Hi All, I have two questions on the open source PJSIP. I greatly appreciate if someone could clarify the same. 1. NAT issue. I recently experienced an issue with voice path on iOS. I analyzed the issue and found that PJSIP does not translate the IP addresses in the SDP though it translates the IP addresses (from Private to Public) in the signaling contact and via headers. Due to this incomplete translation, the RTP exchange fails and results in media failure. As a workaround, I had to modify the default values of the following 2 parameters so that PJSIP does not perform any translations and leaves it to the ALG (we use INGATE firewall) to do the translations. This fixes the voice path issue acc_cfg.allow_contact_rewrite = PJ_FALSE; acc_cfg.allow_via_rewrite = PJ_FALSE; The only concern I have with the above change is that all NATs may not have ALG functionality, and the voice path may still fail. Hence, please let me know is there any reason why PJSIP doesn't translate the IP addresses in the SDP? Is there any setting or configurables or values I need to modify on PJSIP to make the calls (media) working across NATs 2. SIP REFER and transport=tcp parameter in the Refer-To header My PJSIP transport is set to TCP and it succesfully registers on TCP. However when it receives an incoming SIP REFER (like transfer) over TCP, PJSIP tries to send the event notifications (indicating the progress of the call (sipfrag)) over UDP. Since the UDP transport is not initialized the outgoing NOTIFY fails resulting in the failure to make a new call. With reference to the same, I have the following questions. a. Why does not PJSIP send NOTIFY on the configured transport (TCP in this case)? Why does it try to send it over UDP? b. If the above is acceptable, Kindly let me know the RFC/Section that states that NOTIFY can also be sent over UDP. c. Why does PJSIP rely on transport=tcp parameter in the incoming Refer-To header of the REFER message to send the NOTIFY over TCP? Thanks & Best Regards, Srinivas The only concern -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20130318/2fa1b396/attachment-0001.html>
