OPTIONS sip:remote-target@example.com SIP/2.0<hex>2020</hex>
Via: SIP/2.0/TCP host1.example.com;branch=z9hG4bK299342093
To: <sip:remote-target@example.com>
From: <sip:local-resource@example.com>;tag=329429089
Call-ID: trws.oicu34958239neffasdhr2345r
Accept: application/sdp
CSeq: 238923 OPTIONS
Max-Forwards: 70
Content-Length: 0
