Abstract: A method of communicating data in a network comprises receiving a copy of a message on a first channel via at least one of a first port and a second port, the first port coupled to a first neighbor node and the second port coupled to a first neighbor's neighbor node; and selecting either the copy of the message received via the first port or the copy of the message received via the second port if a copy of the message is received via both the first port and the second port. If a copy of the message is only received via one of the first port or the second port, the received copy of the message is selected.

Abstract: The invention relates to a method for synchronizing local clocks in a distributed computer network, where said computer network consists of a number of components that are connected to each other via bi-directional communication links, characterized in that a) an a priori configured set of components of the network generates synchronization messages and sends these synchronization messages to the network, and b) an a priori configured set of components consumes the generated synchronization messages, and c) one or more message-relaying components in between a component that generates a synchronization message and the component that consumes the synchronization message will add a delay value to the synchronization message reflecting the delay imposed by the message-relaying component, d) a component that is configured to consume a synchronization message will delay a received synchronization message upon reception for a duration that is calculated by an a priory configured value for the maximum transmission de

Abstract: A network comprises a plurality of nodes; and a plurality of links communicatively coupling each of the plurality of nodes to at least one respective adjacent node of the plurality of nodes via a first communication channel and to another respective adjacent node of the plurality of nodes via a second communication channel. At least one of the plurality of nodes is a source node configured to source data. The source node is configured to form a virtual self-checking pair with one of the respective adjacent node on the first communication channel or the respective adjacent node on the second communication channel to achieve a consistent broadcast of data on the first and second communication channels. Data exchanged between the source node and the respective adjacent node in the virtual self-checking pair is only sourced by the source node.

Abstract: A method for synchronizing local clocks in a distributed computer network includes a number of components that are connected to each other via bi-directional communication links. An a priori configured set of components generates synchronization messages and sends these messages to the network. An a priori configured set of components consumes the generated messages. One or more message-relaying components in between a component that generates a synchronization message and the component that consumes the message adds delay value to the message reflecting the delay imposed by the message-relaying component. A component that is configured to consume a synchronization message delays a received synchronization message upon reception for a duration that is calculated by an a priori configured value for the maximum transmission delay minus the value of the sum of all delay values added to the received message before further usage of the message in the synchronization process.

Abstract: One embodiment comprises a network that includes a plurality of bi-directional links and a plurality of nodes. Each node is communicatively coupled to two neighbor nodes and to two skip nodes using the plurality of bi-directional links. Three neighboring nodes of the plurality of nodes form a triple modular redundant (TMR) set having a first end node, a second end node, and a center node, the first end node configured to transmit output data in a first direction and the second end node configured to transmit output data in a second direction.

Abstract: In an embodiment, an authentication system includes a supply device having a data storage chip with identification (ID) bit memory cells. The ID bit memory cells comprising a measured cell, pointer cells to store address information that points to the measured cell, and analog cells that store factory-measured analog information about the measured cell.

Abstract: A communication network comprises a communication medium and a plurality of nodes. Each node is configured to communicate with the other nodes using a protocol that has at least one of an idle period or a preamble period. The at least one node of the plurality of nodes is configured to transmit an out-of-band signal during at least one of the idle period or the preamble period and is configured to modify at least a portion of the out-of-band signal to communicate data to at least one other node. The at least one other node is configured to interpret the modified portion of the out-of-band signal to identify the data communicated in the modified out-of-band signal. The modified out-of-band signal complies with the protocol's encoding rules such that any node not configured to interpret the modified portion of the out-of-band signal processes the modified out-of-band signal according to the protocol.

Abstract: A system comprises a plurality of nodes, at least one of the plurality of nodes configured to insert, on a per-virtual link basis, a delay value into a dynamic delay field of a frame corresponding to the respective virtual link, wherein the dynamic delay value represents latency of frames of the respective virtual link. The system also comprises a switch having a plurality of ports, each port coupled to one of the plurality of nodes. The switch is configured to route frames received from the plurality of nodes to one or more of the plurality of nodes. At least one of the plurality of nodes is configured to store frames received from the switch in a buffer and to update the value in the dynamic delay field to reflect the end-to-end system delay.

