C    ATM Cause Codes

This appendix lists ATM cause and diagnostic codes, their message strings, and brief descriptions that are displayed by various parts of the ATM subsystem. These codes are returned when an ATM request is rejected or when a connection is released.

The User-Network Interface (UNI) cause codes are defined by ATM Forum specifications, and represent error information provided by the ATM network.

1: Unallocated number

The called party cannot be reached because the number (in valid format) is not currently assigned.

2: No route to network

The equipment that sent this cause has received a request to route the call through an unrecognized network. The equipment does not recognize the network either because the network does not exist or because the network exists, but does not serve the equipment that is sending this cause.

Support for this cause varies from network to network.

3: No route to destination

The called party cannot be reached because the network through which the call has been routed does not serve the destination.

Support for this cause varies from network to network.

10: VCI/VPI unacceptable (UNI 3.0 only)

The virtual channel most recently identified is not acceptable to the sending entity for use in this call.

16: Normal VC release

One of the users involved in the call has requested that the call be cleared. In normal situations, the network is not the source of this cause.

17: User busy

The called party is unable to accept another call because the user busy condition has been encountered. Either the called user or the network might generate this cause.

18: No user responding

The called party did not respond to a call establishment message with a connect indication within the prescribed period of time.

21: Call rejected

The equipment that is sending this cause does not want to accept this call. The equipment is neither busy or incompatible.

22: Number changed

The called party number indicated by the calling user is no longer assigned. The new called party number might be included in the diagnostic field. If a network does not support this capability, cause 1 (unallocated number) is used. This cause is returned to a calling party.

23: User rejects all calls with line identification restriction

The call is offered without calling party number information, and the called party requires this information.

27: Destination out of order

The destination by the user cannot be reached because the interface to the destination is not functioning correctly. This indicates that a signaling message could not be delivered to the remote user either because of a physical layer or SAAL failure at the remote user or because user equipment is off-line.

28: invalid number format

The called user cannot be reached because the called party number is not in a valid format or is not complete.

30: Response to ENQUERY

An entity is sending STATUS message in response to a STATUS ENQUERY message. The cause number is included in the STATUS message.

31: Normal release, unspecified cause

A normal event occurred for which no other cause applies.

35: Requested VC unavailable

The requested VPCI/VCI is not available.

36: VPCI/VCI assignment failure

The VPCI/VCI could not be assigned.

37: User cell rate unavail

The requested ATM Traffic Descriptor is unobtainable.

38: Network out of order

The network is not functioning properly. This condition might last a long period of time; any immediate call attempt is likely to fail.

41: Temporary failure

The network is not functioning properly. This condition is temporary; you can retry the call immediately.

43: Access info discarded

The network could not deliver access information (for example, ATM adaptation layer parameters, broadband low layer information, broadband high layer information, and sub-address) to the remote user as requested.

45: No VC available

There is no VC available to handle the call.

47: Resource unavailable

The requested resource is unavailable. No other cause is applicable.

49: QOS unavailable

The requested Quality of Service (QoS) cannot be provided.

51: User cell rate unavailable (UNI 3.0 only)

The requested ATM Traffic Descriptor is unobtainable.

57: Bearer capability not authorized

The user requested a bearer capability that is implemented in the equipment, but the user is not authorized to use.

58: Bearer capability not presently available

The user requested a bearer capability that is implemented in the equipment, but is unavailable at this time.

63: Option not available

The option is unavailable. No other cause applies.

65: Bearer capability not implemented

The equipment that sent this cause does not support the bearer capability requested.

73: Unsupported combination of traffic parameters

The combination of traffic parameters contained in the ATM traffic descriptor information element (IE) is not supported.

78: AAL parameters can not be supported

The equipment that sent this cause received a request to establish a call with ATM adaptation layer parameters that cannot be accommodated.

81: Invalid call reference value

The equipment that sent this cause received a message with a call reference that is not currently in use on the user-network interface (UNI).

82: Identified channel does not exist

The equipment that sent this cause received a request to use a channel that is not activated on the interface for a call.

88: Incompatible destination

The equipment that sent this cause received a request to establish a call that it cannot accommodate. Possible incompatibility reasons include broadband low layer information, broadband high layer information, or compatibility attributes.

89: Invalid endpoint reference

The equipment that sent this cause received a message with an endpoint reference that is not currently in use on the UNI.

91: Invalid transit network selection

A received transit network identification has an incorrect format.

92: Too many pending add party requests

The calling party sent an add party message, but the network is unable to accept another add party message because the network's queues are full. This is a temporary condition.

93: AAL parameters can not be supported (UNI 3.0 only)

The equipment that sent this cause received a request to establish a call that it cannot accommodate. The main reason is the ATM adaptation layer parameters.

96: Mandatory information element missing

The equipment that sent this cause received a message that is missing a required IE.

97: Message type non-existent or not implemented

The equipment that sent this cause received a message with an unrecognized message type. Possible reasons include the message type is undefined or the message is defined, but not implemented by the equipment.

99: IE non-existent or not implemented

The equipment that sent this cause received a message that includes an unrecognized IE or IEs. Possible reasons include the IE is undefined or the IE is defined, but not implemented by the equipment. The IE or IEs were discarded. However, the message was processed because the IE or IEs were not required.

100: Invalid IE contents

The equipment that sent this cause received a valid IE, but the implementation prevents it from understanding the format of one or more fields in the IE.

101: Message not compatible with call state

A received message is incompatible with the call state.

102: Recovery timer expired

A timer expired and an error handling procedure is initiated.

104: incorrect message length

An inconsistent message length occurred.

111: Protocol error unspecified

A protocol error event occurred. No other cause applies.