List of Cause Codes for Calls

CauseCode	Text	Description
UNALLOCATED_NUMBER	Unallocated (unassigned) number	This cause indicates that the destination requested by the calling user cannot be reached because, though the number is in a valid format, it is not currently assigned (allocated).
NO_ROUTE_TO_NETWORK	No route to specified transit network	This cause indicates that the equipment sending this cause has received a request to route the call through a particular transit network that it does not recognize. This could be because the transit network does not exist or because that particular transit network does not serve the equipment which is sending this cause.
NO_ROUTE_TO_DESTINATION	No route to destination	This cause indicates that the called party cannot be reached because the network through which the call has been routed does not serve the destination desired. This cause is supported on a network-dependent basis.
SPECIAL_INFORMATION_TONE	send special information tone	This cause indicates that the called party cannot be reached for reasons that are of a long-term nature and that the special information tone should be returned to the calling party.
MISDIALED_TRUNK_PREFIX	misdialed trunk prefix	This cause indicates the erroneous inclusion of a trunk prefix in the called party number. This number is to snipe from the dialed number being sent to the network by the customer premises equipment.
CHANNEL_UNACCEPTABLE	channel unacceptable	This cause indicates that the channel most recently identified is not acceptable to the sending entity for use in this call.
CALL_AWARDED_ESTABLISHED_CHANNEL	call awarded. being delivered in an established channel	This cause indicates that the user has been awarded the incoming call and that the incoming call is being connected to a channel already established to that user for similar calls (e.g. packet-mode x.25 virtual calls).
PREEMPTION	preemption	This cause indicates the call is being preempted.
PREEMPTION_REUSE	preemption - circuit reserved for reuse	This cause indicates that the call is being preempted and the circuit is reserved for reuse by the preempting exchange.
NORMAL_CLEARNING	normal call clearing	This cause indicates that the call is being cleared because one of the users involved in the call has requested that the call be cleared. This could mean Telephone line problems. Hung session on the remote end.
USER_BUSY	User busy	This cause is used to indicate that the called party is unable to accept another call because the user's busy condition has been encountered. This cause value may be generated by the called user or by the network. In the case of user-determined user busy, it is noted that the user equipment is compatible with the call.
NO_USER_RESPONDING	no user responding	This cause is used when a called party does not respond to a call establishment message with either an alerting or connect indication within the prescribed period of time allocated.
NO_ANSWER	no answer from the user	This cause is used when the called party has been alerted but does not respond with a connect indication within a prescribed period of time. Note - This cause is not necessarily generated by Q.931 procedures but may be generated by internal network timers.
SUBSCRIBER_ABSENT	subscriber absent	This cause value is used when a mobile station has logged off. Radio contact is not obtained with a mobile station or if a personal telecommunication user is temporarily not addressable at any user-network interface
CALL_REJECTED	call rejected	This cause indicates that the equipment sending this cause does not wish to accept this call. although it could have accepted the call because the equipment sending this cause is neither busy nor incompatible. This cause may also be generated by the network, indicating that the call was cleared due to a supplementary service constraint. The diagnostic field may contain additional information about the supplementary service and the reason for rejection.
NUMBER_CHANGED	number changed	This cause is returned to a calling party when the called party number indicated by the calling party is no longer assigned. The new called party number may optionally be included in the diagnostic field. If a network does not support this cause, cause no. 1, unallocated (unassigned) number shall be used
NON_SELECTED_USER_CLEARNING	non-selected user clearing	This cause indicates that the user has not been awarded the incoming call.
DESTINATION_OUT_OF_ORDER	destination out of order	This cause indicates that the destination indicated by the user cannot be reached because the interface to the destination is not functioning correctly. The term "not functioning correctly" indicates that a signal message was unable to be delivered to the remote party; e.g., a physical layer or data link layer failure at the remote party or user equipment off-line.
INVALID_NUMBER_FORMAT	invalid number format	This cause indicates that the called party cannot be reached because the called party number is not in a valid format or is not complete
FACILITIES_REJECTED	facilities rejected	This cause is returned when a supplementary service requested by the user cannot be provided by the network
STATUS_INQUIRY_RESPONSE	response to STATUS INQUIRY	This cause is included in the STATUS message when the reason for generating the STATUS message was the prior receipt of a STATUS INQUIRY.
NORMAL_UNSPECIFIED	normal. unspecified	This cause is used to report a normal event only when no other cause in the normal class applies
NO_CHANNEL_AVAILABLE	no circuit/channel available	This cause indicates that there is no appropriate circuit/channel presently available to handle the call.
