CCITT Activity on signal processing for integrated services digital networks

This paper gives a snapshot of the international activity on standards to be set for speech, sound and picture signals processing for application in the emerging Integrated Services Digital Networks (ISDN). The ISDN is a focal point for the ongoing activity of the CCITT (International Telegraph and Telephone Consultative Committee). ISDNs are conceived as networks which have evolved from the basic digital telephone networks and they will provide end-to-end digital connectivity to support a wide range of services including voice, data, sound and video applications. The CCITT forum has represented, in past years, a driving force for digital equipment and network development. Today, the CCITT standardization role is of increasing importance in view of the rapid advances in digital communication technology, and the expected world-wide development of new communication services. After giving a general outline of the emerging network scenarios for digital communication, the paper concentrates on two aspects: (i) current status of standards for digital speech, sound and video communication; (ii) current activity plans for the evolution of such standards and perspectives for results achievable during the present CCITT study period.