A method of operation of a Multiprotocol Label Switching network involves, in an active node of the network, receiving a first data packet from a source node and forwarding the first data packet to a destination node. At the same time, the active node measures a residence time of the first data packet in the active node. The active node then sends a further data packet containing residence time information.

Upon receiving a dummy packet, a data collection terminal slave device (2) appends, to a return packet, a timestamp indicating the reception time of the dummy packet and a timestamp indicating the transmission time of the return packet, and transmits the return packet to a data collection terminal master device (3). When performing a time synchronization process, the data collection terminal master device (3) transmits the dummy packet to the data collection terminal slave device (2). Upon receiving the return packet, the data collection terminal master device (3) calculates a synchronization deviation time of the data collection terminal master device (3) and the data collection terminal slave device (2) and a propagation delay time between the data collection terminal master device (3) and the data collection terminal slave device (2), based on the transmission time of the dummy packet and the reception time of the return packet, and the reception time of the dummy packet and the transmission time of the return packet obtained from the timestamps of the return packet.

A time synchronization method includes receiving, by a receive-end device, a first timestamp and a first header signal sent by a transmit-end device, where the first timestamp indicates a first moment at which a first channel medium conversion module sends the first header signal, and a second moment at which the receive-end device receives the first header signal. The method further includes sending a second header signal to the transmit-end device, where a third moment at which the receive-end device sends the second header signal. The method further includes receiving a fourth timestamp sent by the transmit-end device, where the fourth timestamp indicates a fourth moment at which the transmit-end device receives the second header signal. The method further includes synchronizing time with the transmit-end device based on the first moment, the second moment, the third moment, and the fourth moment.

In one embodiment, a method receives a first time from a network device. The first time is derived from a first timing source in a first domain. The method receives a second time in a second domain from a second timing source. A difference time value is calculated between the first time and the second time. The method then sends the difference time value to the network device where the network device uses the difference time value to send a delay value to other computing devices to synchronize timing of the other computing devices in the second domain. The other computing devices are configured to synchronize the respective time using the delay value with mobile network devices to allow timing synchronization between the mobile network devices.

Methods and systems for providing a virtual HDBaseT link. In one embodiment, a first switch transmits packets over an Ethernet network that includes one or more hops. The payload of each of the packets includes an HDBaseT T-packet belonging to an HDBaseT session. A first processor sets, for each packet from among a plurality of the packets, a timestamp value in the packet to correspond to the time at which the packet is transmitted by the first switch. A second switch receives the packets over the Ethernet network. A second processor calculates a clock correction value based on the timestamps in the plurality of packets, and utilizes the clock correction value to perform at least one of the following: (i) control transmission, by the second switch, of data in T-packets in the payloads of the packets, and (ii) recover a source clock of native media delivered over the Ethernet network.

There is provided a method of clock management in a packet data network (PDN) implementing a time-transfer protocol and a clock controller configured to operate therein. The clock controller is configured to: obtain topology data informative of a master clock node and a slave clock node constituting end points of a PTP path in the PDN and further informative of at least part of transit nodes of said PTP path; periodically obtain data informative of queue size and link rate characterizing, during a collection period, the at least part of transit nodes in master-slave (MS) and slave-master (SM) directions; for each collection period, use the obtained queue-related data to estimate queue-induced delay asymmetry of the PTP path; and send the estimated value of queue-induced delay asymmetry to the slave node, the estimated value to be used by a clock residing on the slave node as delay asymmetry correction parameter.

A multi-device lip synchronization method and a device. A secondary device receives an RTCP packet sent by a primary device. The secondary device corrects an STC of the secondary device based on a PCR in the RTCP packet, a program clock frequency of the primary device, a program clock frequency of the secondary device, and an RTCP delay. Then the secondary device receives RTPs published by the primary device, splice the RTPs into a complete audio data frame, and store the audio data frame into a PCM buffer of the secondary device. The secondary device outputs the audio data frame in the PCM buffer.

A method of operation of a Multiprotocol Label Switching network involves, in an active node of the network, receiving a first data packet from a source node and forwarding the first data packet to a destination node. At the same time, the active node measures a residence time of the first data packet in the active node. The active node then sends a further data packet containing residence time information.

Methods and systems for enabling recovery of lost packets transmitted over a communication network. In one embodiment, a device includes a processor and a transmitter. The processor is configured to calculate a row parity packet (RPP) and a diagonal parity packet (DPP) for n packets. Each of the RPP, the DPP, and the n packets comprises n segments. The processor utilizes each packet, from among the n packets, to update parity values in the RPP and the DPP in such a way that each segment in the packet is used to update one segment in the RPP and at most one segment in DPP. The transmitter transmits the n packets, the RPP, and the DPP over the communication network. Receiving a subset of n members of a set comprising: the RPP, the DPP, and the n packets, enables recovery of two lost packets.

The present technology improves synchronization of a slave node with a master node in a network using PTP packets in which the slave node is coupled to the working master node through at least one boundary node. The technology establishes a synchronization communication session between the boundary node and the slave node in which the synchronization communication session is configured to measure a first timing delay from the boundary node to the slave node, and establishes a transparent communication session between the master node and the slave node through the boundary timing node in which the transparent communication session configured to measure a second timing delay from the master node to the slave node. Using the sessions, the technology adjusts a timing delay correction factor according to the first timing delay and the second timing delay, and synchronizes the slave node with the master node according to the correction factor.