PURPOSE: To provide a communication system without the need of specially providing a switching device provided with a high-level function even in the case of performing multi-media service.
CONSTITUTION: This system is provided with a bi-directional tree network 10, a center unit (high capability exchange) 11 connected to the base end of the tree network, plural terminating devices 12 respectively connected the ends and subscriber terminals 13 respectively housed in the terminating devices. The respective terminating devices are provided with multiplexers 120 for multiplexing information to be transmitted from the subscriber terminals to the side of the center unit and signal selection devices 121 for decoding and selectively receiving only the information for which the subscriber terminal is specified among the information transmitted through the tree network. The center unit is provided with an exchange 11 and a returning device 11b for scrambling the information transmitted from the side of the subscriber terminal so as to make it decodable only by the signal selection device instructed by the exchange and transmitting it back to the side of the tree network.
| JP3883792 | COMMUNICATION SYSTEM |
| WO/2004/049608 | METHODS AND SYSTEMS FOR CONFERENCE CALL BUFFERING |
| JP2005026898 | EMERGENCY CONNECTION SYSTEM FOR IP TELEPHONE SET |
TAKEUCHI YOSHIO
OHASHI MASAYOSHI
MIZUNO TOSHIO
