Hi, I've just now stated reading about CallWeaver project. My target is to 
join OpenSer with a SIP PBX and Asterisk makes it difficult to me because 
some issues. I'd like to know how Callweaver handles these issues so I list 
some questions. Thanks a lot for any explanation about them:



1)  Sip spiral:

Asterisk chan_sip doesn't allow SIP spiral (not a loop). This is:

- Asterisk calls a user of a SIP proxy.
- This SIP proxy has a forwarding for this user that correspond with a PSTN 
number, so the INVITE is URI modified and sent back to Asterisk (the PSTN 
gateway).
- Asterisk receives the same INVITE it sent before (same fromt and to tags and 
call-id, but different URI so NOT the same INVITE) and rejects it with "482 
Loop Detected".

This is a pain since it could be a really cool feature that Asterisk makes 
impossible.

There is a related bug and patch not accepted and updated to trunk version:
  http://bugs.digium.com/view.php?id=7403

Since Callweaver uses Sofia SIP I hope this stack understands "482" and accept 
SIP spiral. Does it?



2)  Native transfer and direct RTP:

Asterisk allows native transfer with options "t" and/or "T" in "Dial" command. 
This native transfer is done by DTMF and Asterisk remains in the media path 
in order to get those DTMF's even if "canreinvite=yes" for both callee and 
callee.

But using "dtmfmode=info" the DTMF goes as SIP INFO messages (not in the RTP) 
so there is no reason Asterisk to remain into the media path. Anyway Asterisk 
remains in it :(

Reported bug in Asterisk:
  http://bugs.digium.com/view.php?id=11172
  (I reported it today and it seems fixed now !!!)




3)  Multidomain support - Virtual hosts:

Asterisk support for multidomain is really limited, just by asignig context to 
incoming calls based on the domain, no more.

Is there more about it in CallWeaver?




4)  Support for SIP Session Timers:

Asterisk doesn't support it, so if a UAC crashes while being in-hold (not 
sending RTP) then Asterisk has no way to know it so the channel remains open 
(a pain for CDR).

Does Callweaver support SIP Session Timers?
  http://www.faqs.org/rfcs/rfc4028.html




5)  Support for outbound proxy in [general]:

Asterisk doesn't allow using a outbound proxy for ALL outgoing calls, just for 
peers. Does CallWeaver allow it?




6) Big vulnerability with native transfer:
  Explained here:
    http://bugs.digium.com/view.php?id=10198

Does Callweaver fix it?



Best regards.

 

-- 
Iñaki Baz Castillo
_______________________________________________
Callweaver-users mailing list
[email protected]
http://lists.callweaver.org/mailman/listinfo/callweaver-users

Reply via email to