Part of understanding issues, it's been able to acknowledge their reason. As part of expanding current https://supportforums.cisco.com/docs/DOC-2759, which in terms of the alarm discussed below, it explains some of the reasons and most common workarounds, I have come to answer a recurrent need for: "Route List Exhausted" Cause List. So you come into your office and find the following alarm either on RTMT or on your Inbox: There are X RouteListExhausted events (up to 30) received during the monitoring interval From Day Month Day XX:XX:XX Timezone Year to Day Month Day XX:XX:XX Timezone Year : RouteListName : Route List Name, Reason=XX, RouteGroups(XXX:XXX)AppID : Cisco CallManagerClusterID : StandAloneClusterNodeID : XXXXXTimeStamp : Day Month Day XX:XX:XX Timezone Year Now what do you do? Well yes, best is to check first document reference at the beginning. However to grasp a reason we need to understand this last one its mapped to a Q.931 ISDN cause from whatever protocol the Route List contains. This means that if you have a SIP trunk on that Route List, and you get a rejection from the SIP trunk as cause 603 which means it was "Declined", the route list will map this to the ISDN causes and report a Reason 21 "Call Rejected". Having the above in mind, here is a list of Reason's for ISDN to map this alerts: Cause    No. 0 This is usually given by the router when none of the other codes apply. This    cause usually occurs in the same type of situations as cause 1, cause 88, and    cause 100. Cause No. l - Unallocated (unassigned) number. This cause indicates that the destination requested by the calling  user cannot be reached because, although the number is in a valid  format, it is not currently assigned (allocated). What it usually means: The SPIDS may be incorrectly entered in the router or the Telco switch, giving a SPID failure in the router logs. The ISDN phone number being dialed by the router is invalid and  the telco switch cannot locate the number to complete the call, as it is  invalid. On long distance calls, the call cannot be properly routed to its destination. Cause No. 2 - No route to specified transit network (national use). This cause indicates that the equipment sending this cause has  received a request to route the call through a particular transit  network which it does not recognize. The equipment sending this cause  does not recognize the transit network either because the transit  network does not exist or because that particular transit network not  serve the equipment which is sending this cause. Cause No. 3 - 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. Cause No. 4 - 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. Cause No. 5 - misdialed trunk prefix (national use). This cause indicates the erroneous inclusion of a trunk prefix in the called    party number. This number is to sniped from the dialed number being sent to    the network by the customer premises equipment. Cause No. 6 - channel unacceptable. This cause indicates that the channel most recently identified is not acceptable to the sending entity for use in this call. Cause No. 7 - 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). Cause No. 8 - preemption. This cause indicates the call is being preempted. Cause No. 9 - 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. Cause No. 16 - 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.What it means: This could be almost anything; it is the vaguest of the cause codes. The call  comes down normally, but the reasons for it could be:   Bad username or password Router's settings do not match what is expected by the remote end. Telephone line problems. Hung session on remote end. Cause No. 17 - user busy. This cause is used to indicate that the called party is unable to  accept another call because the user 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.What is means: Calling end is busy. Cause No. 18 - 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.What it means: The equipment on the other end does not answer the call. Usually this is a misconfiguration on the equipment being called. Cause No. 19 - no answer from user (user alerted). 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. Cause No. 20 - 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. Cause No. 21 - 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  reason for rejection.What it means: This is usually a telco issue. The call never reaches the final  destination, which can be caused by a bad switch translation, or a  misconfiguration on the equipment being called. Cause No. 22 - 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. Cause No. 26 - non-selected user clearing. This cause indicates that the user has not been awarded the incoming call. Cause No. 27 - 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. Cause No. 28 - invalid number format (address incomplete). 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. Cause No. 29 - facilities rejected. This cause is returned when a supplementary service requested by the user cannot be provide by the network. Cause No. 30 - 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. Cause No. 31 - normal. unspecified. This cause is used to report a normal event only when no other cause in the    normal class applies. Cause No. 34 - no circuit/channel available. This cause indicates that there is no appropriate circuit/channel presently    available to handle the call.What it means: There is no place on the Public Telephone network to place the call; the call  never gets to its destiation. This is usually a temporary problem. Cause No. 35 - Call Queued. Cause No. 38 - 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. Cause No. 39 - 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) Cause No. 40 - 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. Cause No. 41 - temporary failure. This cause indicates that the network is not functioning correctly and that    the condition is no likely to last a long period of time; e.g., the user may    wish to try another call attempt almost immediately.What it means: This means that there is a temporary failure at the physical layer on the ISDN  network. If you remove the ISDN cable from the Netopia, you would see this. It's usually temporary. Cause No. 42 - switching equipment congestion. This cause indicates that the switching equipment