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.