Abstract: A system comprises a plurality of nodes; and a hub that is communicatively coupled to each of the plurality of nodes via a plurality of point-to-point links, wherein a priority-based arbitration scheme is used by the plurality of nodes and the hub to communicate over each of the plurality of point-to-point links. When the hub determines that one or more of the plurality of nodes is each transmitting a message having an identification field comprising a first sub-field and a second sub-field, the hub uses the first sub-field to select which node's message should be forwarded to the other nodes based, at least in part, on the priority-based arbitration scheme and forwards the selected node's message as it is received to the other nodes, continuing with the second sub-field of the selected node's message.

Abstract: A method comprises transmitting a plurality of copies of a message from each of a first transmission node and a second transmission node, each copy having a respective identification and forwarding each of the plurality of copies of the message among other nodes in the network based, at least in part, on the respective identification of each copy such that each copy of the message traverses a predetermined communication path among the other nodes. A respective first received copy is compared to a respective second received copy at each of the other nodes. The integrity of the respective first and second copies is validated at each of the other nodes if the copies match and the copies traversed disjoint communication paths.

Abstract: Methods and apparatus are provided for evaluating the performance of a Time Triggered Ethernet (TTE) system employing Time Triggered (TT) communication. A real TTE system under test (SUT) having real input elements communicating using TT messages with output elements via one or more first TTE switches during a first time interval schedule established for the SUT. A simulation system is also provided having input simulators that communicate using TT messages via one or more second TTE switches with the same output elements during a second time interval schedule established for the simulation system. The first and second time interval schedules are off-set slightly so that messages from the input simulators, when present, arrive at the output elements prior to messages from the analogous real inputs, thereby having priority over messages from the real inputs and causing the system to operate based on the simulated inputs when present.

Abstract: A communication network comprises a communication medium and a plurality of nodes. Each node is configured to communicate with the other nodes using a protocol that has at least one of an idle period or a preamble period. The at least one node of the plurality of nodes is configured to transmit an out-of-band signal during at least one of the idle period or the preamble period and is configured to modify at least a portion of the out-of-band signal to communicate data to at least one other node. The at least one other node is configured to interpret the modified portion of the out-of-band signal to identify the data communicated in the modified out-of-band signal. The modified out-of-band signal complies with the protocol's encoding rules such that any node not configured to interpret the modified portion of the out-of-band signal processes the modified out-of-band signal according to the protocol.

Abstract: A method of communicating data in a network comprises receiving a copy of a message on a first channel via at least one of a first port and a second port, the first port coupled to a first neighbor node and the second port coupled to a first neighbor's neighbor node; and selecting either the copy of the message received via the first port or the copy of the message received via the second port if a copy of the message is received via both the first port and the second port. If a copy of the message is only received via one of the first port or the second port, the received copy of the message is selected.

Abstract: A cluster comprises a plurality of end nodes that communicate with one another over at least one communication channel. Each end node is assigned a time slot for transmission of frames; wherein each node comprises a local guardian configured to prevent transmission of timing-related frames sourced from the respective end node. The cluster also comprises a special node that communicates with the plurality of end nodes, wherein the special node establishes a time base and sources timing-related frames to the plurality of end nodes. The transmission schedule includes at least one common scrubbing time slot during which each of the plurality of end nodes is configured to generate a timing-related frame. The special node is configured to determine if the local guardian in any of the plurality of nodes failed to prevent transmission of the respective generated timing-related frame during the common scrubbing time slot.

