AT&T Switching Systems: An Overview
Morimi Iwama · AT&T Technical Journal · 1994
The state of switching in AT&T reflects the state of the business in telecommunications. Both have been transformed by the effects of globalization, deregulation, the merging of technologies and industries, and the growing demand for customized solutions and rapid response to customer needs. When AT&T installed the first 5ESS® digital switch in 1982, the role of that state-of-the-art system was local switching of voice over wireline loops. Today, the traffic handled by the 5ESS switch includes data, graphic images, and video as well as voice, and the system's role has broadened to include local/toll, operator services, international gateway, intelligent network, and wireless communications applications. Another instance of an industry trend reflected directly in AT&T switching is the GlobeView™ — 2000 Broadband System, the asynchronous transfer mode (ATM) system introduced by AT&T in 1993. ATM embodies the merging of computer and communications technology, and it enables network providers to meet the new demands of converging markets by handling high-quality video, highspeed data, multimedia, and voice on a single platform. This issue of the AT&T Technical Journal, dedicated entirely to switching, provides a snapshot of the state of the art and insight into the state of the business.