Alex Hermann writes: > > rtpproxy_offer and answer functions have "r" flag described as follows: > > > > r - flags that IP address in SDP should be trusted. Without this flag, > > rtpproxy ignores address in the SDP and uses source address of the SIP > > message as media address which is passed to the RTP proxy. > > > > how does rtpproxy "use" this ip address? > > It directly starts forwarding packets to it. If you don't use this flag, > rtpproxsy will wait until it has received poackets from both parties in the > call.
it is not what the above description tells. it just tells where rtpproxy takes the address, nothing about when it starts to send packets. proper use of rtpproxy or mediaproxy-ng is difficult until this has been clarified. waiting for both parties to send something first, would not work if the other party is muted. > > if sip message comes from behind nat, ip address in sdp is local > > address, not the address where rtp packets come from. and if this > > request has passed another (e.g. outbound) proxy before hitting the > > current one, also source address of sip message is not the address where > > rtp packets come from. either address thus seems to be useless for > > rtpproxy. > > You can make the addres more "usefull" by rewriting the address with > fix_natted_sdp() on the first proxy the UAC reaches (load-balancer). If you > don't have that possibility, maybe you can call fix_natted_sdp() on the proxy > itself and call msg_apply_changes() before invoking the rtpproxy. it would result in double rewrite of the sdp when one motivation of using mediaproxy-ng is that it does the rewriting only once. there should be possibility pass sdp ip address as parameter in offer and answer calls. -- juha _______________________________________________ SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list sr-users@lists.sip-router.org http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