CALL_QUEUED	Call Queued
NETWORK_OUT_OF_ORDER	network out of order.	This cause indicates that the network is not functioning correctly and that the condition is likely to last a relatively long period of time e.g., immediately re-attempting the call is not likely to be successful
CONNECTION_OUT_OF_SERVICE	permanent frame mode connection out-of-service	This cause is included in a STATUS message to indicate that a permanently established frame mode connection is out-of-service (e.g. due to equipment or section failure)
CONNECTION_OPERATIONAL	permanent frame mode connection operational	This cause is included in a STATUS message to indicate that a permanently established frame mode connection is operational and capable of carrying user information
TEMPORARY_FAILURE	temporary failure	This cause indicates that the network is not functioning correctly and that the condition is not likely to last a long period of time; e.g., the user may wish to try another call attempt almost immediately.
SWITCHING_EQUIPMENT_CONGESTION	switching equipment congestion	This cause indicates that the switching equipment generating this cause is experiencing a period of high traffic
ACCESS_INFO_DISCARDED	access information discarded	This cause indicates that the network could not deliver access information to the remote user as requested i.e., user-to-user information, low layer compatibility, high layer compatibility, or sub-address as indicated in the diagnostic. It is noted that the particular type of access information discarded is optionally included in the diagnostic
CHANNEL_NOT_AVAILABLE	requested circuit/channel not available	This cause is returned when the circuit or channel indicated by the requesting entity cannot be provided by the other side of the interface
PRECEDENCE_CALL_BLOCKED	precedence call blocked	This cause indicates that there are no predictable circuits or that the dialed user is busy with a call of equal or higher preventable level
RESOURCE_UNAVAILABLE	resource unavailable, unspecified	This cause is used to report a resource unavailable event only when no other cause in the resource unavailable class applies
QOS_NOT_AVAILABLE	Quality of Service not available	This cause is used to report the requested Quality of Service, as defined in Recommendation X.213. cannot be provided (e.g., the throughput of transit delay cannot be supported)
FACILITY_NOT_SUBSCRIBED	requested facility not subscribed	This cause indicates that the user has requested a supplementary service which is implemented by the equipment which generated this cause but the user is not authorized to use The switch looks at the number being dialed and thinks it is for another service rather than ISDN. If the phone number is put in the correct format, the call should be placed properly. There are no standards for this, all Telcos have their own system for programming the number formats that the switches will recognize. Some systems want to see 7 digits, some 10, and others 11.
OUTGOING_CALLS_BARRED	outgoing calls barred
OUTGOING_CALLS_BARRED_CUG	outgoing calls barred within CUG	This cause indicates that although the calling party is a member of the CUG for the outgoing CUG call. Outgoing calls are not allowed for this member of the CUG
INCOMING_CALLS_BARRRED	incoming calls barred
INCOMING_CALLS_BARRRED_CUG	incoming calls barred within CUG	This cause indicates that although the calling party is a member of the CUG for the incoming CUG call. Incoming calls are not allowed for this member of the CUG
BEARER_CAPABILITY_NOT_AUTHORIZED	bearer capability not authorized	This cause indicates that the user has requested a bearer capability which is implemented by the equipment which generated this cause but the user is not authorized to use
BEARER_CAPABILITY_NOT_AVAILABLE	bearer capability is not presently available	This cause indicates that the user has requested a bearer capability which is implemented by the equipment which generated this cause but which is not available at this time
INCONSISTENT_OUTGOING_INFO_ELEMENT	inconsistency in the outgoing information element	This cause indicates an inconsistency in the designated outgoing access information and subscriber class
SERVICE_NOT_AVAILABLE	service or option not available. unspecified.	This cause is used to report a service or option not available event only when no other cause in the service or option not available class applies
BEARER_CAPABILITY_NOT_IMPLEMENTED	bearer capability not implemented	This cause indicates that the equipment sending this cause does not support the bearer capability requested. What it means: In most cases, the number being called is not an ISDN number but an analog destination. The equipment is dialing at a faster rate than the circuitry allows, for example, dialing at 64K when only 56K is supported
CHANNEL_TYPE_NOT_IMPLEMENTED	channel type not implemented	This cause indicates that the equipment sending this cause does not support the channel type requested
FACILITY_NOT_IMPLEMENTED	requested facility not implemented	This cause indicates that the equipment sending this cause does not support the requested supplementary services
RESTRICTED_BEARER_CAPABILITY_AVAILABLE	only restricted digital information bearer capability is available	This cause indicates that the calling party has requested an unrestricted bearer service but the equipment sending this cause only supports the restricted version of the requested bearer capability
SERVICE_NOT_IMPLEMENTED	service or option not implemented unspecified	This cause is used to report a service or option not implemented event only when no other cause in the service or option not implemented class applies
INVALID_CALL_REFERENCE_VALUE	invalid call reference value	This cause indicates that the equipment sending this cause has received a message with a call reference that is not currently in use on the user-network interface.
