------------------------------------------------------------------------
   REGISTER sip:ims.airtel.in;transport=udp SIP/2.0
   Via: SIP/2.0/UDP 10.100.104.138:5090;rport;branch=z9hG4bKHHFe953FDeX3m
   Max-Forwards: 70
   From: <sip:XXX@ims.airtel.in>;tag=K7jKp2Q7QF27H
   To: <sip:XXX@ims.airtel.in>
   Call-ID: c59a632b-7339-4393-9f4f-2bd9239a77b9
   CSeq: 134041262 REGISTER
   Contact: <sip:XXX@10.100.XXX.XXX:5090;transport=udp;gw=airtel-profile>
   Expires: 3600
   User-Agent: FreeSWITCH-mod_sofia/1.8.4-5-749a6e108b~64bit
   Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, INFO, UPDATE, REGISTER, REFER, NOTIFY
   Supported: timer, path, replaces
   Content-Length: 0
   
   ------------------------------------------------------------------------