COMMUNICATION CONTROL SYSTEM

摘要

PURPOSE:To obtain a private branch system which uses general purpose terminals, is capable of discriminating an extension transmission and a line wire transmission without inputting a special number before dialing an opposite number and further is capable of connecting between a main equipment and the terminals by bus wirings, etc. CONSTITUTION:A communication control device 101 which is connectable with a line wire 131 connecting with the side of the user/network interface of an ISDN and the user/network interface of the ISDN, is connected in between an extension 132 connecting plural ISDN communication terminal devices 133a to 133c having each sub-address and performs the exchange control of an extension communication and a line wire communication is provided. The incoming number included in the call setting message transmitted from the communication terminal equipment connecting the extensions is read and either one of the extension number and the line wire number is discriminated depending on whether the number is one which is included in the number plan of the line wire number or not. When this incoming number is the extension number, the incoming number in this call setting message is rewritten into an incoming sub-address and this call setting message is transmitted to the side of the extension.