Abstract: A concentrator having a single medium access controller for monitoring a plurality of communication lines is provided. Each of the communication lines corresponds to a network and carries identification signals periodically transmitted by devices on the corresponding network. The medium access controller includes a transmit unit and a receive unit. The transmit unit sequentially broadcasts concentrator identification signals over each of the communication lines. The transmit unit sequences through the communication lines at a rate to insure that a concentrator identification signal is sent over each communication line during a predetermined transmit interval. The receive unit sequentially monitors the signals on each of the communication lines. The receive unit monitors the signals on any given communication line for a predetermined monitoring period before sequencing to the next communication line.

Abstract: A network process that automatically identifies and isolates a faulty station or group of stations within a token ring communication network in a timely manner. The present invention performs three different and separate processing strategies to identify and isolate faulty stations and or groups of stations within a token ring communication network. The processing of the present invention is accomplished simultaneously within the network management modules of each concentrator within the overall communication network. Upon receipt of beacon signals indicating a faulty station in the network, the present invention directs the NMM to isolate newly inserted stations or modules. If this is not successful then the present invention attempts a direct removal process if port address association data is present. If no port address association data is present then a brute force process is performed to identify and isolate the station or module that is generating a communication fault within the token ring network.

Abstract: A method and apparatus for associating stations to a port on a network concentrator. The network concentrator implements a network having a Ring based topology. Associating stations to ports provides for the coupling of multiple stations to a single port. Three maps are created which describe the network, a port map, a station map and an exit station map. The port map identifies the ports having one or more stations coupled to it. The station map identifies each station in the network. The exit station map identifies for each port with a station coupled to it, the station which transmits data into the port. By identifying the stations between two exit stations on adjacent ports in the network concentrator, the stations coupled to a port are determined. The identification of exit stations is facilitated by the use of an exit station detection circuit located at the port.

Abstract: A network process that automatically identifies and isolates a faulty station or group of stations within a token ring communication network in a timely manner. The present invention performs three different and separate processing strategies to identify and isolate faulty stations and or groups of stations within a token ring communication network. The processing of the present invention is accomplished simultaneously within the network management modules of each concentrator within the overall communication network. Upon receipt of beacon signals indicating a faulty station in the network, the present invention directs the NMM to isolate newly inserted stations or modules. If this is not successful then the present invention attempts a direct removal process if port address association data is present. If no port address association data is present then a brute force process is performed to identify and isolate the station or module that is generating a communication fault within the token ring network.

Abstract: Apparatus for monitoring and displaying the status of a local area network. The network includes a hub with ports for connection to various data terminal equipment in a star configuration and for connection to other hubs of the network. The hubs each have different types of plug-in modules which have ports for connecting the hub to different types of network cable such as fiber optic cable, unshielded twisted pair cable and shielded twisted pair cable. Information is automatically provided to a control console identifying the types of modules and the location of the modules in the hub so that an image of the actual hub can be displayed on the screen of the control console. The actual hub image shows the location and types of modules installed in the hub. In addition, information regarding the connection of each of the hubs to other hubs of the network is obtained and provided to the control console.