Abstract: End-to-end latency in a data network containing a succession of network devices through which a data packet passes via data connections is determined by first providing the data packet with a trigger packet. Then each device generates and adds to the trigger packet a respective reception timestamp indicating when the packet is received by the respective device. This added data indicates time needed for travel from the immediately upstream network device such that, when reaching the furthest downstream device of the succession of network devices, the trigger packet holds a plurality of timestamp representing when the trigger packet was received by the network devices. Finally the end-to-end latency is calculated at the furthest downstream network device from all of the time stamps in the trigger packet.

Abstract: The invention relates to a method for operating a network, wherein the network comprises a plurality of network devices having ports, the network devices being connected to one another for transmitting data via cables which are each inserted into a respective port, wherein each port has signaling means which can be switched between at least two signaling states. The invention is characterized in that all signaling means of those ports of the network devices, which have the same configuration, are brought into an associated detectable signaling state.

Abstract: A method for operating a data network, wherein the data network contains network devices that use data connections to interchange data packets, wherein a mechanism is operated in order to determine at least one end-to-end latency between network devices, characterized in that as a mechanism a network device transmits a trigger packet to at least one further network device and a timestamp is used to establish when the trigger packet has reached this at least one further network device.

Abstract: The invention relates to a method for operating a network, wherein network devices in the network exchange useful data among each other via at least one transfer medium by the transfer of useful data packets and at least one redundancy protocol is applied in order to reduce a failure risk, wherein said at least one redundancy protocol carries out a transfer of test data packets in order to detect failures in the network, wherein the invention combines known methods of dynamic redundancy protocols with test data packets and the use of frame preemption or time slot methods in three alternatives or methods which are combinable with each other, this considered individually or also in combination with each other thus enabling a significant reduction of the worst case detection time of a failure in the network, and consequently the reduction of the worst case changeover time in case of fault.

Abstract: The invention relates to a method for operating a network, wherein the network comprises a plurality of network devices having ports, the network devices being connected to one another for transmitting data via cables which are each inserted into a respective port, wherein each port has signaling means which can be switched between at least two signaling states. The invention is characterized in that all signaling means of those ports of the network devices, which have the same configuration, are brought into an associated detectable signaling state.

Abstract: A method of operating a network that has network infrastructure devices (1, 2) that have multiple ports and that are connected or are connectable to each other for data transmission via respective cables inserted into the ports that each have a signaling means that can be switched between at least two signaling states, characterized in that a signaling means of a port of the one network infrastructure device (1) and a signaling means of a port of another network infrastructure device (2) are brought into a signaling state indicating that they belong together so that it is easy to determine that the ports belong together.