[OpenSER-Users] proper call tear down

Hi, This is probably more SIP related than openSER, but I'll ask it here anyway When we were at VON I brought up the subject of accounting and verifying proper call tear down, and it seems the ideal solution from a sip perspective is RFC 4028 (SIP session timers) which tracks the actual sip session with the UA. What I'm starting to realize is that support for this is very limited and I haven't found much evidence if any in the devices where network failures are most likely to occur ATAs and end user devices. This seems to leave me relying on the media stream, but this also has its issues with network issues occurring when calls are placed on hold. Does anyone have any good suggestions for accurate accounting when dealing with end users, or is what I described as good as I'm going to get, until I find some solutions that support 4028? Cheers Miles Scruggs Wide Ideas | Operations | miles.scruggs(a)wideideas.com | 509.525.6522 ext 4880