CN-122027069-A - Accurate time protocol time synchronization method and equipment

Abstract

The application provides a method and equipment for synchronizing accurate time protocol time. The method comprises the steps of measuring downlink correction time delay and uplink correction time delay of a PON port and a PTP transparent transmission mode Ethernet interface UNI port, sending synchronous messages to switching equipment connected with the UNI port, recording synchronous message sending time, calculating synchronous message sending correction time based on addition of the synchronous message sending time and the downlink correction time delay, sending follow-up messages carrying the synchronous message correction sending time to the switching equipment, receiving delay request messages from the switching equipment, recording delay request message receiving time, subtracting the uplink correction time based on the delay request message receiving time, calculating delay request message receiving correction time, and sending delay response messages carrying the delay request message receiving correction time to the switching equipment so that the switching equipment calculates average path time delay.

Inventors

• PENG JIANYUAN

Assignees

• 新华三技术有限公司

Dates

Publication Date

20260512

Application Date

20260331

Claims (8)

1. 1. A method for accurate time protocol time synchronization, characterized in that the method comprises, Measuring the downlink correction time delay and the uplink correction time delay of the PON port and the PTP transparent transmission mode Ethernet interface UNI port; Sending a synchronous message to the switching equipment connected with the UNI port through the PON port; recording synchronous message sending time, and calculating synchronous message sending correction time based on addition of the synchronous message sending time and the downlink correction time delay; Sending a following message carrying the synchronous message correction sending time to the switching equipment through the PON port; Receiving a delay request message from the switching equipment through the PON port; Recording delay request message receiving time, and calculating delay request message receiving correction time based on the delay request message receiving time minus the uplink correction time delay; And sending a delay response message carrying the delay request message receiving correction time to the switching equipment through the PON port, so that the switching equipment calculates average path delay based on the synchronous message sending correction time, the following message receiving time, the delay request message sending time and the delay request message receiving correction time.
2. 2. The method of claim 1, wherein the measuring the downstream and upstream correction delays of the PON port and the PTP pass-through mode ethernet interface UNI port is preceded by, Transmitting a PTP transparent configuration command for the UNI port to the ONU through the PON port, wherein the PTP transparent configuration command comprises an encapsulation port bound with the UNI port and a fixed bandwidth transmission container; receiving a PTP transparent transmission capability response message from the ONU through the PON port; Transmitting a UNI port delay detection notification message to the ONU through the PON port, so that the ONU establishes a pair of ACL entries to loop the UNI port delay detection message back through the UNI port and back through the upstream PON port; and receiving a UNI port time delay detection ready message from the ONU through the PON port.
3. 3. The method of claim 2, wherein said measuring said downstream correction delay and said upstream correction delay comprises, Transmitting a UNI port delay detection message to the ONU through the PON port; recording the sending time of the detection message of the UNI port time delay detection message; Receiving the UNI port time delay detection message looped back by the ONU through the PON port; recording the detection message loopback receiving time of the time delay detection message of the UNI port which is received in a loopback way; and calculating the average value of the time difference between the sending time of the detection message and the receiving time of the detection message loop, and taking the average value as the downlink correction time delay and the uplink correction time delay.
4. 4. A method according to claim 3, characterized in that the method further comprises the steps of, Transmitting a PTP transparent transmission start notification message to the ONU through the PON port so that the ONU deletes the pair of ACL table items; And receiving a PTP transparent transmission start response message from the ONU through the PON port.
5. 5. An accurate time protocol time synchronization apparatus comprising a processor and a machine-readable storage medium, the processor executing machine-executable instructions recorded on the machine-readable storage medium to perform operations, Measuring the downlink correction time delay and the uplink correction time delay of the PON port and the PTP transparent transmission mode Ethernet interface UNI port; Sending a synchronous message to the switching equipment connected with the UNI port through the PON port; recording synchronous message sending time, and calculating synchronous message sending correction time based on addition of the synchronous message sending time and the downlink correction time delay; Sending a following message carrying the synchronous message correction sending time to the switching equipment through the PON port; Receiving a delay request message from the switching equipment through the PON port; Recording delay request message receiving time, and calculating delay request message receiving correction time based on the delay request message receiving time minus the uplink correction time delay; and sending a delay response message carrying the delay request message receiving correction time to the switching equipment through the PON port.
6. 6. The apparatus of claim 5, wherein the processor further performs the following operations prior to executing the machine executable instructions recorded on the machine readable storage medium to measure the downstream correction delay and the upstream correction delay of the PON port and the PTP pass-through mode ethernet interface UNI port, Sending a PTP transmission configuration command for the UNI port to the ONU through the PON port, wherein the PTP transmission configuration command comprises an encapsulation port and a fixed bandwidth transmission container which are bound by the UNI port; receiving a PTP transparent transmission capability response message from the ONU through the PON port; Transmitting a UNI port delay detection notification message to the ONU through the PON port; and receiving a UNI port time delay detection ready message from the ONU through the PON port.
7. 7. The apparatus of claim 6, wherein the processor executing the measuring the downstream correction delay and the upstream correction delay by executing machine-executable instructions recorded on the machine-readable storage medium comprises, Transmitting a UNI port delay detection message to the ONU through the PON port; recording the sending time of the detection message of the UNI port time delay detection message; Receiving the UNI port time delay detection message looped back by the ONU through the PON port; recording the detection message loopback receiving time of the time delay detection message of the UNI port which is received in a loopback way; and calculating the average value of the time difference between the sending time of the detection message and the receiving time of the detection message loop, and taking the average value as the downlink correction time delay and the uplink correction time delay.
8. 8. The apparatus of claim 7, wherein the processor further performs the following by executing machine-executable instructions recorded on the machine-readable storage medium, Transmitting a PTP transparent transmission start notification message to the ONU through the PON port so that the ONU deletes the pair of ACL table items; And receiving a PTP transparent transmission start response message from the ONU through the PON port.

