6-8
MAX Administration Guide
Administering ISDN
Understanding ISDN cause codes
32
Outgoing calls barred. (Outgoing call not possible because of access
restriction that has been installed.)
33
User access busy. (If the total made up of the number of free B chan-
nels and the number of calling procedures without any defined B
channel is equal to four, any new incoming calls will be rejected
from within the network. The calling party receives a DISC with a
cause
user access busy
, which indicates the first busy
instance, and a busy signal.)
34
Negative CUG comparison. (Link not possible because of negative
CUG comparison.)
35
Nonexistent CUG. (This CUG does not exist.)
37
Communication as semipermanent link not permitted.
48 - 50
Not used. (Link not possible because, for example, RFNR check is
negative.)
53
Destination not obtainable. (Link cannot be established in the net-
work because of incorrect destination address, services, or facilities.)
56
Number changed. (Number of B subscriber has changed.)
57
Out of order. (Remote TE not ready.)
58
No user responding. (No TE has responded to the incoming SETUP
or call has been interrupted, absence assumed—expiration of call
timeout T3AA.)
59
User busy. (B subscriber busy)
61
Incoming calls barred. (B subscriber has installed restrictions against
incoming link, or the requested service, not supported by the B sub-
scriber)
62
Call rejected. (To A subscriber: Link request actively rejected by
B subscriber, by sending a DISC in response to an incoming SETUP.
To a TE during the phase in which an incoming call is being estab-
lished: The call has already been accepted by another TE on the bus.)
89
Network congestion. (Bottleneck situation in the network; for exam-
ple, all-trunks-busy, no conference set free.)
90
Remote user initiated. (Rejected or cleared down by remote user or
exchange.)
Table 6-2. ISDN cause codes for 1TR6 switch type (continued)
1TR6
Code
Cause
