16 Oct
2007
16 Oct
'07
7:09 p.m.
Iñaki Baz Castillo wrote:
...
Remember: OpenSer is not dialog aware (except using "dialog" module, but
it's
not the purpose).
OpenSer is just transactions aware. In a simple dialog there are at least
those transactions:
- INVITE (from caller to called) and responses 100, 180, 200.
- ACK (from caller to called)
- BYT (from caller to called) and response 200.
All these 3 transactions becomes a dialog JUST in the endpoints (phones), but
for OpenSer they are completely INDEPENDENT transactions.
I recomend you study it a lot since it's vital:
http://www.switzernet.com/people/emin-gabrielyan/070410-SIP-transactions/
http://4z.com/people/emin-gabrielyan/public/070412-SIP-record-route/
Indeed, another website to consider is tech-invite.com. E.g.
http://tech-invite.com/Ti-sip-dialog.html
explains what a SIP dialog is and shows how such a dialog is created and
terminated.
And if you think this is complicated, have a look at
http://tech-invite.com/Ti-ims-sesflow-1.html ;-)
/Christian