INVITE sip:user@example.com?Route=%3Csip:example.com%3E SIP/2.0
To: sip:user@example.com
From: sip:caller@example.net;tag=341518
Max-Forwards: 7
Contact: <sip:caller@host39923.example.net>
Call-ID: escruri.23940-asdfhj-aje3br-234q098w-fawerh2q-h4n5
CSeq: 149209342 INVITE
Via: SIP/2.0/UDP host-of-the-hour.example.com;branch=z9hG4bKkdjuw
Content-Type: application/sdp
Content-Length: 150

v=0
o=mhandley 29739 7272939 IN IP4 192.0.2.1
s=-
c=IN IP4 192.0.2.1
t=0 0
m=audio 49217 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
