COMMUNICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To identify terminal equipment by means of recognizing an originating sub-address in the case of call incoming in a center device by setting the self sub-address of terminal equipment to a value which is not superimposed in a system. SOLUTION: Terminal equipment 2A originates a call to the center device by transmitting a 'call setting' message without including an 'originating sub- address' information element when it is connected to an ISDN line 3 and requests call originating from an external input terminal after setting the telephone number of the center device 1. Then the sub-address of the unique value which is not superimposed in the system set by the center device 1 is stored in respective kinds of terminal equipment 2. Therefore, in communication after that, the center device 1 can identify terminal equipment and execute communication only by comparing an 'originating sub-address' information request included in the received 'call setting' message with the sub-address which is set in each terminal equipment 2 and recognizing it.