Lucent Technologies MERLIN LEGEND Release 6.0 Network Reference Manual page 78

MERLIN LEGEND Communications System Release 6.0
Network Reference 555-660-150
2 Call-Handling Scenarios
Network Configuration Scenarios
system for technical support reasons or for changing forwarding options at their
home extensions on remote systems. Users must enter barrier codes in order to
make these remote access calls into the non-local system via the non-local dial
plan. Their barrier code FRLs must permit the remote access calls using the UDP
routes.
Table 2–2, page 2–20
so that users on the other system can access their local PSTN facilities. It also
illustrates how they allow local users to access PSTN facilities on the other
system. Table 2–3, page 2–21
originating in the network systems. As you review the tables, note the following
rules:
Local ARS routing analyzes the initially dialed digits to determine whether a
call can be handled more economically using local or non-local PSTN
lines/trunks.
If a call should be routed over a non-local system for toll-saving purposes,
the local ARS routing directs it to a tandem PRI trunk pool, prepending the
ARS access code. Local PSTN pools are only used as a fallback option,
and more restrictive, higher-numbered FRLs are assigned to these ARS
routes. Voice extensions can use the Automatic or Selective Callback
feature to queue for the first route when other routes are either busy or
unavailable because of FRL restrictions.
Local FRL extension restrictions apply to local ARS calls. If a call is initially
routed over tandem trunks, the FRL for that tandem trunk route is checked
against the call originator's extension FRL. When the non-local system's
ARS feature subsequently analyzes the call for routing, it does not apply its
local FRL restrictions to the network call. However, it compares the FRL for
the local system default COR for non-tie trunks (tandem PRI) with the FRL
assigned to the local ARS route. The default COR FRL is set to 3. The
route FRL must be equal to or lower than 3 in order for the call to go
through.
shows how the system managers set up their local systems
summarizes the key points about routing for calls
NOTE:
Even though the ARS access codes for the two systems match, calls
with area codes defined in ARS that are routed via network trunks
still require prepending of the non-local system's ARS code. The
prepended ARS access code signals the non-local system to handle
the call using ARS.
Issue 1
February 1998
Page 2-18