;tag=[call_number] To: Call-ID: [call_id] CSeq: [cseq] INVITE Contact: Max-Forwards: 100 User-Agent: SIPp/sippy_cup Content-Type: application/sdp Content-Length: [len] v=0 o=user1 53655765 2353687637 IN IP[local_ip_type] [local_ip] s=- c=IN IP[media_ip_type] [media_ip] t=0 0 m=audio [media_port] RTP/AVPF 0 101 a=rtcp:[media_port+1] a=rtpmap:0 PCMU/8000 a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-15 ]]> ;tag=[call_number] [last_To:] Call-ID: [call_id] CSeq: [cseq] ACK Contact: Max-Forwards: 100 User-Agent: SIPp/sippy_cup Content-Length: 0 [routes] ]]> Max-Forwards: 100 User-Agent: SIPp/sippy_cup Content-Length: 0 [routes] ]]>