REGISTER sip:example.com SIP/2.0
Via: SIP/2.0/TCP host129.example.com;branch=z9hG4bK342sdfoi3
To: <sip:user@example.com>
From: <sip:user@example.com>;tag=239232jh3
CSeq: 36893488147419103232 REGISTER
Call-ID: scalar02.23o0pd9vanlq3wnrlnewofjas9ui32
Max-Forwards: 300
Expires: 1<repeat count=100>0</repeat>
Contact: <sip:user@host129.example.com>
  ;expires=280297596632815
Content-Length: 0