generating this cause is experiencing a period of high traffic.What it means: Just too much going on at this point on the ISDN network to get the call through to its destination. Cause No. 43 - 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. Cause No. 44 - 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. Cause No. 46 - precedence call blocked. This cause indicates that there are no predictable circuits or that  the called user is busy with a call of equal or higher preventable  level. Cause No. 47 - resource unavailable, unspecified. This cause is used to report a resource unavailable event only when no other    cause in the resource unavailable class applies. Cause No. 49 - Quality of Service not available. This cause is used to report that the requested Quality of Service, as  defined in Recommendation X.213. cannot be provided (e.g., throughput  of transit delay    cannot be supported). Cause No. 50 - 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.What it means: 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. Cause No. 52 - outgoing calls barred. Cause No. 53 - 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. Cause No. 54 - incoming calls barred Cause No. 55 - 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. Cause No. 57 - 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. Cause No. 58 - bearer capability 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. Cause No. 62 - inconsistency in outgoing information element. This cause indicates an inconsistency in the designated outgoing access information and subscriber class. Cause No. 63 - 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. Cause No. 65 - 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. Cause No. 66 - channel type not implemented. This cause indicates that the equipment sending this cause does not support    the channel type requested. Cause No. 69 - requested facility not implemented. This cause indicates that the equipment sending this cause does not support    the requested supplementary services. Cause No. 70 - 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. Cause No. 79 - 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. Cause No. 81 - invalid call reference value. This cause indicates that the equipment sending this cause has  received a message with a call reference which is not currently in use  on the user-network interface. Cause No. 82 - 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. Cause No. 83 - a suspended call exists, but this call identify does not. This cause indicates that a call resume has been attempted with a call  identity which differs from that in use for any presently suspended  call(s). Cause No. 84 - 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) which is  already in use for a suspended call within the domain of interfaces  over which the call might be resumed. Cause No. 85 - 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. Cause No. 86 - 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). Cause No. 87 - 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. Cause No. 88 - incompatible destination. This cause indicates that the equipment sending this cause has  received a request to establish a call which has low layer  compatibility. high layer compatibility or other compatibility  attributes (e.g., data rate) which cannot be accommodated.What it means:  This usually means that the Number To Dial in the Connection  Profile is in the wrong format. You may need to dial a 10 or 11 digit  number, or dial a 9 in front of the number if it is a Centrex line. This problem may also give a Cause 111. Dialing at the wrong line speed can also give this Cause. Cause No. 90 - non-existent CUG. This cause indicates that the specified CUG does not exist. Cause No. 91 - invalid transit network selection (national use). This cause indicates that a transit network identification was received which    is of an incorrect format as defined in Annex C/Q.931 Cause No. 95 - invalid message, unspecified. This cause is used to report an invalid message event only when no other cause in the invalid message class applies. Cause No. 96 - mandatory information element is missing. This cause indicates that the equipment sending this cause has  received a message which is missing an information element which must be  present in the message before that message can be processed. What it means: This is rarely seen in North America but usually means that the number  that is  being dialed is in the wrong format, (similar to cause 88). Some part of  the format being used is not understood by either the remote side  equipment or the switching equipment between the source and destination  of the call. Cause No. 97 - 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. Cause No. 98 - 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. Cause No. 99 - 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. Cause No. 100 - Invalid information element contents. This cause indicates that the equipment sending this cause has  received and    information element which it has implemented; however, one or more of  the fields in the information element are coded in such a way which has  not been implemented by the equipment sending this cause. What it means: Like cause 1 and cause 88, this usually indicates that the ISDN number  being dialed is in a format that is not understood by the equipment  processing the call. SPIDs will sometimes fail to initialize with a  Cause 100, or a call will fail with this cause. Cause No. 101 - message not compatible with call state. This cause indicates that a message has been received which is incompatible    with the call state. Cause No. 102 - 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. What it means: This is seen in situations where ACO (Alternate Call Offering) is being  used.  With this type of call pre-emption, the Telco switch operates a timer.  For example, when an analog call is placed to a Netopia router that has  two B Data Channels in place, the router relinquishes the second  channel, but if it doesn't happen in the time allotted by the switch  programming, the call will not ring through and will be discarded by the  switch. Cause No. 103 - parameter non-existent or not implemented - passed on (national use). 