CN108270500A - A kind of method for synchronizing time and device - Google Patents

Abstract

The present invention provides a kind of method for synchronizing time and device, this method include：Each slave device network node is established to the transmission path of master network node so that the corresponding a length of mutually different optical wavelength of light wave of each transmission path；The synchronizing information of each slave device network node is controlled to load on the optical wavelength signal of corresponding optical wavelength, and be transmitted on the transmit path；Wherein, when the network node that transmission path is passed through includes master network node, slave device network node and an at least middleware network node, during optical wavelength signal transmits, middleware network node forwards the optical wavelength signal received in photosphere.Since the middleware network node of transmission path is when receiving the optical wavelength signal for carrying synchronizing information, it need not carry out photoelectric conversion processing, the optical wavelength signal directly is forwarded in photosphere, so as to which middleware network node is avoided to carry out the time error that photoelectric conversion processing introduces to optical wavelength signal.

Description

A time synchronization method and device

technical field

The invention relates to the technical field of the Internet, in particular to a time synchronization method and device.

Background technique

TD-SCDMA, CDMA2000, TD-LTE and other mobile communication systems have time synchronization requirements, and the base stations need to meet microsecond-level time synchronization, otherwise, it will cause base station interference and call connections cannot be established. In order to solve the problem of time synchronization, the high-precision time synchronization network sets up a time server upstream, and transmits time information step by step through intermediate nodes, and distributes time information to end base stations. The time transfer protocol usually adopts the IEEE PTP (Precise Time Synchronization) protocol.

In the prior art, when the synchronization network is processed by intermediate nodes at each level, the intermediate nodes extract the time synchronization message, process and calculate the time deviation, which is used to adjust the time of the node, and generate a new time synchronization message to be sent downstream. Time errors will be introduced during the processing of each node, so the time errors accumulate after multi-hop network transmission. According to the existing ITU-T G.8273.2 standard, the time error introduced by each hop intermediate node is on the order of tens of nanoseconds, so it is difficult to meet the accuracy requirements of hundreds of nanoseconds after network transmission. Therefore, there is a technical problem of poor time synchronization accuracy in the existing time synchronization method.

Contents of the invention

Embodiments of the present invention provide a time synchronization method and device to solve the technical problem of poor time synchronization accuracy.

In the first aspect, the embodiment of the present invention provides a time synchronization method applied in a synchronous transmission network, including:

Establishing transmission paths from each slave device network node to the master device network node, so that the optical wavelengths corresponding to each of the transmission paths are different optical wavelengths;

Controlling the synchronization information of each slave device network node to be loaded on the optical wavelength signal corresponding to the optical wavelength, and transmitted on the transmission path, so that the slave device network node can perform time synchronization adjustment according to the synchronization information;

Wherein, when the network nodes passed by the transmission path include the master device network node, the slave device network node and at least one intermediate device network node, during the transmission of the optical wavelength signal, the intermediate device network node Forwarding the received optical wavelength signal at the optical layer.

In the second aspect, the embodiment of the present invention also provides a time synchronization method, which is applied to the second device network node of the synchronous transmission network, including:

Receiving an optical wavelength signal carrying synchronization information sent by the master network node, the optical wavelength signal is a signal transmitted by a transmission path from the master network node to the second device network node, and the transmission path has an independent optical wavelength;

When the second device network node is an end node of the transmission path, perform time synchronization adjustment according to the synchronization information;

When the second device network node is an intermediate device network node of the transmission path, the forwarding of the optical wavelength signal at the optical layer is controlled according to the transmission path.

In the third aspect, the embodiment of the present invention also provides a time synchronization device, which is applied in a synchronous transmission network, including:

A path establishment module, configured to establish transmission paths from each slave device network node to the master device network node, so that the optical wavelengths corresponding to each of the transmission paths are different optical wavelengths;

The control module is used to control the synchronization information of each slave device network node to be loaded on the optical wavelength signal corresponding to the optical wavelength, and to transmit on the transmission path, so that the slave device network node can perform the synchronization according to the synchronization information. Time synchronization adjustment;

Wherein, when the network nodes passed by the transmission path include the master device network node, the slave device network node and at least one intermediate device network node, during the transmission of the optical wavelength signal, the intermediate device network node Forwarding the received optical wavelength signal at the optical layer.

