SIP/2.0 404 Not Found
From: <sip:nm@nm>;tag=root
To: <sip:nm2@nm2>;tag=b5f76cb8-bb9a24d-13c4-55013-6f30f-5b64edfb-6f30f
Call-ID: 50000
CSeq: 42 OPTIONS
Accept: application/sdp
Accept-Encoding: gzip
Allow: INVITE, ACK, BYE, NOTIFY, INFO, CANCEL, MESSAGE, OPTIONS
X-Serialnumber: ZTEEG8GH3M05438
User-Agent: SAH / V1.00-0x2C-0xDC / V10.C.24.12.11
Supported: replaces,timer
Via: SIP/2.0/UDP nm;received=224.110.133.116;rport=26810;branch=foo
Content-Length: 0