ACK sip:company.com SIP/2.0
To: sip:j.user@company.com
From: sip:j.user@company.com
Call-ID: 0ha0isndaksdj@10.0.2.2
Contact: sip:j.user@host.company.com
CSeq: 8 NEWMETHOD
Via: SIP/2.0/UDP 135.180.130.133
Content-Length: 0