IP-Centrex System : Nortel Networks

Nortel Networks is the world's largest vendor of Centrex systems and has been responsible for most of the development of these services outside North America over the past decade. There are nearly 100 million lines on Nortel's DMS switches worldwide and of these well over 10 million are for Centrex. Nortel has announced a family of softswitches under the name of Succession, based on Sun computing platforms. The CS2000 can process 300,000 BHCA with a pair of servers, supporting both asynchronous transfer mode (ATM) and IP, together with H.323 and SIP standards. Nortel's concept of IP-Centrex, delivered either from a legacy DMS switch through gateways and from the CS2000 softswitch, is illustrated in Figure 4.


Figure 4: Centrex IP for extended service reach. (Reproduced with the permission of Nortel Networks. Copyright © 2002 Nortel Networks, All rights reserved.)

Nortel Networks conducted a number of IP-Centrex technology trials in North America and Europe during 2001 and 2002. Then, in late 2001, Telstra announced that it would offer CustomNet IP in the major cities of Australia, using Nortel-made gateways to link IP-based endpoints to the existing CustomNet (i.e., digital Centrex) service. Telstra stated that CustomNet IP would also use data services, such as dial connect, cable, asynchronous digital subscriber line (ADSL), or ATM, to provide access to its DMS-based CustomNet. This is the first product set to be released under Telstra's Next Generation Telephony project, but the actual start-up date for this service was not announced.