A wireless local area network includes a plurality of stations each comprising a data processing machine connected to a radio send-receive interface. Each data processing machine includes an interface controller for sending a message containing an address designating a destination station...http://www.google.de/patents/US5818822?utm_source=gb-gplus-sharePatent US5818822 - Wireless local area network having interface at each station which ignores messages not retransmitted by repeater 
