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Hangup Cause Mappings

Asterisk Hangup Cause Code Mappings

Asterisk Value ISDN Cause codes (Q.850 & Q.931 unless specified) MFC/R2 SIP/PJSIP Motif
AST_CAUSE_NOT_DEFINED Cause not defined OR2_CAUSE_UNSPECIFIED
AST_CAUSE_UNALLOCATED 1. Unallocated (unassigned) number
404, 485, 604
AST_CAUSE_NO_ROUTE_TRANSIT_NET 2. No route to specified transmit network
AST_CAUSE_NO_ROUTE_DESTINATION 3. No route to destination 420
AST_CAUSE_MISDIALLED_TRUNK_PREFIX 5. Misdialled trunk prefix (national use)
AST_CAUSE_CHANNEL_UNACCEPTABLE 6. Channel unacceptable
AST_CAUSE_CALL_AWARDED_DELIVERED 7. Call awarded and being delivered in an established channel
AST_CAUSE_PRE_EMPTED ISUP - 8. Preemption
AST_CAUSE_NUMBER_PORTED_NOT_HERE 14. QoR: ported number
AST_CAUSE_NORMAL_CLEARING 16. Normal Clearing OR2_CAUSE_NORMAL_CLEARING gone, success
AST_CAUSE_USER_BUSY 17. User busy OR2_CAUSE_BUSY_NUMBER 486, 600 busy
AST_CAUSE_NO_USER_RESPONSE 18. No user responding 408 expired
AST_CAUSE_NO_ANSWER 19. No answer from user (user alerted) OR2_CAUSE_NO_ANSWER 480, 483
AST_CAUSE_SUBSCRIBER_ABSENT 20. Subscriber absent OR2_CAUSE_UNALLOCATED_NUMBER
AST_CAUSE_CALL_REJECTED 21. Call Rejected 401, 403, 407, 603 cancel, decline
AST_CAUSE_NUMBER_CHANGED 22. Number changed 410
AST_CAUSE_REDIRECTED_TO_NEW_DESTINATION 23. Redirected to new destination
AST_CAUSE_ANSWERED_ELSEWHERE 26. Non-selected user clearing(ASTERISK-15057)
AST_CAUSE_DESTINATION_OUT_OF_ORDER 27. Destination out of order OR2_CAUSE_OUT_OF_ORDER 502
AST_CAUSE_INVALID_NUMBER_FORMAT 28. Invalid number format 484
AST_CAUSE_FACILITY_REJECTED 29. Facility rejected 501
AST_CAUSE_RESPONSE_TO_STATUS_ENQUIRY 30. Response to STATUS ENQUIRY
AST_CAUSE_NORMAL_UNSPECIFIED 31. Normal, unspecified
AST_CAUSE_NORMAL_CIRCUIT_CONGESTION 34. No circuit/channel available(Note that we've called this "Circuit/channel congestion" for a while which can cause confusion with code 42) OR2_CAUSE_NETWORK_CONGESTION general-error
AST_CAUSE_NETWORK_OUT_OF_ORDER 38. Network out of order 500
AST_CAUSE_NORMAL_TEMPORARY_FAILURE 41. Temporary failure 409
AST_CAUSE_SWITCH_CONGESTION 42. Switching equipment congestion 5xx failed-application
AST_CAUSE_ACCESS_INFO_DISCARDED 43. Access information discarded
AST_CAUSE_REQUESTED_CHAN_UNAVAIL 44. Requested circuit/channel not available
AST_CAUSE_FACILITY_NOT_SUBSCRIBED 50. Requested facility not subscribed
AST_CAUSE_OUTGOING_CALL_BARRED 52. Outgoing call barred
AST_CAUSE_INCOMING_CALL_BARRED 54. Incoming call barred
AST_CAUSE_BEARERCAPABILITY_NOTAUTH 57. Bearer capability not authorized
AST_CAUSE_BEARERCAPABILITY_NOTAVAIL 58. Bearer capability not presently available 488, 606 incompatible-parameters, media-error, unsupported-applications
AST_CAUSE_BEARERCAPABILITY_NOTIMPL 65. Bearer capability not implemented
AST_CAUSE_CHAN_NOT_IMPLEMENTED 66. Channel type not implemented
AST_CAUSE_FACILITY_NOT_IMPLEMENTED 69. Requested facility not implemented unsupported-transports
AST_CAUSE_INVALID_CALL_REFERENCE 81. Invalid call reference value
AST_CAUSE_INCOMPATIBLE_DESTINATION 88. Incompatible destination
AST_CAUSE_INVALID_MSG_UNSPECIFIED 95. Invalid message unspecified
AST_CAUSE_MANDATORY_IE_MISSING 96. Mandatory information element is missing
AST_CAUSE_MESSAGE_TYPE_NONEXIST 97. Message type non-existent or not implemented
AST_CAUSE_WRONG_MESSAGE 98. Message not compatible with call state or message type non-existent or not implemented
AST_CAUSE_IE_NONEXIST 99. Information element nonexistent or not implemented
AST_CAUSE_INVALID_IE_CONTENTS 100. Invalid information element contents
AST_CAUSE_WRONG_CALL_STATE 101. Message not compatible with call state
AST_CAUSE_RECOVERY_ON_TIMER_EXPIRE 102. Recover on timer expiry 504 timeout
AST_CAUSE_MANDATORY_IE_LENGTH_ERROR ? Mandatory IE length error
AST_CAUSE_PROTOCOL_ERROR 111. Protocol error, unspecified failed-transport, security-error
AST_CAUSE_INTERWORKING 127. Interworking, unspecified 4xx, 505, 6xx connectivity-error

Notes

  • The hangup cause AST_CAUSE_NOT_DEFINED is not actually a Q.931 cause code, and is used to capture hangup causes that do not map cleanly to a Q.931 cause code.
  • IAX2, ISDN, and SS7 are all subsets of the cause codes listed above.
  • Analog will always have a hangup cause code of AST_CAUSE_NORMAL_CLEARING.
  • SIP causes of 4xx, 5xx, and 6xx correspond to all 400, 500, and 600 response codes not explicitly listed in the table above.
  • AST_CAUSE_UNREGISTERED maps to AST_CAUSE_SUBSCRIBER_ABSENT. This error condition is raised when the endpoint is known but has unregistered itself somehow from Asterisk, e.g., a SIP peer has not registered or sent a REGISTER request with an expiration of 0.