A method for processing clock drift implemented by a first network element includes: receiving a first notification message transmitted by a second network element, the first notification message including a first clock difference between a first clock domain and a second clock domain acquired by the second network element, transmission of the first notification message being triggered by a clock drift between the first clock domain and the second clock domain being greater than a drift amplitude value, which is a maximum value of a change amplitude of a clock difference between the first and second clock domain; determining first time sensitive communication assistance information (TSCAI) according to the first clock difference; and transmitting the first TSCAI to a radio access network (RAN) device, the first TSCAI being used by the RAN device to perform time control on a data stream in the first clock domain.

A physical layer circuit includes registers and a timing circuit. The registers are configured to store a future time of day, a local hardware time and a compensation value. The timing circuit is configured to: determine a relationship between the local hardware time and a grandmaster time; select the future time of day; determine a difference between a local clock and a grandmaster clock and set the compensation value equal to the difference; subsequent to determining the difference, enable maintenance of a current time of day; when the local hardware time matches the future time of day, begin updating the current time of day based on the compensation value to match the grandmaster time; and adjust the compensation value to compensate for drift between the current time of day and the grandmaster time.

There is disclosed a method and system for controlling network timing precision of a seismic collector, and a terminal device. The method includes: using an interrupt mode to transmit a data packet; calculating an optimal network delay; and correcting a transmission error in a network timing process according to the optimal network delay, after which the physical layer of a server receives the data packet and sends the data from the physical layer of the server to the application layer of the server using the interrupt mode thereby timing the data packet.

A time synchronization mechanism is provided. A second transmission device includes: a transmission section configured to transmit packets for delay calculation for a plurality of wavelengths to the corresponding time transmission device simultaneously; and a reception section configured to calculate a propagation delay Dms on a path from the corresponding time transmission device to the second transmission device based on a difference between the arrival times of the packets for delay calculation for the plurality of wavelengths received, receive a propagation delay Dsm on a path from the second transmission device to the corresponding time transmission device calculated, and calculate a propagation delay Dmax that is larger than any of the propagation delay Dms and the propagation delay Dsm. The reception section transmits a received PTP packet to a slave node after a waiting delay Wms calculated by subtracting the propagation delay Dms from the propagation delay Dmax.

A method synchronizes frame counters for protecting data transmissions between a first end-device and a second end-device. The data, in particular data frames, are transferred between the first end-device and the second end-device. The data frames are provided with frame counters to protect the data transfer between the first end-device and the second end-device. The second end-device sends a first data frame to the first end-device. The first data frame contains a marker in its payload data. The first end-device sends back a second data frame as an answer to the second end-device. The second data frame contains a frame counter in the header data, and the second data frame contains the frame counter and the marker in its payload data.

A method and system of synchronizing a local clock with a master clock using a serial communication bus includes receiving by a serial data interface receiver a master time signal corresponding to a master clock, generating by a frequency tuning loop a time error signal corresponding to a difference between the master time signal and a local time signal, generating by the frequency tuning loop an actual frequency signal based on a base frequency and the time error signal, producing by the frequency tuning loop a command frequency error based on the actual frequency signal and the local time signal, and producing by the local clock an updated local time signal based on the command frequency error.

A method at a first device for synchronising a first clock of the first device to a second clock of a second device, includes receiving a first message comprising an identifier from a third device; generating a first timestamp in dependence on the time at which the first message is received at the first device according to the first clock; receiving a second message from the second device comprising the identifier and a second timestamp, the second timestamp having been generated in dependence on the time at which the second device received the first message from the third device according to the second clock; and adjusting the first clock in dependence on a time difference between a time indicated by the first timestamp and a time indicated by the second timestamp.

A reference time determining method and apparatus are provided, to prevent aberrations in a control instruction execution time caused by inconsistency between a reference time of a terminal and a reference time of a control device in the conventional technology. In this application, the terminal may receive a plurality of pieces of time reference information sent by the network device. When the terminal receives indication information from the network device, the terminal may select, based on the indication information, one piece of time reference information from the plurality of pieces of time reference information as first time reference information. The indication information indicates the first time reference information. After determining the first time reference information, the terminal may determine the reference time of the terminal based on the first time reference information.

The described implementations relate a Passive Optical Network (PON). In one implementation, the PON includes an Optical Network Unit (ONU) that has at least one transmitter subsystem component and an associated optical transmitter. The at least one transmitter subsystem component may be configured to be in an enabled state during a timeslot period assigned to the ONU for transmitting an upstream data burst and a disabled state after the timeslot ends.

A method synchronizes frame counters for protecting data transmissions between a first end-device and a second end-device. The data, in particular data frames, are transferred between the first end-device and the second end-device. The data frames are provided with frame counters to protect the data transfer between the first end-device and the second end-device. The second end-device sends a first data frame to the first end-device. The first data frame contains a marker in its payload data. The first end-device sends back a second data frame as an answer to the second end-device. The second data frame contains a frame counter in the header data, and the second data frame contains the frame counter and the marker in its payload data.