Abstract: A multistage relay communication system 100 includes a trunk network 1 and branch networks 2 (2a, 2b), each of which includes one or more communication apparatuses 4. The communication apparatus 4 can switch between a trunk mode to operate in the trunk network 1 and a branch mode to operate in the branch network 2. In the trunk network 1, the communication apparatus 4 carries out fixing of a communication path and redundancy of data based on a path table in order to achieve real-timeness and a data arrival rate. Meanwhile, in the branch network 2, when a communication failure occurs, the communication apparatus 4 autonomously searches for a communication path and constructs a path table, in order to at least secure a data arrival rate even if real-timeness is impaired within an allowable range.

Abstract: A communication device reduces a processing time required at the time of mutually converting different wireless or wired communication protocol and improves a real-time property. The communication device includes two or more communication units which communicate with two or more external devices and a communication controller which processes communication data. The communication controller has table information that associates a communication path, a type of the communication unit, and conversion-info, and an input and output unit that inputs and outputs the table information. According to the added conversion-info, a conversion unit sequentially performs various conversion processes (protocol conversion, routing, communication quality evaluation, fragmentation/integration of communication interface, fragment/defragment process, frame multiplication/integration, and frequency setting).

Abstract: A multistage relay communication system 100 includes a trunk network 1 and branch networks 2 (2a, 2b), each of which includes one or more communication apparatuses 4. The communication apparatus 4 can switch between a trunk mode to operate in the trunk network 1 and a branch mode to operate in the branch network 2. In the trunk network 1, the communication apparatus 4 carries out fixing of a communication path and redundancy of data based on a path table in order to achieve real-timeness and a data arrival rate. Meanwhile, in the branch network 2, when a communication failure occurs, the communication apparatus 4 autonomously searches for a communication path and constructs a path table, in order to at least secure a data arrival rate even if real-timeness is impaired within an allowable range.

Abstract: A communication device reduces a processing time required at the time of mutually converting different wireless or wired communication protocol and improves a real-time property. The communication device includes two or more communication units which communicate with two or more external devices and a communication controller which processes communication data. The communication controller has table information that associates a communication path, a type of the communication unit, and conversion-info, and an input and output unit that inputs and outputs the table information. According to the added conversion-info, a conversion unit sequentially performs various conversion processes (protocol conversion, routing, communication quality evaluation, fragmentation/integration of communication interface, fragment/defragment process, frame multiplication/integration, and frequency setting).