Filter
Top Products
82 | Section 6
6.7 ISDN Cause Phrases/Values
When there is an ISDN problem in the network, a phrase appears in the ISDN protocol log
that communicates information about the cause of the trouble. See Section 7.10 for how to
enable ISDN logging through the Telnet port. ese “Cause Values” are numbers generated by
the network. When possible, we use those suggested by the Bellcore standard. Note that in some
cases there may be more than one meaning. is can frequently be evaluated by whether the
message has been received by the calling party or the called party.
CLASS 1.1 (normal)
Cause No. 1 - Check number, redial (unallocated number)
is cause indicates that the called party cannot be reached because, although the called party
number is in a valid format, it is not currently allocated (assigned).
Cause No. 2 - No route to network /Prefix 0 dialed in error
is 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. e equipment sending
this cause does not recognize the transit network either because the transit network does not
exist or because that particular transit network, while it does exist, does not serve the equipment
which is sending this cause.
or
is cause indicates the prefix 0 is invalid for the entered number
Cause No. 3 - No route to dest./Prefix 1 dialed in error
is 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. is cause is supported on a
network-dependent basis.
or
A 1 was dialed when not required. Redial without the 1.
Cause No. 4 – No prefix 1/Special Information Tone
e prefix 1 is not required for this number
or
is 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)
is cause indicates the erroneous inclusion of a trunk prefix in the called party number.
Cause No. 6 – Channel unacceptable
is cause indicates a called user cannot negotiate for a B-channel other than that specified in
the SETUP message.
Cause No. 7 – Call awarded and being delivered on an established channel
is call indicates the user has been awarded the incoming calls, and that call is being connected
to a channel already established to that user for similar calls (e.g. packet-mode, X.25 virtual calls,
etc).