A method is provided for initiating a configuration after the interruption of at least two ring-shaped networks arranged in parallel. After the appearance of malfunctions in the ring lines and ring switching matrix devices in at least two-of-n ring-shaped networks, a configuring in the sense of forming those ring network portions that are still intact into a new ring-shaped network is initiated. Based on the knowledge of the position of the subscriber equipment (interpretation of the address table information) and on the transmission of interrupt information given ring interruptions, the configuring or, respectively, "loop back" connecting is initiated after the identification of the reception and transmission of interrupt information or the identification of the transmission of interrupt information dependent on the position of the appertaining subscriber equipment.
A serial network fault isolation device for use in a network hub has receive and transmit buffers connected to the network. An isolation switch which allows the receive buffer to receive network signals while the transmit buffer sends signals such as media access control (MAC) frames supplied by the hub processor. A decoder connected to the receive buffer recognizes received (MAC) frames and interrupts the hub processor which reads the MAC frame. An idle character generator also under control of the hub processor is used to synchronize the circuit when the hub processor inserts the fault isolation device in the network.
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.
A data processing system comprises a number of processing nodes interconnected by a data transmission network. The network is "hairpin" shaped, having a first leg, a second leg, and a loopback connection connecting the first leg to the second leg. Each node sends public write messages on to the first leg, and receives messages from the second leg. All the messages flow through the loopback connection, which thus serves as a central chronology point for the system, defining a unique chronological order for the messages. The network can be reconfigured, to split it into a number of sub-networks, each with first and second legs interconnected by a loopback connection. The system may include a backup node, for disaster recovery, situated at a very long distance from the processing nodes.
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.
A token ring network performs address to port mapping by taking advantage of the abilities of the port switched modules and the neighbor notification process, in order to perform address to port mapping on each individual module. Ring monitors are switched from an upstream side of a port to a downstream side of a port when the neighbor notification process enters the port domain. The processor on the module records all the addresses received on the downstream side of the port, when the neighbor notification process is in the domain of that port. If it appears that the neighbor notification process is in the domain of two adjacent ports, the present invention only records addresses from the most downstream of the two adjacent ports, since such a situation is an indication that the upstream ports do not conform to MAC protocol. If a non-protocol station is connected to the last port in a module, the module will collect addresses from that port until the neighbor notification process enters the most upstream port of the module. At that point, addresses are no longer recorded in the most downstream port, and each set of addresses for each port are checked to determine if the last entry in each port has the ARI bits set to one and the source address is similar to the address of the most upstream neighbor of the module. If the addresses are the same, all addresses recorded in that port are ignored, since that port contains a non-protocol station.
