Patent ID: 8295870

Claim:
A communication system for calling a plurality of terminal devices in response to a single request of call connection, assigning, for a single terminal device which answered the call, a communication band to be occupied in a communication band which can be used, and establishing the call connection in the assigned communication band, the communication system comprising: a first deriving section that derives a communication band required for the call connection of each of the terminal devices to be called when the request of call connection is received; a securing section that secures a communication band having the maximum width in each of the derived communication bands in the communication band which can be used; and an assigning section that assigns a communication band to be occupied in the secured communication band to the terminal device which answered the call, wherein the communication system is constituted such that it establishes the call connection in a set form of connection, the communication system further comprising: a wired communication section and a wireless communication section; a detection section that detects a form of connection specified by the request of call connection; a determination section that determines a wired communication band to be used for communication in a wired section of the call connection based on regulation according to the detected form of connection; and a second deriving section that derives predicted values of speed of communication in the wireless communication section with a plurality of terminal devices to be call targets at the time of a call connection establishment; wherein the first deriving section is constituted such that it derives a communication band required for the call connection with each of the terminal devices based on the wired communication band and the derived predicted value of the speed of communication, using an equation: Band occupying rate=control band+(wired communication band/wireless communication speed)×constant.