180 Ringing
183 Session Progress
200 OK
400 Bad Request
403 Forbidden
403 Not Authorized
404 Not Found
404 Not here
408 Request Timeout
410 Gone
480 Temporarily not available
480 Temporarily Unavailable
481 Call Leg/Transaction Does Not Exist
481 Call/Transaction Does Not Exist
482 Loop Detected
482 Request merged
484 Address Incomplete
486 Busy Here
486 User Busy
487 Request Cancelled
487 Request Terminated
487 Request Terminated CANCEL
487 transaction terminated
500 Internal Server Error
500 Server error occurred (1/TM)
500 Server error occurred (6/SL)
501 Not Implemented
503 Account Channel Limit Reached
503 Calling to that destination is not enabled
503 Circuit unavailable
503 EgressRateMax
503 Egress_NoRoute_Found
503 Egress_NoRoute_Found_A
503 NORMAL_CLEARING
503 Route cannot be found
503 Service Unavailable
503 SERVICE_UNAVAILABLE
504 Server Time-out
504 Server Timeout
600 Busy Everywhere
603 Decline
604 Does not exist anywhere
606 Not Acceptable