Lucent Technologies MERLIN LEGEND Release 7.0 Feature Reference page 764

MERLIN LEGEND Communications System Release 7.0
Feature Reference 555-670-110
Features
Tandem Switching
where the calls are connected to the public switched telephone network. It
includes the following two topics:
Local Calls Routed to Other Systems. This topic explains the factors that
you must consider when you set up your local system so that your users
can make ARS calls via public switched telephone network trunks
connected to another networked system.
Network Calls Routed via the Local System. This topic explains the
factors that you must consider when remote users, calling via ARS from a
networked system, use public switched telephone network facilities
connected to your own local system and/or have calls routed through your
system to another system where they are sent to the PSTN.
''Automatic Route Selection'' on page 77
provide additional general information about these features.
Local Calls Routed to Other Systems
Local system users may use ARS to route calls over tandem trunks to the PSTN
facilities connected to a non-local system.
This arrangement can provide toll cost savings when users need to reach outside
numbers that are not in their own local calling area but are local to other systems
in a network. It also means that in some cases, a MERLIN LEGEND
Communications System may have only one or two PSTN trunks connected to it
for emergency purposes only. Under normal circumstances, the system uses
PSTN facilities connected to another system in the network, which can provide
call-volume advantages when buying PSTN services such as domestic long-
distance calling.
NOTE:
For intersystem calls among network extensions and for routing of DID and
PRI dial-plan routed calls that are sent across the network, UDP routing is
used. It is much like ARS routing, only simpler. Details are provided in
''Uniform Dial Plan Features'' on page
To accommodate certain types of calls, enhance security, and make system
programming simpler, the systems in a network should all use the same ARS
access code. This code then cannot be included in the non-local dial plan of any
networked system, because system programming of the local ARS access code
into the non-local dial plan is blocked. If ARS access codes are not all the same,
great care must be taken not to program a non-local ARS access code into the
non-local dial plan. For example, if the ARS access code is 9, extension ranges
such as 9000–9050 should not be programmed. Programming the ARS access
code into the non-local dial plan can allow inadvertent access to ARS on a remote
system.
and ''Remote Access'' on page 602
741.
Issue 1
April 1999
704