Lucent Technologies MERLIN LEGEND Release 6.1 Network Reference Manual page 201

MERLIN LEGEND Communications System Release 6.1
Network Reference 555-661-150
5 Network Management
General Programming in Private Networks
"Facility Restriction Levels and Remote Access" on page 5
interactions among FRLs in greater detail. For procedures that allow you to assign
ARS FRLs to extensions, see System Programming.
Remote Access with Barrier Codes
When non-local users access the PSTN facilities connected to your local system
or private network calls are routed through your system, you use this procedure to
specify default COR settings for all tie trunks (that is, all tandem tie trunks, analog
or T1) and/or all non-tie trunks (that is, all tandem PRI trunks). Be sure to specify
that remote access calls on these trunks do require barrier codes.
!
SECURITYlALERT:
Private network systems require special attention to security issues. Follow
the rules below when setting up and planning your system for private
network use.
The barrier code setting is ignored for UDP and ARS calls on tandem trunks, but
applies to remote access calls that arrive from the PSTN on DID, PRI dial-plan
routed, or tandem facilities for those UDP calls that are dialed using a Remote
Access code included in the non-local dial plan. In a private network, these types
of remote access calls should have restrictions applied to barrier codes and
should not be restricted by default COR settings. In addition, barrier codes should
be required for dial-in and dedicated/shared remote-access trunks used by
remote access users on your own system. Do not assign private networked trunks
for dedicated remote access. For programming information, see System
Ensure that barrier codes are required for incoming remote access
calls received on PSTN PRI dial-plan routed and DID facilities, as
well as those calls that are made from the local system by dialing
the Remote Access code (889, for example). When you program the
default COR, turn the barrier code requirement on. This setting is
ignored for ARS calls and calls to non-local extensions across the
private network. However, it is still applied to DID and PRI dial-plan
routed remote access calls as well as to calls received on a tandem
trunk and routed to a Remote Access code. Because the COR
Calling Restriction must be set to unrestricted for private network
calling, using barrier codes on these facilities is essential in order to
apply security measures. When a Remote Access code is included
in the non-local dial plan of the calling system, the caller's barrier
code FRL on the called system is compared to the UDP or ARS
route FRL on the called system. See the Feature Reference and
"Remote Access Default Class-of-Restriction Settings" on page 6
details.
Extension and ARS FRLs should be carefully and stringently
assigned in order to prevent unauthorized trunk-to-trunk transfers to
local PSTN facilities.
this feature in a private network system.
5
Table 4–1, page 4-3
Issue 1
August 1998
Page 5-5
discusses the
explains the operation of
for