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. Cause No. 110 - 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. Cause No. 111 - protocol error, unspecified. This cause is used to report a protocol error event only when no other cause    in the protocol error class applies. Cause No. 127 - Intel-working, unspecified. This cause indicates that an interworking call (usually a call to 5W56 service) has ended. Notes about Cause Codes over 128 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. The PRI equipment vendors are the most likely to use these codes as  they have    been using proprietary messages in the facilities data link for some  time now    (there is an as yet undefined area in the FDL which is big enough to  carry small datagrams or messages). It is typically used to pass  proprietary control or    maintenance messages between multiplexers. Additional Sources: http://en.wikipedia.org/wiki/Q.931 http://www.cisco.com/en/US/docs/voice_ip_comm/bts/3.5/command/reference/992M.html http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/err_msgs/8_x/ccmalarms801.html http://www.cisco.com/en/US/tech/tk801/tk379/technologies_tech_note09186a008012e95f.shtml Special thanks to Robert Thomas. Please rate if you find this useful and feel free to share any modifications needed.     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.     Cause No. 4 - 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.     Cause No. 5 - misdialed trunk prefix (national use).     This cause indicates the erroneous inclusion of a trunk prefix in the called    party number. This number is to sniped from the dialed number being sent to    the network by the customer premises equipment.     Cause No. 6 - channel unacceptable.     This cause indicates that the channel most recently identified is not acceptable to the sending entity for use in this call.     Cause No. 7 - 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).     Cause No. 8 - preemption.     This cause indicates the call is being preempted.     Cause No. 9 - 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.     Cause No. 16 - 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.     What it means:     This could be almost anything; it is the vaguest of the cause codes. The call  comes down normally, but the reasons for it could be:         Bad username or password         Router's settings do not match what is expected by the remote end.         Telephone line problems.         Hung session on remote end.     Cause No. 17 - user busy.     This cause is used to indicate that the called party is unable to  accept another call because the user 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.     What is means:     Calling end is busy.     Cause No. 18 - 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.     What it means:     The equipment on the other end does not answer the call. Usually this is a misconfiguration on the equipment being called.     Cause No. 19 - no answer from user (user alerted).     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.     Cause No. 20 - 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.     Cause No. 21 - 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  reason for rejection.     What it means:     This is usually a telco issue. The call never reaches the final  destination, which can be caused by a bad switch translation, or a  misconfiguration on the equipment being called.     Cause No. 22 - 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.     Cause No. 26 - non-selected user clearing.     This cause indicates that the user has not been awarded the incoming call.     Cause No. 27 - 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.     Cause No. 28 - invalid number format (address incomplete).     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.     Cause No. 29 - facilities rejected.     This cause is returned when a supplementary service requested by the user cannot be provide by the network.     Cause No. 30 - 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.     Cause No. 31 - normal. unspecified.     This cause is used to report a normal event only when no other cause in the    normal class applies.     Cause No. 34 - no circuit/channel available.     This cause indicates that there is no appropriate circuit/channel presently    available to handle the call.     What it means:     There is no place on the Public Telephone network to place the call; the call  never gets to its destiation. This is usually a temporary problem.     Cause No. 35 - Call Queued.     Cause No. 38 - 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.     Cause No. 39 - 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)     Cause No. 40 - 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.     Cause No. 41 - temporary failure.     This cause indicates that the network is not functioning correctly and that    the condition is no likely to last a long period of time; e.g., the user may    wish to try another call attempt almost immediately.     What it means:     This means that there is a temporary failure at the physical layer on the ISDN  network. If you remove the ISDN cable from the Netopia, you would see this. It's usually temporary.     Cause No. 42 - switching equipment congestion.     This cause indicates that the switching equipment generating this cause is experiencing a period of high traffic.     What it means:     Just too much going on at this point on the ISDN network to get the call through to its destination.     Cause No. 43 - 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.     Cause No. 44 - 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.     Cause No. 46 - precedence call blocked.     This cause indicates that there are no predictable circuits or that  the called user is busy with a call of equal or higher preventable  level.     Cause No. 47 - resource unavailable, unspecified.     This cause is used to report a resource unavailable event only when no other    cause in the resource unavailable class applies.     Cause No. 49 - Quality of Service not available.     This cause is used to report that the requested Quality of Service, as  defined in Recommendation X.213. cannot be provided (e.g., throughput  of transit delay    cannot be supported).     Cause No. 50 - 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.     What it means:     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.     