The first 5ESS(R) switch was deployed in 1982 in Seneca, Illinois, ini
tiating the global presence of AT&T digital switching equipment around
the world. Today, the 5ESS switch is an integral part of the telecomm
unication networks in more than 50 countries. From the beginning, the
switch was designed to have a flexible and evolvable architecture, And
for more than a decade, it has continued to meet varied and ever-chan
ging customer needs. The 5ESS-2000 platform is one of the switch's mos
t recent and significant evolutions. This platform not only supports t
oday's service needs, it also accommodates future applications requiri
ng enhanced processing capacity, performance, reliability, and OAM&P (
operations, administration, maintenance, and provisioning). This paper
outlines the switch's current state of requirement, including its arc
hitecture and quality improvements. Hardware and software enhancements
are discussed, as is the system integration and verification philosop
hy used in reducing the product-realization interval. The paper also r
eports on quality and performance data from customer field application
s that have deployed the 5ESS-2000 platform.