Nortel Networks Remote Gateway 50 - Manual (Page 132)

Page 132 of 258 Alternative Call Routing for Network Bandwidth Management
553-3001-207 Standard 2.00 January 2006
4 The main office determines the RLI and uses a DMI to change the dialed
number into a PSTN/MCDN format number.
5 The call is routed over the PSTN/MCDN to the telephone at the branch
office.
With the ALTPrefix digits inserted, the resulting number must be one that
CDP or VNR software can process as a steering code.
Note: For SRGs, the main office manipulates the digits in the call into a
format appropriate for routing from the SRG on PSTN/MCDN trunks.
For more information on SRG, refer to Main Office Configuration for
SRG 505 (553-3001-207).
The steering code allows the call to be translated and referenced to a Route
List Index from which the system chooses the alternate route. The digit
manipulation capability of CDP allows digits (such as the ALTPrefix) to be
deleted and it can insert digits so the resulting number is appropriate for the
alternate route choice selected (PSTN or MCDN). For example, you can
manipulate the digits for PSTN routes so that DID destinations are dialable.
Dialing plans
Consider the many ways that calls can be dialed in a network. A
station-to-station call can be dialed using the following:
• Directory Number (DN)
• Coordinated Dialing Plan DN (starting with a Local Steering Code or
Distant Steering Code)
• Uniform Dialing Plan DN (starting with a Location Code or Home
Location Code)
• Transferable DN (TNDN) or Group Dialing Plan DN
Main offices and branch offices must be able to translate the calls, after the
ALTPrefix is inserted, using CDP or VNR. Take into account the format of
the calls with an ALTPrefix inserted prior to the rest of the digits.