Hi Stephen,

thanks for your rapid reply.

I use kamailio as SIP proxy server . when ua1 is calling to ua2,

it will receive early media from kamailio while ua2 is busy(send

486 reply code).

 

All sip messages pass kamailio, ua1 and ua2 are not natted cliend.

and i want not to use any media server such as sems etc.

 

Hi Zhou,

You will need to use something like rtpproxy - 

There is a thread discussing it here:

http://www.mail-archive.com/users@lists.kamailio.org/msg06532.html

HTH.

Regards,

Stephen