Data link control method and system for integrated services digital network

摘要

There is a communication system comprising: an integrated services digital network (ISDN) having a plurality of information channels (Bch) and at least one control channel (Dch); a CPU (host computer) connected to said ISDN through a communication control processor (CCP); and a plurality of packet terminals connected to the ISDN. In the communication system, when a call request from the CPU or an incoming call request from one of the packet terminals is input to the CCP, if the B channel data link connection or the D channel data link connection for the packets has already been established between the CCP and the ISDN, the CCP selects the channel data link connection as a channel for communication with the packet terminal and multiplexes a plurality of calls to the same channel even if the other space B channels exist.