CHANNEL_DOES_NOT_EXIST	identified channel does not exist	This cause indicates that the equipment sending this cause has received a request to use a channel not activated on the interface for a call. For example, if a user has subscribed to those channels on a primary rate interface numbered from l to 12 and the user equipment or the network attempts to use channels 3 through 23, this cause is generated.
SUSPENDED_CALL_EXISTS	A suspended call exists, but this call identify does not	This cause indicates that a call resume has been attempted with a call identity that differs from that in use for any presently suspended call(s).
CALL_IDENTITY_INUSE	call identity in use	This cause indicates that the network has received a call suspended request containing a call identity (including the null call identity) that is already in use for a suspended call within the domain of interfaces over which the call might be resumed
NO_CALL_SUSPENDED	no call suspended	This cause indicates that the network has received a call resume request containing a call identity information element which presently does not indicate any suspended call within the domain of interfaces over which calls may be resumed
CALL_IDENTITY_CLEARED	call having the requested call identity has been cleared	This cause indicates that the network has received a call resume request containing a call identity information element indicating a suspended call that has in the meantime been cleared while suspended (either by network time-out or by the remote user)
USER_NOT_MEMBER_OF_CUG	user not a member of CUG	This cause indicates that the called user for the incoming CUG call is not a member of the specified CUG or that the calling user is an ordinary subscriber calling a CUG subscriber.
INCOMPATIBLE_DESTINATION	incompatible destination	This cause indicates that the equipment sending this cause has received a request to establish a call that has low layer compatibility. high layer compatibility or other compatibility attributes (e.g., data rate) which cannot be accommodated
NON_EXISTENT_CUG	non-existent CUG	This cause indicates that the specified CUG does not exist.
INVALID_TRANSIT_NETWORK_SELECTION	invalid transit network selection	This cause indicates that a transit network identification was received which is of an incorrect format as defined in Annex C/Q.931
INVALID_MESSAGED	invalid message, unspecified	This cause is used to report an invalid message event only when no other cause in the invalid message class applies.
MANDATORY_INFO_ELEMENT_MISSING	mandatory information element is missing	This cause indicates that the equipment sending this cause has received a message which is missing an information element that must be present in the message before that message can be processed
MESSAGE_TYPE_NON_EXISTENT	message type non-existent or not implemented	This cause indicates that the equipment sending this cause has received a message with a message type it does not recognize either because this is a message not defined of defined but not implemented by the equipment sending this cause
MESSAGE_NOT_COMPATIBLE	message not compatible with call state or message type non-existent	This cause indicates that the equipment sending this cause has received a message such that the procedures do not indicate that this is a permissible message to receive while in the call state, or a STATUS message was received indicating an incompatible call state
INFO_ELEMENT_NON_EXISTENT	Information element / parameter non-existent or not implemented	This cause indicates that the equipment sending this cause has received a message which includes information element(s)/parameter(s) not recognized because the information element(s)/parameter name(s) are not defined or are defined but not implemented by the equipment sending the cause. This cause indicates that the information element(s)/parameter(s) were discarded. However, the information element is not required to be present in the message in order for the equipment sending the cause to process the message
INVALID_INFO_ELEMENT_CONTENTS	Invalid information element contents	This cause indicates that the equipment sending this cause has received an information element that it has implemented; however, one or more of the fields in the information element are coded in such a way that has not been implemented by the equipment sending this cause
MESSAGE_NOT_COMPABITLE_CALL_STATE	message not compatible with call state	This cause indicates that a message has been received which is incompatible with the call state.
RECOVERY_ON_TIMER_EXPIRY	recovery on timer expiry	This cause indicates that a procedure has been initiated by the expiration of a timer in association with error handling procedures
PARAMETER_NON_EXISTENT	parameter non-existent or not implemented - passed on	This cause indicates that the equipment sending this cause has received a message which includes parameters not recognized because the parameters are not defined or are defined but not implemented by the equipment sending this cause. The cause indicates that the parameter(s) were ignored. In addition, if the equipment sending this cause is an intermediate point, then this cause indicates that the parameter(s) were passed unchanged
MESSAGE_WITH_UNRECOGNIZED_PARAMETER	message with unrecognized parameter discarded	This cause indicates that the equipment sending this cause has discarded a received message which includes a parameter that is not recognized
PROTOCOL_ERROR	protocol error, unspecified	This cause is used to report a protocol error event only when no other cause in the protocol error class applies
INTEL_WORKING	Intel-working, unspecified	This cause indicates that an interworking call (usually a call to 5W56 service) has ended