freeswitch@voip> recv 535 bytes from udp/[client-IP]]:50208 at 10:54:42.236167:
   ------------------------------------------------------------------------
   REGISTER sip:[server-IP] SIP/2.0
   Via: SIP/2.0/UDP client-IP]:50208;branch=z9hG4bK-524287-1---ccc29d0189d78c75;rport
   Max-Forwards: 70
   Contact: <sip:5519@client-IP]:50208;rinstance=c83c0f3536ea39dd>
   To: <sip:5519@[server-IP]>
   From: <sip:5519@[server-IP]>;tag=83c9a75e
   Call-ID: 79048NzQ2YmMwZTEyYjA2MWM5Y2E0ZTgwNzM4YTMzMjg5MzQ
   CSeq: 1 REGISTER
   Expires: 3600
   Allow: SUBSCRIBE, NOTIFY, INVITE, ACK, CANCEL, BYE, REFER, INFO, MESSAGE, OPTIONS
   User-Agent: X-Lite release 4.9.2 stamp 79048
   Content-Length: 0

   ------------------------------------------------------------------------
send 642 bytes to udp/[client-IP]]:50208 at 10:54:42.236870:
   ------------------------------------------------------------------------
   SIP/2.0 401 Unauthorized
   Via: SIP/2.0/UDP client-IP]:50208;branch=z9hG4bK-524287-1---ccc29d0189d78c75;rport=50208
   From: <sip:5519@[server-IP]>;tag=83c9a75e
   To: <sip:5519@[server-IP]>;tag=Qc8cXpySm6j6F
   Call-ID: 79048NzQ2YmMwZTEyYjA2MWM5Y2E0ZTgwNzM4YTMzMjg5MzQ
   CSeq: 1 REGISTER
   User-Agent: FreeSWITCH-mod_sofia/1.6.5+git~20151120T205750Z~70b8c17763~64bit
   Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, INFO, UPDATE, REGISTER, REFER, NOTIFY
   Supported: timer, path, replaces
   WWW-Authenticate: Digest realm="[server-IP]", nonce="661a9cb4-e1c9-11e5-b4ff-032d1fb17ba1", algorithm=MD5, qop="auth"
   Content-Length: 0

   ------------------------------------------------------------------------
recv 792 bytes from udp/[client-IP]]:50208 at 10:54:42.244841:
   ------------------------------------------------------------------------
   REGISTER sip:[server-IP] SIP/2.0
   Via: SIP/2.0/UDP client-IP]:50208;branch=z9hG4bK-524287-1---583c5f02d4cdab70;rport
   Max-Forwards: 70
   Contact: <sip:5519@client-IP]:50208;rinstance=c83c0f3536ea39dd>
   To: <sip:5519@[server-IP]>
   From: <sip:5519@[server-IP]>;tag=83c9a75e
   Call-ID: 79048NzQ2YmMwZTEyYjA2MWM5Y2E0ZTgwNzM4YTMzMjg5MzQ
   CSeq: 2 REGISTER
   Expires: 3600
   Allow: SUBSCRIBE, NOTIFY, INVITE, ACK, CANCEL, BYE, REFER, INFO, MESSAGE, OPTIONS
   User-Agent: X-Lite release 4.9.2 stamp 79048
   Authorization: Digest username="5519",realm="[server-IP]",nonce="661a9cb4-e1c9-11e5-b4ff-032d1fb17ba1",uri="sip:[server-IP]",response="5080778be7af102e08e9d1e161944e34",cnonce="6935d825ba40e4863816452de3b084b3",nc=00000001,qop=auth,algorithm=MD5
   Content-Length: 0

   ------------------------------------------------------------------------
send 515 bytes to udp/[client-IP]]:50208 at 10:54:42.245907:
   ------------------------------------------------------------------------
   SIP/2.0 403 Forbidden
   Via: SIP/2.0/UDP client-IP]:50208;branch=z9hG4bK-524287-1---583c5f02d4cdab70;rport=50208
   From: <sip:5519@[server-IP]>;tag=83c9a75e
   To: <sip:5519@[server-IP]>;tag=rN15yHFXHF9rB
   Call-ID: 79048NzQ2YmMwZTEyYjA2MWM5Y2E0ZTgwNzM4YTMzMjg5MzQ
   CSeq: 2 REGISTER
   User-Agent: FreeSWITCH-mod_sofia/1.6.5+git~20151120T205750Z~70b8c17763~64bit
   Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, INFO, UPDATE, REGISTER, REFER, NOTIFY
   Supported: timer, path, replaces
   Content-Length: 0

   ------------------------------------------------------------------------