Cause No. 52 - outgoing calls barred.     Cause No. 53 - 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.     Cause No. 54 - incoming calls barred     Cause No. 55 - 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.     Cause No. 57 - 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.     Cause No. 58 - bearer capability 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.     Cause No. 62 - inconsistency in outgoing information element.     This cause indicates an inconsistency in the designated outgoing access information and subscriber class.     Cause No. 63 - 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.     Cause No. 65 - 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.     Cause No. 66 - channel type not implemented.     This cause indicates that the equipment sending this cause does not support    the channel type requested.     Cause No. 69 - requested facility not implemented.     This cause indicates that the equipment sending this cause does not support    the requested supplementary services.     Cause No. 70 - 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.     Cause No. 79 - 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.     Cause No. 81 - invalid call reference value.     This cause indicates that the equipment sending this cause has  received a message with a call reference which is not currently in use  on the user-network interface.     Cause No. 82 - 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.     Cause No. 83 - a suspended call exists, but this call identify does not. This cause indicates that a call resume has been attempted with a call  identity which differs from that in use for any presently suspended  call(s).     Cause No. 84 - 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) which is  already in use for a suspended call within the domain of interfaces  over which the call might be resumed.     Cause No. 85 - 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.     Cause No. 86 - 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).     Cause No. 87 - 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.     Cause No. 88 - incompatible destination.     This cause indicates that the equipment sending this cause has  received a request to establish a call which has low layer  compatibility. high layer compatibility or other compatibility  attributes (e.g., data rate) which cannot be accommodated.     What it means:         This usually means that the Number To Dial in the Connection  Profile is in the wrong format. You may need to dial a 10 or 11 digit  number, or dial a 9 in front of the number if it is a Centrex line.         This problem may also give a Cause 111.         Dialing at the wrong line speed can also give this Cause.     Cause No. 90 - non-existent CUG.     This cause indicates that the specified CUG does not exist.     Cause No. 91 - invalid transit network selection (national use).     This cause indicates that a transit network identification was received which    is of an incorrect format as defined in Annex C/Q.931     Cause No. 95 - invalid message, unspecified.     This cause is used to report an invalid message event only when no other cause in the invalid message class applies.     Cause No. 96 - mandatory information element is missing.     This cause indicates that the equipment sending this cause has  received a message which is missing an information element which must be  present in the message before that message can be processed.     What it means:     This is rarely seen in North America but usually means that the number  that is  being dialed is in the wrong format, (similar to cause 88). Some part of  the format being used is not understood by either the remote side  equipment or the switching equipment between the source and destination  of the call.     Cause No. 97 - 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.     Cause No. 98 - 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.     Cause No. 99 - 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.     Cause No. 100 - Invalid information element contents.     This cause indicates that the equipment sending this cause has  received and    information element which it has implemented; however, one or more of  the fields in the information element are coded in such a way which has  not been implemented by the equipment sending this cause.     What it means:     Like cause 1 and cause 88, this usually indicates that the ISDN number  being dialed is in a format that is not understood by the equipment  processing the call. SPIDs will sometimes fail to initialize with a  Cause 100, or a call will fail with this cause.     Cause No. 101 - message not compatible with call state.     This cause indicates that a message has been received which is incompatible    with the call state.     Cause No. 102 - 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.     What it means:     This is seen in situations where ACO (Alternate Call Offering) is being  used.  With this type of call pre-emption, the Telco switch operates a timer.  For example, when an analog call is placed to a Netopia router that has  two B Data Channels in place, the router relinquishes the second  channel, but if it doesn't happen in the time allotted by the switch  programming, the call will not ring through and will be discarded by the  switch.     Cause No. 103 - parameter non-existent or not implemented - passed on (national use).     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.     Cause No. 110 - 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.     Cause No. 111 - protocol error, unspecified.     This cause is used to report a protocol error event only when no other cause    in the protocol error class applies.     Cause No. 127 - Intel-working, unspecified.     This cause indicates that an interworking call (usually a call to 5W56 service) has ended.     Notes about Cause Codes over 128     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.     The PRI equipment vendors are the most likely to use these codes as  they have    been using proprietary messages in the facilities data link for some  time now    (there is an as yet undefined area in the FDL which is big enough to  carry small datagrams or messages). It is typically used to pass  proprietary control or    maintenance messages between multiplexers. ... View more