The disclosure has an object to allow local expansion without causing any loop. The disclosure is a system to which two nodes respectively belonging to different ring networks are connected, wherein the two nodes are connected to each other using a predetermined customized port, upon receipt of a predetermined unicast frame, one of the two nodes transmits the frame to another of the two nodes using the customized port, upon receipt of the predetermined unicast frame from the customized port, the other of the two nodes forwards the unicast frame, and upon receipt of a frame different from the predetermined unicast frame from the customized port, the other of the two nodes discards the frame.

Rapid failure detection and recovery in wireless communication networks is needed in order to meet, among other things, carrier class Ethernet transport channel standards. Thus, resilient wireless packet communications is provided using a hardware-assisted rapid transport channel failure detection algorithm and a Gigabit Ethernet data access card with an engine configured accordingly. In networks with various topologies, this is provided in combination with their existing protocols, such as rapid spanning tree and link aggregation protocols, respectively.

Rapid failure detection and recovery in wireless communication networks is needed in order to meet, among other things, carrier class Ethernet transport channel standards. Thus, resilient wireless packet communications is provided using a hardware-assisted rapid transport channel failure detection algorithm and a Gigabit Ethernet data access card with an engine configured accordingly. In networks with various topologies, this is provided in combination with their existing protocols, such as rapid spanning tree and link aggregation protocols, respectively.

A high availability aircraft network architecture incorporating smart points of presence (SPoP) is disclosed. In embodiments, the network architecture divides the aircraft into districts, or physical subdivisions. Each district includes one or more mission systems (MS) smart network access point (SNAP) devices for connecting MS components and devices located within its district to the MS network. Similarly, each district includes one or more air vehicle systems (AVS) SNAP devices for connecting AVS components and devices within the district to the AVS network. The AVS network may remain in a star or hub-and-spoke topology, while the MS network may be configured in a ring or mesh topology. Selected MS and AVS SNAP devices may be connected to each other via guarded network bridges to securely interconnect the MS and AVS networks.

An apparatus and method for operating a ring interconnect are disclosed. The ring interconnect has a plurality of nodes that are used to connect to associated components, and is arranged to transport a plurality of slots around the ring interconnect between the nodes in order to transfer items of traffic allocated into those slots between components connected to the nodes. For each item of traffic, one of the components acts as a source to allocate that item of traffic into a slot, and another components acts as destination to seek to remove that item of traffic from the slot. In a default mode of operation, the ring interconnect is arranged to allow all of the slots to be available for transfer of any items of traffic. Special slot management circuitry is provided that is responsive to a throughput alert trigger indicating a potential for occurrence of a throughput inhibiting condition, to cause a slot amongst the plurality of slots to be reserved as a special slot that is constrained for use only when one or more determined conditions are met. Further, the one or more determined conditions are arranged to cause the special slot to be used in a manner that seeks to avoid the throughput inhibiting condition arising.

An apparatus and method for operating a ring interconnect are disclosed. The ring interconnect has a plurality of nodes that are used to connect to associated components, and is arranged to transport a plurality of slots around the ring interconnect between the nodes in order to transfer items of traffic allocated into those slots between components connected to the nodes. For each item of traffic, one of the components acts as a source to allocate that item of traffic into a slot, and another components acts as destination to seek to remove that item of traffic from the slot. In a default mode of operation, the ring interconnect is arranged to allow all of the slots to be available for transfer of any items of traffic. Special slot management circuitry is provided that is responsive to a throughput alert trigger indicating a potential for occurrence of a throughput inhibiting condition, to cause a slot amongst the plurality of slots to be reserved as a special slot that is constrained for use only when one or more determined conditions are met. Further, the one or more determined conditions are arranged to cause the special slot to be used in a manner that seeks to avoid the throughput inhibiting condition arising.

A first router in a first AS, the first router comprises: a processor configured to: obtain information about a broadcast link connecting the first router to a second router in a second AS, and generate a link state message comprising the information; and a transmitter coupled to the processor and configured to transmit the link state message to a third router, wherein the third router is in the first AS and is adjacent to the first router. A method comprises: receiving a first link state message from a first router; receiving a second link state message from a second router; receiving a third link state message from a third router; determining which of the first router, the second router, and the third router are ASBRs connected to a broadcast link based on information in the first link state message, the second link state message, and the third link state message.

A system of a machine includes a first node and a second node configured to establish a first communication path through a waveguide system to guide a radio frequency transmission between the first node and the second node in the machine. The system also includes a third node and a fourth node configured to establish a second communication path in the machine. The first node is grouped with the third node as a first node group, and the second node is grouped with the fourth node as a second node group such that the second communication path provides a redundant communication path with respect to the first communication path for communication between the first node group and the second node group.

A system of a machine includes a first node and a second node configured to establish a first communication path through a waveguide system to guide a radio frequency transmission between the first node and the second node in the machine. The system also includes a third node and a fourth node configured to establish a second communication path in the machine. The first node is grouped with the third node as a first node group, and the second node is grouped with the fourth node as a second node group such that the second communication path provides a redundant communication path with respect to the first communication path for communication between the first node group and the second node group.

A data bus subscriber connected to a local bus, particularly a ring bus. The data bus subscriber has a status signal input for receiving a first status signal value from a downstream data bus subscriber or a terminator, a status signal output for providing a second status signal value to an upstream data bus subscriber or to a local bus master, wherein the data bus subscriber is adapted to provide the second status signal value based on a logical link of a communication readiness of the data bus subscriber and the first status signal value. The invention further relates to a corresponding method and a local bus.