In the fourth aspect, the embodiment of the present invention also provides a time synchronization device, which is applied in the second equipment network node of the synchronization transmission network, including:

The receiving module is configured to receive an optical wavelength signal carrying synchronization information sent by the main equipment network node, the optical wavelength signal is a signal transmitted by a transmission path from the main equipment network node to the second equipment network node, and the transmission path has Independent light wavelength;

An adjustment module, configured to perform time synchronization adjustment according to the synchronization information when the second device network node is an end node of the transmission path;

A forwarding module, configured to control the forwarding of the optical wavelength signal at the optical layer according to the transmission path when the second device network node is an intermediate device network node of the transmission path.

In this way, in the embodiment of the present invention, the transmission paths from each slave device network node to the master device network node are established, so that the optical wavelengths corresponding to each of the transmission paths are different optical wavelengths; The synchronization information is loaded on the optical wavelength signal corresponding to the optical wavelength, and transmitted on the transmission path, so that the slave device network node can perform time synchronization adjustment according to the synchronization information; wherein, when the transmission path passes When the network node includes the master device network node, the slave device network node, and at least one intermediate device network node, during the transmission of the optical wavelength signal, the intermediate device network node layer forwarding. Since an independent optical wavelength is set for the synchronization information during the transmission of the synchronization information, the optical wavelength signal carrying the synchronization information can be directly extracted from the device network node, and the synchronization information can be obtained, thereby shortening the time for obtaining the synchronization information and reducing the Difficulty in obtaining synchronization information and reducing time calculation errors. At the same time, when the intermediate device network node of the transmission path receives the optical wavelength signal carrying synchronization information, it does not need to perform photoelectric conversion processing, and directly forwards the optical wavelength signal at the optical layer, thereby avoiding the intermediate device network node from adjusting the optical wavelength signal. The time error introduced by the photoelectric conversion processing of the signal. Therefore, the present invention improves the accuracy of time synchronization, and since errors are only introduced in the master network node and the slave device network node of the transmission path, it can meet the precision requirement of hundreds of nanoseconds.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments of the present invention. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained based on these drawings without any creative effort.

Fig. 1 is a flow chart of the time synchronization method provided by the first embodiment of the present invention;

Fig. 2 is a schematic diagram of the network architecture of the application of the time synchronization method provided by the present invention;

Fig. 3 is one of the signal transmission schematic diagrams of the intermediate device network node of the time synchronization method provided by the present invention;

Fig. 4 is the second schematic diagram of signal transmission of the intermediate device network node of the time synchronization method provided by the present invention;

Fig. 5 is one of schematic diagrams of the time synchronization mode of the time synchronization method provided by the present invention;

Fig. 6 is the second schematic diagram of the time synchronization mode of the time synchronization method provided by the present invention;

FIG. 7 is a flow chart of the time synchronization method provided by the second embodiment of the present invention;

FIG. 8 is a structural diagram of a time synchronization device provided by a third embodiment of the present invention;

FIG. 9 is a structural diagram of a time synchronization device provided by a fourth embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

first embodiment

Referring to FIG. 1, FIG. 1 is a flowchart of a time synchronization method provided by an embodiment of the present invention. The time synchronization method is applied in a synchronous transmission network, as shown in FIG. 1, and includes the following steps:

Step 101, establishing transmission paths from each slave device network node to the master device network node, so that the optical wavelengths corresponding to each of the transmission paths are different optical wavelengths;

The time synchronization method provided in this embodiment is mainly applied in a synchronous transmission network, and is used to perform time synchronization for each network node in the synchronous transmission network.

Specifically, the above-mentioned master device network node may be a node in the middle of the synchronous transmission network, or may be a time reference source device; the above-mentioned slave device network node may be any node in the synchronous transmission network. Since time synchronization usually requires each slave network node to perform time synchronization with the master network node, so in this embodiment, a transmission path from each slave network node to the master network node needs to be established.

It should be noted that the synchronous transmission network includes a master device network node and a second device network node, and the second device network node includes a slave device network node and an intermediate device network node, wherein the slave device network node is used for The node that performs time synchronization with the synchronization information in the transmission path, that is, the end node on the transmission path; the intermediate device network node is a node for forwarding the optical wavelength signal, that is, the intermediate node on the above transmission path. In one transmission path, it may include only the master network node and the slave device network node, or may include the master device network node, the slave device network node and at least one intermediate device network node.

As shown in FIG. 2 , the synchronous transmission network includes a master network node N1 , a second network node N2 , a second network node N3 , a second network node N4 and a second network node N5 . For this purpose, four transmission paths can be established in the synchronous transmission network, namely: N2 to N1, N3 to N1, N4 to N1, and N5 to N1.

