Hi all, I have a few question regarding how Pjsip and Pjsua goes about deciding what port to send it's packets to. Using Wireshark I've noticed the following in setting up a connection between Pjsua (with --rtp-port set to 5004) and some other SIP implementation; 1. The call is set up without any SIP server, and both parties describe that they will be sending to port 5004 (in the SDP). 2. Pjsua is sending it's packets to the receivers port 5004 as described in in the SDP setup & the other SIP implementation sends it's packets to port 5004 of the Pjsua. Here it should be noted that the other SIP implementation's source port is xxxx. 3. The other SIP implementation sends a few ICMP saying that port 5004 is unreachable. 4. Pjsua suddenly without any previous SDP message changes it's destination port to xxxx. During the whole session the audio going from the other SIP implementation to Pjsua is fine. The other SIP implementation never receives audio as it is awaiting audio on port 5004, but all output from the Pjsua is going to xxxx. So my questions are; A. Does Pjsua switch its destination port to xxxx because of the ICMP's or is this switch done because Pjsua always wants to send it's packets to the source of the received packets, which would be needed going through NAT's? B. If this is how Pjsua smartly tries going through NAT's. Does there exist a setting for Pjsua in run-time, start-up flag or at compilation time where this functionality can be switched off? Thanks in advance, Matti Zemack, BBC R&I, Kingswood Warren, UK http://www.bbc.co.uk/ This e-mail (and any attachments) is confidential and may contain personal views which are not the views of the BBC unless specifically stated. If you have received it in error, please delete it from your system. Do not use, copy or disclose the information in any way nor act in reliance on it and notify the sender immediately. Please note that the BBC monitors e-mails sent or received. Further communication will signify your consent to this. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20080115/70d1b602/attachment.html
