. For example, if the remote UA offers audio and video and the executing UA wants MOH only for audio, how would it behave? Perhaps the example should be extended to show such a possibility.


> -----Original Message-----
> From: Worley, Dale R (Dale) [] 
> Sent: 17 August 2011 21:06
> To:; Elwell, John
> Subject: Reviewers needed for new music-on-hold technique
> > From: Elwell, John [john.elwell at]
> > 
> > I haven't reviewed it in detail, but I see there is no mention of
> > RTCP. Perhaps it isn't really relevant, except that it provides
> > another reason why the media server needs to supply an IP 
> address and
> > port - even though it will not receive RTP, it will receive 
> RTCP. The
> > RTCP port could be implicit or explicit.
> I don't think I've mentioned this, but draft-worley-service-example-06
> has updates to point out that allowing RTCP is useful.  See
> and
> search for "RTCP".  These changes are carried forward into the
> current -07 draft as well.
> Do these changes suffice?
> Dale