;tag=[call_number] To: Call-ID: [call_id] CSeq: [cseq] INVITE Contact: sip:[local_ip]:[local_port] Max-Forwards: 10 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/AVP 0 8 a=rtpmap:0 PCMU/8000 a=rtpmap:8 PCMA/8000 ]]>