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Andreas,<BR>
<BR>
On Fri, 2008-01-11 at 15:41 +0100, Andreas Granig wrote:
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<FONT COLOR="#000000">Let me clear this up. In some deployments billing relies on successful </FONT>
<FONT COLOR="#000000">re-INVITEs (with an interval of some minutes) rather than on RTP </FONT>
<FONT COLOR="#000000">timeouts (which may be detected within some seconds). </FONT>
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Right. That's the solution I like the most.<BR>
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<FONT COLOR="#000000">This works because </FONT>
<FONT COLOR="#000000">they are rather closed systems with UACs which support the Session Timer </FONT>
<FONT COLOR="#000000">standard. </FONT>
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Well, you only need 1 SIP endpoint in the chain supporting SST for this to work, but obviously if this one breaks, well, you loose it all <IMG SRC="cid:1200069285.10721.3.camel@anice.longphone.fr" ALIGN="middle" ALT=":-)" BORDER="0"><BR>
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<FONT COLOR="#000000">So if a BYE is lost for some reason, the call is torn down on </FONT>
<FONT COLOR="#000000">the next re-INVITE latest.</FONT>
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I know <IMG SRC="cid:1200069285.10721.3.camel@anice.longphone.fr" ALIGN="middle" ALT=":-)" BORDER="0"><BR>
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<FONT COLOR="#000000">> I'm really curious, could you give me a real-world example of an</FONT>
<FONT COLOR="#000000">> RTP-detection based soution providing sub-minute dead UA detection ? </FONT>
<FONT COLOR="#000000">No, sorry, since I also don't rely on RTP regarding the billing :)</FONT>
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Well, seems in the end we have the same approch <IMG SRC="cid:1200069285.10721.3.camel@anice.longphone.fr" ALIGN="middle" ALT=":)" BORDER="0"><BR>
<BR>
What was strange to me (and still is), is the fact that some people are using RTP detection with a few seconds threshold. This is insane in my environment, and really I don't see an environment where it would not be a huge penalty, for the reasons I've given before in this thread :<BR>
- you cannot use VAD<BR>
- you're stuck with RTP proxying<BR>
- users cannot cut the mike on their phone (with business subscribers, this is a clear no-go)<BR>
- it's not generic at all, aka, it does not work for SIP sessions that are not phone calls <BR>
(IM sessions, using something else than RTP, or just oneway RTP like message diffusion etc...)<BR>
<BR>
So I'm saying it again: using RTP detection is an UGLY HACK (when used alone).<BR>
On the other hand, RTP detection + ping when you detect the stream went down, so you can check <BR>
if the stream went down but the user is still in control, is a good idea. So RTP detection is interesting<BR>
when used AS A PART OF A MORE COMPLEX SCHEME, but NOT standing alone.<BR>
<BR>
What do you think ?<BR>
<BR>
Regards,<BR>
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<B><FONT SIZE="2"><FONT COLOR="#808080">Jérôme Martin </FONT></FONT></B><B><FONT SIZE="2"><FONT COLOR="#bebebe">| </FONT></FONT></B><B><FONT SIZE="2"><FONT COLOR="#99cc00">LongPhone</FONT></FONT></B><BR>
<B><FONT SIZE="2"><FONT COLOR="#808080">Responsable Architecture Réseau</FONT></FONT></B><BR>
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<FONT COLOR="#c0c0c0">Mail :</FONT><FONT COLOR="#99cc00"> </FONT><FONT COLOR="#99cc00"><B><FONT SIZE="2">jmartin</FONT></B></FONT><FONT SIZE="2"><FONT COLOR="#bebebe">@longphone.fr</FONT></FONT><BR>
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