Advanced Services Based on Integrated Services Digital Network (ISDN)

New telecommunications equipment based on the Integrated Services Digital Network (ISDN) standards is allowing the introduction of many advanced subscriber features. These standards define an interface between subscriber premises equipment and exchange equipment with greatly increased capabilities over the previous analogue interconnections. Telecommunications equipment designers are using this increased capability to provide new services and to tmprove existing services. This paper describes a number of these services from the point of view of the subscriber and discusses the value to him or her. It also discusses how the capabilities achieved with the introduction of the ISDN protocols make these advanced services possible.