[Freeswitch-dev] Strange behaviour in SOFIA SIP

[Visciano Giovanni]

Preconditions on sip profile
----------------------------
inbound-codec-prefs NOT set
outbound-codec-prefs NOT set
inbound-proxy-media=TRUE
inbound-bypass-media=FALSE
inbound-late-negotiation=TRUE + inherit_codec=TRUE

TEST scenario
-------------
SIP phone send INVITE with SDP to FS

INVITE
SDP[codelist=PCMA, PCMU, G722, G729] --> FS

FS has just the CORE_PC_MODULE [PCMA, PCMU, PASS-THR, VIDEO-PASS-THR, L16]

The "ep_codec_string" channel variable is loaded with [PCMA, PCMU]

EXPECTED
--------
In "proxy-media + late-negotiation" scenario: ep_codec_string=[PCMA,PCMU,G722,G729]

PROBLEM
-------
According to the documentation (http://wiki.freeswitch.org/wiki/Codec_negotiation):

"ep_codec_string: This variable is only available if late negotiation is enabled on the profile. It's a readable string containing all the codecs proposed by the calling endpoint."
and
"inherit_codec=true (only applicable when late-negotiation is enabled) will take the codec negotiated when the B leg answers and pass it to the A leg so it also uses the same codec (if the A leg supports it); otherwise, it will use whatever it can from its own list"

The variable ep_codec_string doesn't contain ALL the codecs proposed by the calling endpoint. It contains the intersection between the codecs proposed by the calling and the codecs loaded in FS.
In proxy-media / no-media configuration the called endpoint doesn't have the calling codec list so he can't negotiate using all the capabilities available.
(I'm working on a test endpoint module that should work in proxy and no-media configuration ... mod_sofia vs mod_sofia works because they look at the remote sdp variable)

Source reference - sofia_glue.c->sofia_glue_set_r_sdp_codec_string()


Regards,
Giovanni


Internet Email Confidentiality Footer
-----------------------------------------------------------------------------------------------------
La presente comunicazione, con le informazioni in essa contenute e ogni documento o file allegato, e' rivolta unicamente alla/e persona/e cui e' indirizzata ed alle altre da questa autorizzata/e a riceverla. Se non siete i destinatari/autorizzati siete avvisati che qualsiasi azione, copia, comunicazione, divulgazione o simili basate sul contenuto di tali informazioni e' vietata e potrebbe essere contro la legge (art. 616 C.P., D.Lgs n. 196/2003 Codice in materia di protezione dei dati personali). Se avete ricevuto questa comunicazione per errore, vi preghiamo di darne immediata notizia al mittente e di distruggere il messaggio originale e ogni file allegato senza farne copia alcuna o riprodurne in alcun modo il contenuto. 

This e-mail and its attachments are intended for the addressee(s) only and are confidential and/or may contain legally privileged information. If you have received this message by mistake or are not one of the addressees above, you may take no action based on it, and you may not copy or show it to anyone; please reply to this e-mail and point out the error which has occurred. 
-----------------------------------------------------------------------------------------------------

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-dev/attachments/20111020/f6b3731f/attachment-0001.html