Something

Rx-Frame Retry[ No] -- OSeqno: 000 ISeqno: 000 Type: IAX     Subclass: NEW
   Timestamp: 00003ms  SCall: 05910  DCall: 00000 [192.168.1.100:4569]
   VERSION         : 2
   CALLING NUMBER  : 7005551212
   CALLING NAME    : Not Available
   FORMAT          : 2
   CAPABILITY      : 2
   USERNAME        : simon
   CALLED NUMBER   : 200
   DNID            : 200

Feb 10 16:52:49 NOTICE[7721]: chan_iax2.c:6775 socket_read: Rejected connect attempt from 192.168.1.100, who was trying to reach '200@'
Tx-Frame Retry[000] -- OSeqno: 000 ISeqno: 001 Type: IAX     Subclass: REJECT
   Timestamp: 00014ms  SCall: 00001  DCall: 05910 [192.168.1.100:4569]
   CAUSE           : No authority found
   CAUSE CODE      : 50

Rx-Frame Retry[ No] -- OSeqno: 001 ISeqno: 001 Type: IAX     Subclass: ACK
   Timestamp: 00014ms  SCall: 05910  DCall: 00001 [192.168.1.100:4569]