This disclosure describes methods to process timing information of flows in a network. One or more processors determine a latency associated with each of one or more packets of a flow passing through a device. The one or more processors determine that the latency is greater than a baseline latency, and the one or more processors provide a message indicating at least the flow and that the latency is greater than the baseline latency.

A method performed by a transmitting device, in a 3GPP wireless communication 5 system (100), for handling generalized Precise Timing Protocol (gPTP) signaling, from a Time Sensitive Network (TSN) is provided. The transmitting device receives (1301) a gPTP frame from the TSN network. The gPTP frame comprises time information, an indication of a time domain related to the time information and/or a Medium Access Control (MAC) address of a second end station connected to a receiving device. Based 10 on the indication of the time domain and/or the MAC address, the transmitting device determines (1302) the receiving device which the gPTP frame relates to. The transmitting device transmits (1304), to the determined receiving device, the gPTP frame in a PDU session related to the determined receiving device.

[Problem] To provide a time synchronization mechanism that is not affected by link asymmetry between time synchronization devices.

[Solution] A DC 4 used in a time transmission system that transmits and receives a PTP packet between a master node 1 and a slave node 2 via the DC 4 and synchronizes time of the slave node 2 based on time information on the transmission and reception includes a PTP clock unit 12 that synchronizes time information by the arrived PTP packet, a frequency clock unit 21 that synchronizes time information by a frequency signal, a delay setting unit 22 that sets, such that a transmission delay of the PTP packet between the master node 1 and the slave node 2 becomes a setting delay Lmax, a waiting time of the PTP packet based on a time difference between a departure time of the PTP packet and an arrival time of the PTP packet at the DC 4, which is determined from the time information of the frequency clock unit 21, and a time adjustment unit 26 that corrects a time shift from reference time in the time information of the frequency clock unit 21 based on the time information of the PTP clock unit 12.

This application provides a communication processing method and apparatus. The method includes: receiving, by a target node, a second message sent by a synchronization source node via at least one intermediate node, where the second message carries a receiving time of a first message from the target node at the synchronization source node and waiting time information of the first message at each of the at least one intermediate node; and determining, by the target node, a clock deviation between the target node and the synchronization source node based on a sending time of the first message at the target node and the second message.

The Digital Time Processing over Time Sensitive Networks (DTP TSN) disclosed herein is contributing methods, systems and circuits for using a Precision Time Protocol (PTP) such as IEEE 1588 for distributing a master time secured by a master unit to slave units by utilizing slave clocks recovered from PTP messages and/or compatible with them data receiver clocks for maintaining a local slave time which is increased to a local master time by adding to it an estimate of a transmission delay derived by processing PTP messages, wherein such distribution of the master time includes filtering out phase noise of a timing referencing signals communicated by PTP messages in order to produce accurate timing implementing signals such as the slave clock, local slave time and local master time.

Synchronization of clocks among computing devices in a network includes determining master/slave relations among the computing devices. Some computing devices (e.g., switches) include trunk ports configured to carry traffic for several logical networks; e.g., virtual local area networks, VLANs. A trunk port can be associated with a master/slave setting for each logical network that it is configured for. Synchronization of clocks among the computing devices further includes running a synchronization sequence between a trunk port and each computing device on each of the logical networks configured on the trunk port.

Time stamp replication within wireless networks is described. In an embodiment, a wireless station receives an input time stamp and uses this input time stamp to generate an output time stamp. The wireless station transmits the output time stamp to wireless stations in one of a number of groups which make up the wireless network. The output time stamp is generated to compensate for delays between receiving the input time stamp and transmitting the output time stamp such that output time stamp which is transmitted at a time T corresponds to the value that the input time stamp would have had if it had been received at time T (and not at a time earlier than T). This may, therefore, reduce or eliminate independent time stamp errors and jitter caused by multiple disparate systems and processes.

Methods, systems, and devices for wireless communications are described. In an example, a method includes a first node receiving a precision time protocol (PTP) message, identifying one or more timing domains to be supported by the first node based at least in part on the PTP message, and sending, to a second node of the wireless communication network, an indicator of the one or more timing domains to be supported by the first node. Another example at a node includes receiving, from additional nodes of the wireless communication network, indicators of one or more timing domains supported by the additional nodes, receiving a PTP message associated with a timing domain, and sending the PTP message to a subset of the additional nodes based at least in a part on the indicators of one or more timing domains supported by the additional nodes.

Embodiments relate to optical transport technologies, and more specifically, to a clock transmission method. Under this method, a first optical data unit (ODU) container can be obtained. Phase discrimination can be performed on an obtained first clock and a first ODU clock of a transmit end, to generate a first PD value. The first PD value can then be inserted into an overhead of the first ODU container. The first ODU container can be encapsulated into a second ODU container, and the second ODU container can be sent. A rate of the second ODU container is higher than a rate of the first ODU container. The first PD value is transmitted in the first ODU container which is not decapsulated in a subsequent transmission process. Therefore, final recovery of the first clock is not affected, so that a deviation between a finally recovered clock and the first clock is greatly reduced.

A distributed Precision Time Protocol (PTP) Transparent Clock (TC) provides a TC function based on overall residence time in a network at a server layer. That is, the server layer operates as a distributed TC for a corresponding client layer. A transport network includes a first node connected to a first client device; and a second node connected to a second client device over a server layer, wherein the first client device communicates to the second client device via a client layer, wherein the first node and the second node are synchronized to one another, and wherein the first node and the second node are configured to implement a distributed transparent clock on a PTP packet at the client layer, the distributed transparent clock includes a correction field in the PTP packet based on a residence time in the transport network at the server layer.