Hi,

next question: I receive the following SDP from a device (FritzBox 7170)):

m=audio 7078 RTP/AVP 8 0 2 102 100 99 97 101.
a=rtpmap:2 G726-32/8000.
a=rtpmap:102 G726-32/8000.
a=rtpmap:100 G726-40/8000.
a=rtpmap:99 G726-24/8000.
a=rtpmap:97 iLBC/8000.
a=fmtp:97 mode=30.
a=rtpmap:101 telephone-event/8000

(=> Note: No a= lines for PCMA/PCMU, should not be necessary)

I've set in my sbc-profile the following:

sdpfilter_list=g722,pcma,pcmu,g729,telephone-event

This produces the following on the other leg:

m=audio 7078 RTP/AVP 101.
a=rtpmap:101 telephone-event/8000

Surprisingly my Gateway cannot accept only DTMF-Calls... ;-)
Shouldn't the SBC keep G711a/u in the codec list? The codecs are
"standard codecs" according to RFC1890, so it should not be necessary
to describe them further.
Is there a "nice" way to fix this? Otherwise i will dig into the code
and see what i can do....

Carsten

2011/8/8 Carsten Bock <[email protected]>:
> Hi,
>
> thanks for the advice. I will take a look at the code.
> I know, that " a=silenceSupp:off - - - -" is correct to the standards,
> i've just seen some buggy gateways which omitted the "- - - -" and
> made some Cisco-Gateways fail....
>
> Carsten
>
> 2011/8/4 Stefan Sayer <[email protected]>:
>> Hi,
>>
>> o Carsten Bock on 08/04/2011 12:22 PM:
>>>
>>> Hi,
>>>
>>> short question:
>>> In the codecfilter.sbcprofile.conf-Example it says the following:
>>>
>>> # sdp_filter can be transparent,whitelist or blacklist
>>> # - leave empty (commented) for no touching SDP
>>> # - transparent does SDP reconstruction ('sanity check')
>>> # - whitelist and blacklist filter codec on both sides
>>>
>>> If set to transparent or whitelisting, is the SDP really
>>> re-constructed? I've noticed, that the session-name (s=) is passed
>>> through as well as the "o="-lines.
>>
>> yes, it is 'reconstructed', which means parsed by the SDP parser and then
>> rebuilt by SDP generator. The parser takes over both s and o SDP attributes.
>>
>>> What about other attributes? I wonder, if a gateway sends me buggy
>>> "a=silenceSupp:off - - - -" lines, is it passed through as well? I
>>> know some Cisco-Gateways will not connect that call, if the
>>> "a=silenceSupp:off" is incorrect according to the standards.
>>
>> hm, isn't this line:
>>  a=silenceSupp:off - - - -
>> correct according to RFC3108?
>>
>> just fyi, if this needs to be sanitized in a way, the code would need to go
>> into SDPFilter.cpp (checking media.attributes).
>>
>>> By the way: Is there an easy way to add a "own" music-on-hold
>>> announcement, if a call through the SBC is put on hold?
>>
>> no, not yet.
>>
>> Stefan
>>
>>>
>>> Thanks,
>>> Carsten
>>>
>>> v=0.
>>> o=root 2018628531 2018628531 IN IP4 46.252.21.133.
>>> s=sipgate VoIP GW.
>>> c=IN IP4 46.252.21.133.
>>> t=0 0.
>>> m=audio 30218 RTP/AVP 8 0 3 127.
>>> a=rtpmap:8 PCMA/8000.
>>> a=rtpmap:0 PCMU/8000.
>>> a=rtpmap:3 GSM/8000.
>>> a=rtpmap:127 telephone-event/8000.
>>> a=fmtp:127 0-16.
>>> a=silenceSupp:off - - - -.
>>> a=ptime:20.
>>> a=sendrecv.
>>> a=nortpproxy:yes.
>>>
>>>
>>
>>
>> --
>> frafos.com
>>
>
>
>
> --
> Carsten Bock
> http://www.ng-voice.com
> mailto:[email protected]
>
> Schomburgstr. 80
> 22767 Hamburg
> Germany
>
> Mobile +49 179 2021244
> Office +49 40 34927219
> Fax +49 40 34927220
>
> ~~~~~~~~~~~~~~~~~~~~
> Upcoming Events: "10 years of SER" in Berlin on September 2nd, 2011 (@
> Fraunhofer Institute, Berlin):
> http://sip-router.org/10-years-ser/
>



-- 
Carsten Bock
http://www.ng-voice.com
mailto:[email protected]

Schomburgstr. 80
22767 Hamburg
Germany

Mobile +49 179 2021244
Office +49 40 34927219
Fax +49 40 34927220

~~~~~~~~~~~~~~~~~~~~
Upcoming Events: "10 years of SER" in Berlin on September 2nd, 2011 (@
Fraunhofer Institute, Berlin):
http://sip-router.org/10-years-ser/
_______________________________________________
Sems mailing list
[email protected]
http://lists.iptel.org/mailman/listinfo/sems

Reply via email to