Experimental Multiple-Channel Circuit-Switched Communications

A research model of a system for multiple-channel subrate circuit-switched digital communications is described. Three Components of a local communications system (residential or business) are the switching machine, the line, and the user's equipment. Each is briefly described and overall system operation is presented. The user's communications controller, which interfaces the digital line to the user's "devices," is described in detail. The hypothetical user is allowed a multiplicity of devices, each running at a different data rate and connected to a different "party" through the switch. Any device may itself be subclassified into a multiplicity of "virtual" devices, each with a potentially different switched connection. Research objectives include the optimal utilization of system resources, a high degree of user programmability, a friendly interface to the user (or at least a test-bed for developing one), a high degree Of system flexibility so that a variety of implementations can be tested, and a test-bed for experimental services.