Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Akio Yao

Yasushi Yokomitsu

Yuji Igata

Masahiro Shigyo

Noriaki Maehara

Yuji Mitsunaga

Toshiyuki Hamasaki

Hiroshi Konishi

Kiminori Washitani

Hideaki Nagao

A power line communication apparatus transmits a signal to a first power line communication apparatus through a power line connecting to a second power line communication apparatus. The power line communication apparatus includes an information retriever for retrieving transmission rate information indicating both a first transmission rate and second transmission rate. The first transmission rate correspond to a first path of the power line along which the signal is directly transmitted to the first power line communication apparatus, and the second transmission rate corresponds to a second path of the power line along which the signal is transmitted through the second power line communication apparatus to the first power line communication apparatus. A selector selects, based on the transmission rate information, a path corresponding to a higher transmission rate among the first and second paths. A transmitter transmits the signal through the selected path.

Power line communication apparatus, power line communication system, power line communication method and integrated circuit

The present invention provides a repeater which automatically closes a dynamically opened port in accordance with prior setting, the repeater including: a port mapping table where a global IP address and an external port number, or an external port number on the Internet is associated with a local IP address and an internal port number of a terminal connected to a LAN; a control unit which, receiving a communications packet to which an external port number is specified, converts the external port number to an internal port number based on the port mapping table and transfers the internal port number to the LAN; a timer unit which counts the unoccupied time of the port after transferring a communications packet to which an external port number is specified; and a port management unit which checks whether the registered machine is present on the LAN and in case it is absent, deletes registration concerning the external port number from the port mapping table.

Repeater and an inter-network repeating method

Growing community of inventors

Fukuoka, Japan

Akio Yao