On Mon, Jun 16, 2008 at 9:48 AM, Pedro Gon?alves <pedro.pandre at gmail.com> wrote: > I already succeeded to send the initial offer in the INVITE: > 1) I configured and resolved a stun server, calling pj_stun_config_init > 2) I created the ICE Transport, by calling pjmedia_ice_create > 3) I initialized the ICE Transport, by calling pjmedia_ice_start_init > 4) I initialized the ICE Session, by calling pjmedia_ice_init_ice > 5) I modified SDP to include ICE candidates, by calling > pjmedia_ice_modify_sdp > > Then, the modified INVITE is sent to the callee, which receives it. > Now, how shall I proceed so that the callee makes a similar group of actions > in order to gather its own candidates? I know that in the end, the callee > can start ICE connectivity checks, right? First of all I think you're using old (probably 0.8 release) version of pjsip, the latest SVN version has different API. So with the latest code, here's how to do it: - Initially call pjmedia_ice_create() with the appropriate pj_ice_strans_cfg. The initialization will complete asynchronously and the ICE media transport callback will be called when initialization completes (STUN mapping is found, TURN allocation is done, etc.). - When creating an offer, call pjmedia_transport_media_create() with local SDP (and NULL as rem_sdp). The ICE media transport will add the relevant ICE attributes in the local SDP. Then give the local SDP to the invite session. - When creating an answer, also call pjmedia_transport_media_create(), but this time give both local and remote SDP to it. The ICE media transport will once again modify the local SDP and add ICE attributes to local SDP, if ICE attributes are indeed found in remote offer. If not, then it won't add ICE attributes, and ICE will not get activated. - When you have both local and remote SDP, and when media is okay to be created, call pjmedia_transport_media_start(), once again giving it both local and remote SDP. ICE negotiation will start now and ICE media transport callback will be called when ICE negotiation completes. As you probably notice by now, this mechanism should be generic enough to cover other media transports not only ICE, and indeed this is how we do it for SRTP as well. For more info please see http://www.pjsip.org/pjmedia/docs/html/group__PJMEDIA__TRANSPORT__H.htm > BTW, callee's candidates will be sent in which answer? INVITE 100 Trying? > INVITE 180 Ringing? INVITE 200 OK? > Whenever you want to send SDP, normally not in 180, and definitely not in 100. Cheers Benny > Best Regards > Pedro Gon?alves > > _______________________________________________ > Visit our blog: http://blog.pjsip.org > > pjsip mailing list > pjsip at lists.pjsip.org > http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org > >