Abstract: A network comprises a plurality of nodes; and a plurality of links communicatively coupling each of the plurality of nodes to at least one respective adjacent node of the plurality of nodes via a first communication channel and to another respective adjacent node of the plurality of nodes via a second communication channel. At least one of the plurality of nodes is a source node configured to source data. The source node is configured to form a virtual self-checking pair with one of the respective adjacent node on the first communication channel or the respective adjacent node on the second communication channel to achieve a consistent broadcast of data on the first and second communication channels. Data exchanged between the source node and the respective adjacent node in the virtual self-checking pair is only sourced by the source node.

Abstract: A method for synchronizing local clocks in a distributed computer network, wherein end systems and switches of the network executes the method as a synchronization state machine, which uses three different frame types. The states in the state machine belong to an unsynchronized or to a synchronized set of states. All end systems being configured as Synchronization Master periodically send coldstart frames in one of the unsynchronized states, all end systems being configured as Synchronization Master react to the reception of a coldstart frame by sending a coldstart acknowledgment frame a first timeout after the reception of the coldstart frame on all replicated communication channels. First timeout is reset when a consecutive coldstart frame is received before the coldstart acknowledge is sent, and all Synchronization Masters react to the reception of a coldstart acknowledgment frame by starting a second timeout and enter a synchronized state when the second timeout expires.

Abstract: The goal of the present invention is to improve the useful data efficiency and reliability in the use of commercially available ETHERNET controllers, in a distributed real time computer system, by a number of node computers communicating via one or more communication channels by means of TT ETHERNET messages. To achieve this goal, a distinction is made between the node computer send time (KNSZPKT) and the network send time (NWSZPKT) of a message. The KNSZPKT must wait for the NWSZPKT, so that under all circumstances, the start of the message has arrived in the TT star coupler at the NWSZPKT, interpreted by the clock in the TT star coupler. The TT star coupler is modified, so that a message arriving from a node computer is delayed in an intelligent port of the TT star coupler until the NWSZPKT can send it precisely at the NWSZPKT into the TT network.

Abstract: The goal of the present invention is to improve the useful data efficiency and reliability in the use of commercially available ETHERNET controllers, in a distributed real time computer system, by a number of node computers communicating via one or more communication channels by means of TT ETHERNET messages. To achieve this goal, a distinction is made between the node computer send time (KNSZPKT) and the network send time (NWSZPKT) of a message. The KNSZPKT must wait for the NWSZPKT, so that under all circumstances, the start of the message has arrived in the TT star coupler at the NWSZPKT, interpreted by the clock in the TT star coupler. The TT star coupler is modified, so that a message arriving from a node computer is delayed in an intelligent port of the TT star coupler until the NWSZPKT can send it precisely at the NWSZPKT into the TT network.

Abstract: Methods and apparatus are provided for evaluating the performance of a Time Triggered Ethernet (TTE) system employing Time Triggered (TT) communication. A real TTE system under test (SUT) having real input elements communicating using TT messages with output elements via one or more first TTE switches during a first time interval schedule established for the SUT. A simulation system is also provided having input simulators that communicate using TT messages via one or more second TTE switches with the same output elements during a second time interval schedule established for the simulation system. The first and second time interval schedules are off-set slightly so that messages from the input simulators, when present, arrive at the output elements prior to messages from the analogous real inputs, thereby having priority over messages from the real inputs and causing the system to operate based on the simulated inputs when present.

Abstract: A system comprises a plurality of nodes, at least one of the plurality of nodes configured to insert, on a per-virtual link basis, a delay value into a dynamic delay field of a frame corresponding to the respective virtual link, wherein the dynamic delay value represents latency of frames of the respective virtual link. The system also comprises a switch having a plurality of ports, each port coupled to one of the plurality of nodes. The switch is configured to route frames received from the plurality of nodes to one or more of the plurality of nodes. At least one of the plurality of nodes is configured to store frames received from the switch in a buffer and to update the value in the dynamic delay field to reflect the end-to-end system delay.