divide the local exchange into two functions: local termination and exchange termination. The
local termination function deals with the transmission facility and termination of the local loop.
The exchange termination function deals with the switching portion of the local exchange.
used in North America. The recent release of National ISDN-1 software has corrected most
incompatibility issues between the AT&T and Northern Telecom switches. Prior to the release
of this software, for example, you could not use AT&T ISDN products with a Northern Telecom
switch.
16000 5ESS switches are in use worldwide, serving close to 40 million lines. In the United
States, approximately 85 percent of the BRI lines in service connect to a 5ESS-equipped central
office.
range of telecommunication services. The DMS-100, introduced in 1978, can terminate up to
100,000 lines. Although AT&T and Northern Telecom have deployed the most ISDN switches,
there are other ISDN switch manufacturers. Table 6-2 depicts the various switch types available
for BRI implementations.
of the router.