| 摘要 |
PROBLEM TO BE SOLVED: To provide a network system capable of housing an information terminal to a line concentrator in a non-contact manner without being involved in the change, etc., of communication protocols. SOLUTION: In this network system, a newly provided repeater 20 is intervened between a portable information terminal 10 and a hub which are directly connected by a cable in the conventional practice, and the terminal 10 and the repeater 20 are respectively provided with optical space transmitting devices 14 and 21 for performing optical communication. And, it is possible to show to the CPU 11 of the terminal 10 and the hub 30 as if they are connected by a cable as in the conventional practice by converting an electric signal into an optical signal between the terminal 10 and the repeater 20, transferring it by a radio channel and then, converting an optical signal into an electric signal again after once converting. It is possible to make the terminal 10 to be housed in the hub 30 in a non-contact manner without being involved in the change, etc., of a communication protocols at all. |