Description

Accurate time protocol time synchronization method and equipment Technical Field The application relates to a communication technology, in particular to a method and equipment for synchronizing time of an accurate time protocol. Background In the existing access network, the time synchronization is widely applied to the scenes such as mobile forward/backward transmission, industrial control, power communication and the like, and the scenes have higher requirements on phase and clock consistency. The industry generally adopts an IEEE 1588v2 precise time protocol (Precision Time Protocol, PTP, precise time protocol) to distribute time in a packet Ethernet, and achieves microsecond or higher precision time setting capability by synchronizing message interaction and link delay measurement. Meanwhile, a passive Optical network (Passive Optical Network, PON, passive Optical network) is deployed in a large number as a typical access bearer, and the network structure is generally represented by setting an Optical line terminal (Optical LINE TERMINAL, OLT, optical line terminal) at a local side, where the OLT is connected to a plurality of Optical network units (Optical Network Unit, ONUs, optical network units) through an Optical distribution network, and the ONUs are accessed to devices such as a downstream switch, a base station, or an industrial terminal through a user-side ethernet interface (User Network Interface, UNI, user network interface). Under the above architecture, when the network needs to distribute the PTP time synchronization capability provided by the upstream switch to multiple downstream switches across the PON access network, the OLT needs to transmit the upstream PTP time received by its system side to each ONU through the PON system, and each ONU continues to output time to the locally accessed downstream switch on its UNI side in a PTP manner, thereby forming an end-to-end pair time link of "upstream switch-OLT-ONU-downstream switch". However, in actual networks, low-cost ONUs cannot provide PTP time-synchronized services to downstream switches. Disclosure of Invention The application aims to provide a method and equipment for synchronizing time of an accurate time protocol, which are used for realizing that an OLT provides PTP time synchronization service for downstream switching equipment of an ONU. The application provides a time synchronization method of an accurate time protocol, which comprises the steps of measuring downlink correction time delay and uplink correction time delay of a PON port and a PTP transparent mode Ethernet interface UNI port, sending synchronous messages to a switching device connected with the UNI port through the PON port, recording synchronous message sending time, calculating synchronous message sending correction time based on addition of the synchronous message sending time and the downlink correction time delay, sending follow-up messages carrying the synchronous message correction sending time to the switching device through the PON port, receiving delay request messages from the switching device through the PON port, recording the delay request message receiving time, subtracting the uplink correction time based on the delay request message receiving time, calculating delay request message receiving correction time, and sending delay response messages carrying the delay request message receiving correction time to the switching device through the PON port, so that the switching device calculates average path time delay based on the synchronous message sending correction time, the follow-up message receiving time, the delay request message sending time and the delay request message receiving correction time. In order to achieve the above object, the present application provides an accurate time protocol time synchronization device, which includes a processor and a machine-readable storage medium, wherein the processor executes machine-executable instructions recorded by the machine-readable storage medium, and the processor performs the following operations of measuring a downstream correction time delay and an upstream correction time delay of a PON port and a UNI port of an ethernet interface in a PTP transparent transmission mode, transmitting a synchronization message to a switching device connected to the UNI port through the PON port, recording a synchronization message transmission time, calculating a synchronization message transmission correction time based on an addition of the synchronization message transmission time and the downstream correction time delay, transmitting a following message carrying the synchronization message correction transmission time to the switching device through the PON port, receiving a delay request message from the switching device through the PON port, recording the delay request message reception time, subtracting the upstream correction time delay based on the delay request message reception time, calculating th