The normal registration sequence.
send 808 bytes to udp/[27.111.14.67]:5060 at 18:53:19.023006:
   ------------------------------------------------------------------------
   REGISTER sip:sip.kiwilink.co.nz;transport=udp SIP/2.0
   Via: SIP/2.0/UDP 192.168.1.61;rport;branch=z9hG4bKtcNpQypm1N8rp
   Max-Forwards: 70
   From: <sip:095290110@kiwilink.co.nz>;tag=cQmjvaQ6rtape
   To: <sip:095290110@kiwilink.co.nz>
   Call-ID: f6f9fb18-e3ad-41ec-9115-fc5fba6cd47e
   CSeq: 57081554 REGISTER
   Contact: <sip:gw+outbound2@192.168.1.61:5060;transport=udp;gw=outbound2>
   Expires: 180
   User-Agent: FreeSWITCH-mod_sofia/1.5.7b+git~20131111T224713Z~5456daa010~32bit
   Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, INFO, UPDATE, REGISTER, REFER, NOTIFY
   Supported: timer, precondition, path, replaces
   Authorization: Digest username="095290110", realm="voip", nonce="60f381b0", algorithm=MD5, uri="sip:sip.kiwilink.co.nz;transport=udp", response="a00513b45bea998c2f5dcdc89e9d8194"
   Content-Length: 0
   
   ------------------------------------------------------------------------
recv 510 bytes from udp/[27.111.14.67]:5060 at 18:53:19.070009:
   ------------------------------------------------------------------------
   SIP/2.0 401 Unauthorized
   Via: SIP/2.0/UDP 192.168.1.61;branch=z9hG4bKtcNpQypm1N8rp;received=192.168.1.61;rport=5061
   From: <sip:095290110@kiwilink.co.nz>;tag=cQmjvaQ6rtape
   To: <sip:095290110@kiwilink.co.nz>;tag=as3c84c7e2
   Call-ID: f6f9fb18-e3ad-41ec-9115-fc5fba6cd47e
   CSeq: 57081554 REGISTER
   Server: NZ PBX
   Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH
   Supported: replaces
   WWW-Authenticate: Digest algorithm=MD5, realm="voip", nonce="06c78ba3"
   Content-Length: 0
   
   ------------------------------------------------------------------------
send 808 bytes to udp/[27.111.14.67]:5060 at 18:53:19.070009:
   ------------------------------------------------------------------------
   REGISTER sip:sip.kiwilink.co.nz;transport=udp SIP/2.0
   Via: SIP/2.0/UDP 192.168.1.61;rport;branch=z9hG4bKUNeFSS7QyyyBj
   Max-Forwards: 70
   From: <sip:095290110@kiwilink.co.nz>;tag=cQmjvaQ6rtape
   To: <sip:095290110@kiwilink.co.nz>
   Call-ID: f6f9fb18-e3ad-41ec-9115-fc5fba6cd47e
   CSeq: 57081555 REGISTER
   Contact: <sip:gw+outbound2@192.168.1.61:5060;transport=udp;gw=outbound2>
   Expires: 180
   User-Agent: FreeSWITCH-mod_sofia/1.5.7b+git~20131111T224713Z~5456daa010~32bit
   Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, INFO, UPDATE, REGISTER, REFER, NOTIFY
   Supported: timer, precondition, path, replaces
   Authorization: Digest username="095290110", realm="voip", nonce="06c78ba3", algorithm=MD5, uri="sip:sip.kiwilink.co.nz;transport=udp", response="42a07880d590706ad3eec635e76e1c9a"
   Content-Length: 0
   
   ------------------------------------------------------------------------
recv 577 bytes from udp/[27.111.14.67]:5060 at 18:53:19.118012:
   ------------------------------------------------------------------------
   OPTIONS sip:gw+outbound2@192.168.1.61:5060;transport=udp;gw=outbound2 SIP/2.0
   Via: SIP/2.0/UDP 27.111.14.67:5060;branch=z9hG4bK71c7a86a
   Max-Forwards: 70
   From: "nzpbx" <sip:nzpbx@27.111.14.67>;tag=as6402fa2f
   To: <sip:gw+outbound2@192.168.1.61:5060;transport=udp;gw=outbound2>
   Contact: <sip:nzpbx@27.111.14.67:5060>
   Call-ID: 4ffdaf94456044707282c839722414b6@27.111.14.67
   CSeq: 102 OPTIONS
   User-Agent: NZ PBX
   Date: Sat, 15 Mar 2014 18:53:19 GMT
   Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH
   Supported: replaces
   Content-Length: 0
   
   ------------------------------------------------------------------------
send 666 bytes to udp/[27.111.14.67]:5060 at 18:53:19.119012:
   ------------------------------------------------------------------------
   SIP/2.0 200 OK
   Via: SIP/2.0/UDP 27.111.14.67:5060;branch=z9hG4bK71c7a86a
   From: "nzpbx" <sip:nzpbx@27.111.14.67>;tag=as6402fa2f
   To: <sip:gw+outbound2@192.168.1.61:5060;transport=udp;gw=outbound2>;tag=88SZU8DQN59rm
   Call-ID: 4ffdaf94456044707282c839722414b6@27.111.14.67
   CSeq: 102 OPTIONS
   Contact: <sip:gw+2talk@192.168.1.61:5060;transport=udp;gw=2talk>
   User-Agent: FreeSWITCH-mod_sofia/1.5.7b+git~20131111T224713Z~5456daa010~32bit
   Accept: application/sdp
   Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, INFO, UPDATE, REGISTER, REFER, NOTIFY
   Supported: timer, precondition, path, replaces
   Allow-Events: talk, hold, conference, refer
   Content-Length: 0
   
   ------------------------------------------------------------------------
recv 565 bytes from udp/[27.111.14.67]:5060 at 18:53:19.120012:
   ------------------------------------------------------------------------
   SIP/2.0 200 OK
   Via: SIP/2.0/UDP 192.168.1.61;branch=z9hG4bKUNeFSS7QyyyBj;received=192.168.1.61;rport=5061
   From: <sip:095290110@kiwilink.co.nz>;tag=cQmjvaQ6rtape
   To: <sip:095290110@kiwilink.co.nz>;tag=as3c84c7e2
   Call-ID: f6f9fb18-e3ad-41ec-9115-fc5fba6cd47e
   CSeq: 57081555 REGISTER
   Server: NZ PBX
   Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH
   Supported: replaces
   Expires: 180
   Contact: <sip:gw+outbound2@192.168.1.61:5060;transport=udp;gw=outbound2>;expires=180
   Date: Sat, 15 Mar 2014 18:53:19 GMT
   Content-Length: 0