Security Alert - Avaya MERLIN MAGIX Maintenance And Troubleshooting Manual

SECURITY ALERT:

FRLs, applied to ARS and UDP routes, default CORs for all tie and/or all non-tie tandem
trunks, extensions, and remote access barrier codes are particularly important for
maintaining security in a private network. Before changing FRLs in your system, check with
the coordinating system manager, who should understand the security implications for your
local system and for the private network as a whole.
Changing local FRLs may not work simply because the problem is not on the local system. In this
case, go to Possible Cause 5.
Possible Cause 5: The FRL for the default COR for non-tie trunks (PRI) on the remote system
may be blocking tandem calls. The private network is an all-PRI network.
What to Do: Check with the coordinating system manager so that he or she can determine where
the problem exists. This may involve more than one system, depending upon how your private
network is set up. For example, a call might be routed across the private network in a fashion such
as this:
→
Origin System A System B
In this configuration, the coordinating system manager must check routes and default COR
attributes for Systems B and C.
Check to make sure the calling restriction of the default COR is set to unrestricted. The factory
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setting is outward restricted, which blocks calls across the private network.
Check that the routes voice/data capability is correct for the type of call being made. The
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factory setting is Both, which will support both voice and data calls.
In each intervening system, compare the FRLs assigned to routes for the call with the default
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COR FRL. The route FRL must be equal to or lower than the default COR value or the call is
blocked. The factory setting is 3.
If FRL settings are not the cause, go to Possible Cause 6.
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Possible Cause 6: There may be a numbering conflict in the switch identifiers for the trunks that
carry the call. Within a private network, switch identifiers should be unique and unambiguous. If
they are not, calls may terminate prematurely or continue to route unexpectedly.
What to Do: The coordinating system manager must check system planning Form Non-Local
UDP Administration Form in the Installation Specification and review the switch identifiers for all
systems over which calls travel to reach the destination extension(s). To review a report including
the switch identifiers programmed on your local system, select the Print option on the System
Programming menu and then choose
If the switch identifiers are not correct, the coordinating system manager must see that a
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change is made at one or more non-local systems where the conflict exists. To change the
current switch identifiers at your local system, see "Switch Identifiers" in Chapter 5 of Network
Reference.
→ →
System C Destination System D
Trunk Info
Central Office and Private Network Problems
and .
General
Troubleshooting Guidelines and Preparation
5-15