;tag=[call_number]
To: [service]
Call-ID: [call_id]
CSeq: 1 INVITE
Contact: sip:sipp@[local_ip]:[local_port]
Max-Forwards: 70
Content-Type: application/sdp
Content-Length: [len]
v=0
o=- 42 42 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 [pt]
a=rtpmap:[pt] [codec]
a=recvonly
]]>
;tag=[call_number]
To: [service] [peer_tag_param]
Call-ID: [call_id]
CSeq: 1 ACK
Contact: sip:sipp@[local_ip]:[local_port]
Max-Forwards: 70
Content-Length: 0
]]>
Content-Length: 0
]]>