Apparatus for linking computers into networks; apparatus for network communication; apparatus for use in communications networks; communication devices for linking computer networks; communications networks; computer apparatus for use in local area networks; computer apparatus for use with computer networks; computer network apparatus; computer network installations; computer networking apparatus; computer networking installations; computer networks; computer networks for the communication of data; computer networks for the processing of data; computer programs for the creation of networks; computer programs relating to computer networks; computer programs relating to local area networks; connecting elements for communication networks; data networks; data transmission networks; devices for use in the networking of computers; local area networking apparatus for the switching of data; local area networking apparatus for the transmission of data; local area networks; network connector for radio networks; network controllers being computer apparatus; network controlling apparatus; packet switching networks; radio for radio communication networks; repeaters for use in data networking; telecommunications networks; antennas for wireless communication apparatus; wireless apparatus; wireless communication apparatus; wireless high frequency transmission instruments