Technical Aspects of Expanding Voice Channels In The ISDN Basic Rate Interface
A key to the success of the integrated services digital network (ISDN) market is to stimulate customer interest in the services and benefits that the technology can offer. The paper introduces an ISDN basic rate interface (BRI) arrangement so that either a data terminal and two voice terminals, three voice terminals, or four voice terminals can be operated simultaneously through the interface. A dual-bus basic rate interface arrangement and a bit rate adaptation method are used to accommodate the expanding channels. The technical aspects on S/T interface frame formats and the call processing are thoroughly discussed. The study result shows that the standard ISDN S/T interface remains intact. Therefore, this enhanced BRI service does not preclude the traditional 2B+D offering. By adding the expanding voice channels capability to the ISDN basic rate interface, it could further stimulate market demand.