Call Cause Codes

cause codes provide granular information about a call status to help you understand what happened with a call these cause codes are primarily derived by exotel as per the operators these are currently exposed via our passthru applet cause codes ranging from 1 127 are as per the isdn standard cause causecode text description 1 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) 2 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 3 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 4 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 5 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 6 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 7 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) 8 preemption preemption this cause indicates the call is being preempted 9 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 16 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 17 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 18 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 19 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 20 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 21 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 22 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 26 non selected user clearning non selected user clearing this cause indicates that the user has not been awarded the incoming call 27 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 28 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 29 facilities rejected facilities rejected this cause is returned when a supplementary service requested by the user cannot be provided by the network 30 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 31 normal unspecified normal unspecified this cause is used to report a normal event only when no other cause in the normal class applies 34 no channel available no circuit/channel available this cause indicates that there is no appropriate circuit/channel presently available to handle the call 35 call queued call queued 38 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 39 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) 40 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 41 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 42 switching equipment congestion switching equipment congestion this cause indicates that the switching equipment generating this cause is experiencing a period of high traffic 43 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 44 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 46 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 47 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 49 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) 50 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 52 outgoing calls barred outgoing calls barred 53 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 54 incoming calls barrred incoming calls barred 55 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 57 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 58 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 62 inconsistent outgoing info element inconsistency in the outgoing information element this cause indicates an inconsistency in the designated outgoing access information and subscriber class 63 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 65 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 66 channel type not implemented channel type not implemented this cause indicates that the equipment sending this cause does not support the channel type requested 69 facility not implemented requested facility not implemented this cause indicates that the equipment sending this cause does not support the requested supplementary services 70 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 79 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 81 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 82 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 83 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) 84 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 85 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 86 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) 87 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 88 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 90 non existent cug non existent cug this cause indicates that the specified cug does not exist 91 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 95 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 96 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 97 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 98 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 99 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 100 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 101 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 102 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 103 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 110 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 111 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 127 intel working intel working, unspecified this cause indicates that an interworking call (usually a call to 5w56 service) has ended notes about cause codes over 128 according to the isdn spec “cause code values of 128 and higher aren't sent over the network a terminal displaying a value 128 or higher and claiming it is a cause code arguably has a bug or is implementing some proprietary diagnostic code (not necessarily bad) some commendation has cause codes listed with numbers higher than 128, but at this time they are proprietary in nature ” cause codes ranging beyond 1000 are constructed by exotel based on certain scenarios cause causecode text description 1001 (maps to isdn code 16) normal clearning normal clearing the call is being cleared by exotel because one of the users involved in the call has requested that the call be cleared (hangup) or we have nothing to execute for the call 1002 (maps to isdn code 21) call rejected call rejected the call is being rejected by exotel this is usually sent when the call was not answered and an explicit hangup was specified in the flow 1003 (maps to ahn code 130) ring timeout ring timeout the call is being cleared by exotel while ringing because of the explicit timeout specified for the leg 1004 (maps to ahn code 131 ) connect timeout connect timeout the call is being cleared by exotel while connecting because of the explicit timeout specified for the leg 1005 call throttled call throttled if a call is throttled by exotel as the number of call requests per minute exceeded the allowed value for your account 1006 call rejected dnd incoming promotional calls are barred due to dnd preference of the user this cause indicates that the incoming calls to the number are blocked due to the dnd preference of the user this cause code is not yet populated in the case of the passthru applet