A method of transmitting packets between a plurality of nodes of a network. The method comprising in each of a plurality of data timeslots, transmitting a data packet with one of the plurality of nodes and listening to receive the data packet with the remainder of the plurality of nodes. The method further comprising in each of one or more parity timeslots following the plurality of data timeslots, transmitting a parity packet with one or more of the plurality of nodes and listening to receive the parity packet with the remainder of the plurality of nodes. Each parity packet is derived from a set of the data packets transmitted during the plurality of data timeslots.

An audio system, method, and computer program product for synchronizing device clocks. The systems, methods and computer program product can establish a first isochronous data stream between a peripheral device and a first device and establish a second isochronous data stream between the first device and a second device to send data between the first and second device. As the two data streams may rely on two different device clocks, e.g., one clock which defines the timing for the first isochronous data stream and a second clock which defines the timing for the second isochronous data stream, the systems, methods, and computer program disclosed herein are configured to maintain synchronization and/or synchronize the first clock with the second clock to prevent data loss due to clock drift.

A time synchronization system includes a master and slave devices connected to each other via a data bus and a signal line dedicated to transmission of a fixed-period signal. The master device transmits the fixed-period signal through the signal line regularly at a transmission period, and transmits start time information indicating a transmission start time at which transmission of the fixed-period signal is started and transmission period information indicating the transmission period for the fixed-period signal through the data bus. The slave device counts a number of times the fixed-period signal is received and calculates, as a current time in the master device, a transmission time at which the master device transmits the fixed-period signal based on the number of times the fixed-period signal is received. The slave device corrects the time to the calculated current time in the master device.

A communication device according to an embodiment includes one or more hardware processors. The one or more hardware processors: receives, from a server device performing communication by a communication method of synchronizing a number indicating a communication timing, a reference number indicating the number serving as a reference; and determines a processing timing of predetermined processing, based on the reference number.

A real-time Ethernet (RTE) protocol includes start-up frames originated by a master device for network initialization including a preamble, destination address (DA), source address (SA), a type field, and a status field including state information that indicates a current protocol state that the Ethernet network is in for the slave devices to translate for dynamically switching to one of a plurality of provided frame forwarding modes. The start-up frames include device Discovery frames at power up, Parameterization frames that distribute network parameters, and Time Synchronization frames including the master's time and unique assigned communication time slots for each slave device. After the initialization at least one data exchange frame is transmitted exclusive of SA and DA including a preamble that comprises a header that differentiates between master and slave, a type field, a status field excluding the current protocol state, and a data payload.

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.

A network subscriber of an automation communication network is provided to exchange data with further network subscribers in the automation communication network at a predetermined clock frequency. The network subscriber has an internal clock for synchronizing the data exchange with at least one other network subscriber. The internal clock is embodied to provide a time as an integer count value. The clock frequency is determined in such a way that a period duration per clock pulse cannot be represented as an integer count value by the internal clock. A method of operating the network subscriber in the automation communication network comprises the following method step: the internal clock is incremented with a predetermined sequence of integer increments. The sequence of integer increments is predetermined such that a sum of the integer increments corresponds to an integer multiple of the period duration.

Techniques are described to provide for re-timing a packetized radio flow to clean noise induced by packet delay variation of a packet network. In one example, a method includes receiving, at a first node of a fronthaul network, a Radio over Ethernet (RoE) frame transmitted by a second node in which the RoE frame comprises a Common Public Radio Interface (CPRI) bit stream associated with a first radio device, a sequence number, and a first time stamp. The method may further include generating a second time stamp by the first node upon obtaining the RoE frame; calculating an induced delay value based, at least in part, on the first time stamp and the second time stamp; calculating a re-timing value based on a re-timing interval and the induced delay value; and transmitting the CPRI bit stream to a second radio device based on the re-timing value.

A method for exchanging a clock synchronization packet performed by a network apparatus, including: exchanging a clock synchronization packet with a first clock source, where the network apparatus includes a boundary clock; determining a first time deviation of the boundary clock relative to the first clock source according to the clock synchronization packet exchanged with the first clock source, where the boundary clock avoids performing an operation of calibrating a time of a local clock of the boundary clock according to the first time deviation; and sending a clock synchronization packet to a first slave clock of the boundary clock, where the clock synchronization packet includes a first timestamp, a value of the first timestamp is equal to a first corrected value, and the first corrected value is a value obtained by the boundary clock by correcting the time of the local clock by using the first time deviation.

Systems and methods are disclosed herein for performing a time-triggered distribution of messages from a region of networked machines to multiple destinations. In an embodiment, the system runs a software-based synchronization process to synchronize each of a plurality of gateways with a reference clock, wherein each gateway is a machine on a perimeter of the region of networked machines and is connected to transmit messages to multiple destinations. The gateways receive messages from within the region of networked machines for distribution to multiple destinations outside the region of networked machines according to a distribution schedule based on absolute time relative to the reference clock. The gateways perform the distribution of received messages, wherein each gateway determines absolute time based on that gateway's synchronization with the reference clock.