149Appendix
Appendix
Global Management System User’s Guide
ISDN Cause Codes
Cause CodeCause Description Denition
1 Unassigned number The switch received the sent ISDN number in the correct
format; however, no destination equipment uses the number.
2 No route to specied transit
network
The ISDN exchange cannot recognize the intermediate
network through which to route the call.
3 No route to destination The intermediate network through which the call is routed does
not service the destination address.
6 Channel unacceptable The specied channel does not provide sufcient service
quality to accept the requested connection.
7 Call awarded and delivered The user is assigned an incoming call that is being connected
to an already-established call channel.
16 Normal call clearing Normal call clearing has occurred.
17 User busy All B channels are in use; the called system acknowledges the
connection request, but is unable to accept the call.
18 No user responding The destination does not respond to the call so the connection
cannot be completed.
19 No answer from user (user
alerted)
The destination fails to complete the connection within the
prescribed time after responding to the connection request.
The problem occurs at the remote end of the connection.
21 Call rejected The destination rejects the call for an unknown reason,
although capable of accepting the call.
22 Number changed No system has been assigned the ISDN number used to set
up the call. (The diagnostic eld of the message may return an
alternate address is assigned to the called equipment.)
25 Non-selected user clearing The destination rejected the call, although capable of accepting
it, because the call was not assigned to the user.
27 Destination out of order A signaling message cannot be delivered because the interface
is not functioning correctly, and therefore the destination can
not be reached. This condition might be temporary, though of
extended duration; for instance, remote equipment might be
turned off.
28 Invalid number format Destination address presented in an unrecognizable format or
an incomplete destination address made the connection unable
to be established.