SIGNAL CONVERTER, SERVER, NETWORK INFORMATION SYSTEM, CONTROL METHODS THEREOF AND TELEPHONE TERMINAL

摘要

Since telephone terminals 301, 302 and 303 are used as control terminals in a network information system by using DTMF signals (or packet signals), there is no need for a specially designed terminal or computer system, and any user (or researchee) who has the telephone terminal can respond to a server. In addition, by using a calling function, which is essentially provided to the telephone terminals, when the system is in use, audio communication can be easily established between users.