INTRODUCTION TO INTEGRATED SERVICES DIGITAL NETWORKS.

There is already a rapidly increasing demand for new subscriber services, for data in particular, and the trend is expected to accelerate. The most likely future solution for providing these services is the ISDN (integrated services digital network). An integrated services digital network will handle telephony and a wide range of services such as videotex, teletex, and facsimile using the same exchanges and transmission paths. The authors outline the main factors that must be considered in the evolution towards the goal of an ISDN.