Polycom SIP 3.1 - Manual (Page 290)

Administrator’s Guide SoundPoint IP / SoundStation IP
B - 8
5xx Responses - Server Failure
6xx Responses - Global Failure
481 Call/Transaction Does Not Exist Yes
482 Loop Detected Yes
483 Too Many Hops No
484 Address Incomplete Yes
485 Ambiguous No
486 Busy Here Yes
487 Request Terminated Yes
488 Not Acceptable Here Yes
491 Request Pending No
493 Undecipherable No
Response Supported Notes
Response Supported Notes
500 Server Internal Error Yes
501 Not Implemented Yes
502 Bad Gateway No
503 Service Unavailable No
504 Server Time-out No
505 Version Not Supported No
513 Message Too Large No
Response Supported Notes
600 Busy Everywhere No
603 Decline Yes
604 Does Not Exist Anywhere No
606 Not Acceptable No