Nortel Networks SRG 50 NN43001-307 - Manual (Page 173)

Description 173
3. The Call Server inserts the ALTPrefix configured for the BO2 zone prior
to IP Phone F’s telephone number, dialed by the user.
Example: ALTPrefix assigned is 222. The dialed number becomes 222
6020.
4. The call is routed to the virtual trunk by CDP or VNR. The virtual trunk
sends a request to the NRS for address resolution. The digit string sent
to the NRS contains the ALTPrefix. The NRS returns the IP address of
the branch office endpoint to the virtual trunk.
5. The virtual trunk places the call to the branch office.
The branch office receives the call and recognizes the first part of the
number as a Steering Code. The call is steered to an RLI. The DMI
manipulates the number into a PSTN number and the branch office
outpulses the digits to the Central Office (CO) serving the branch office.
(This may be the same CO as the one serving the main office.) If the
alternate route has MCDN trunks in the BO2 zone, the call is outpulsed
on one of these trunks, after the branch office uses Digit Manipulation
(action labeled 2 in
Figure 70 "Call between a branch office telephone
and another branch office telephone" (page 171) ).
Example: The digit string 2226 is programmed as a Distant Steering
Code (DSC) at the branch office. Calls starting with this DSC are
handled by an RLI with PSTN trunks as an entry. If the Public format
number for the destination telephone is a DID number, then the Digit
Manipulation Index associated with the PSTN route must:
• delete 3 digits (remove the ALTPrefix 222)
• insert 1506348 (in order to compose the DID number of the
destination telephone, which is 15063486020)
6. The call comes into IP Phone F from the PSTN in the BO1 zone (action
labeled 3 in Figure 70 "Call between a branch office telephone and
another branch office telephone" (page 171) ).
Alternative Call Routing for NBWM feature used in All Calls mode
The situations illustrated in Figure 66 "Call between a branch office
telephone in Normal Mode and a main office telephone" (page 164) , Figure
68 "Call between a main office telephone and a branch office telephone"
(page 168)
, and Figure 70 "Call between a branch office telephone and
another branch office telephone" (page 171) can also apply to the operation
of the feature when it is active all the time, regardless of available bandwidth.
For an example of this, the information below applies to Figure 66 "Call
between a branch office telephone in Normal Mode and a main office
telephone" (page 164)
when all calls are alternately routed.
Nortel Communication Server 1000
Main Office Configuration Guide for SRG 50
NN43001-307 02.02 Standard
Release 5.0 3 December 2007
Copyright © 2005-2007, Nortel Networks
.