Implementation of ISDN on the 5ESS Switch

The 5ESS TM digital switching system is designed to efficiently meet a multiplicity of applications over a full range of office sizes, and with a wide variety of customized services. The modular architecture and the modular feature customization capability of the 5ESS Switch are the means of achieving this flexibility, and form the base for the addition of integrated services digital network (ISDN) capabilities. As a step in the evolution of universal information services, the 5ESS Switch ISDN capabilities will support a comprehensive set of new voice and data services. The key elements of the 5ESS Switch ISDN implementation are integrated voice/data subscriber access, packet switching, and message signaling. This paper describes the 5ESS Switch architecture and its ISDN implementation, and discusses the advanced business services and operator services that will be built on the ISDN capabilities.