[Freeswitch-users] SRTP in PhonerLite and Freeswitch

Brian West brian at freeswitch.org
Wed Apr 23 12:07:46 PDT 2008

Can you forward me the full invite coming in from the phone and I can  
tell you why... what It feels like is they are doing crypto lines in  
the RTP/AVP instead of RTP/SAVP as per the RFC says.


On Apr 23, 2008, at 2:01 PM, Krzysiek wrote:

> Hi
> I have 2 softphones PhonerLite (they support SRTP via SDES ) and the  
> freeswitch (windows RC1 version) server and I wanted to make secure  
> call between those two endpoints (SRTP).
> I spend whole day on testing this scenario and my conclusions are:
> - when the option: <action application="export"  
> data="sip_secure_media=true"/> is uncommented, and both enpoints  
> have enabled SRTP then:
> 1) Initiator of the session sends SIP Invite with a=crypto paramter  
> and supported codecs
> 2) Freeswitch receives SIP Invite and sends SIP Invite to the  
> receiver (also with the crypto)
> 3) Receiver receives the SIP Invite with the a=crypto parameter and  
> he sends back supported codecs with 200 OK message (but without  
> a=crypto parametr. Is that ok? I'm afraid not)
> 4) Freeswitch sends 200 OK message but witout any codecs: m=audio 0  
> RTP/AVP 19 and no a= parameters!
> 5) Final result is that the second leg of the session between  
> Freeswitch and receiver has SRTP transport enbaled and the first leg  
> (initiator- Freeswitch) doesn't hear anything - no codecs! However  
> Freeswitch is sending RTP (not SRTP) pacekets to the initiator.
> Could someone explain to me, what is going on, and why freeswitch  
> doesn't forward codecs accepted by the receiver to the initiator?
> Is it a PhonerLite's bug or freeswitch's? Maybe someone has tested  
> SRTP with the PhonerLite softphone or any other free softphone with  
> srtp support?
> When I uncommented: <param name="Inbound-no-media" value="true">
> everything works fine. The parameter <action application="export"  
> data="sip_secure_media=true"/> doesn't change anything then (but i  
> cound miss something).
> Thanks for help
> Chris
> _______________________________________________
> Freeswitch-users mailing list
> Freeswitch-users at lists.freeswitch.org
> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
> http://www.freeswitch.org

Brian West
sip:brian at freeswitch.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20080423/e40ebf72/attachment-0002.html 

More information about the FreeSWITCH-users mailing list