In this step, after the above transmission paths are established, each transmission path corresponds to an independent optical wavelength. For example, the optical wavelength of the path N2 to N1 is λ1, the optical wavelength of the path N3 to N1 is λ2, the optical wavelength of the path N5 to N1 is λ4, and the optical wavelength of the path N4 to N1 is λ4. Among them, the values of λ1, λ2, λ3 and λ4 are not equal.

Step 102, control the synchronization information of each slave device network node to be loaded on the optical wavelength signal corresponding to the optical wavelength, and transmit on the transmission path, so that the slave device network node can perform time synchronization according to the synchronization information Adjustment;

Wherein, when the network nodes passed by the transmission path include the master device network node, the slave device network node and at least one intermediate device network node, during the transmission of the optical wavelength signal, the intermediate device network node The received optical wavelength signal is forwarded at the optical layer.

The above synchronization information includes the synchronization information sent by the master network node to the slave network node, and the synchronization message sent by the slave network node to the master network node.

In this embodiment, control signaling can be sent or the transmission mode of synchronization information between the master device and each slave device can be configured through a configuration file, so that the synchronization information of each slave device network node is loaded on the optical wavelength signal corresponding to the optical wavelength, and transmission over the transmission path.

For example, the paths N2 to N1 include only the master network node N1 and the slave network node N2, and the paths N3 to N1 include the master network node N1, the intermediate device network node N2 and the slave network node N3.

When the main device network node sends synchronization information to each second device network node, the synchronization information of the second device network node N2 can be loaded in an optical wavelength signal with an optical wavelength of λ1 for transmission, and the synchronization information of the second device network node N3 It can be loaded in an optical wavelength signal with an optical wavelength of λ2 for transmission. At this time, when the second device network node N2 receives the optical wavelength signal with an optical wavelength of λ1, it will convert the optical wavelength signal into an electrical signal for processing, thereby obtaining the synchronization information carried by the optical wavelength signal, and performing time synchronization according to the synchronization information Processing; when the second equipment network node N2 receives an optical wavelength signal with an optical wavelength of λ2, it will directly forward the optical wavelength signal to the second equipment network node N3 at the optical layer, and the second equipment network node N3 receives the optical wavelength signal When it is an optical wavelength signal of λ2, the optical wavelength signal is converted into an electrical signal for processing, so as to obtain the synchronization information carried by the optical wavelength signal, and perform time synchronization processing according to the synchronization information.

In this way, in the embodiment of the present invention, the transmission paths from each slave device network node to the master device network node are established, so that the optical wavelengths corresponding to each of the transmission paths are different optical wavelengths; The synchronization information is loaded on the optical wavelength signal corresponding to the optical wavelength, and transmitted on the transmission path, so that the slave device network node can perform time synchronization adjustment according to the synchronization information; wherein, when the transmission path passes When the network node includes the master device network node, the slave device network node, and at least one intermediate device network node, during the transmission of the optical wavelength signal, the intermediate device network node is responsible for the received optical wavelength signal forwarded at the optical layer. Since an independent optical wavelength is set for the synchronization information during the transmission of the synchronization information, the optical wavelength signal carrying the synchronization information can be directly extracted from the device network node, and the synchronization information can be obtained, thereby shortening the time for obtaining the synchronization information and reducing the Difficulty in obtaining synchronization information and reducing time calculation errors. At the same time, when the intermediate device network node of the transmission path receives the optical wavelength signal carrying synchronization information, it does not need to perform photoelectric conversion processing, and directly forwards the optical wavelength signal at the optical layer, thereby avoiding the intermediate device network node from adjusting the optical wavelength signal. The time error introduced by the photoelectric conversion processing of the signal. Therefore, the present invention improves the accuracy of time synchronization, and since errors are only introduced in the master network node and the slave device network node of the transmission path, it can meet the precision requirement of hundreds of nanoseconds.

Further, the control mode for controlling the intermediate equipment network nodes to forward the optical wavelength signal can be set according to actual needs, and two different implementation schemes will be described in detail below.

For example, referring to FIG. 3, forwarding the received optical wavelength signal at the optical layer by the above-mentioned intermediate device network node includes:

Based on the optical combiner and demultiplexer in the intermediate device network node, the optical wavelength signal is directly passed through the intermediate device network node.

As shown in Figure 3, in this embodiment, an optical multiplexer and demultiplexer and an electrical processing unit are arranged in the network node of the intermediate device, and one of the optical multiplexer and demultiplexer is used to receive the optical wavelength signal sent by the upstream network node or send it to the upstream network node For the optical wavelength signal, another optical multiplexer and demultiplexer is used to receive the optical wavelength signal sent by the downstream network node or send the optical wavelength signal to the downstream network node.

In this embodiment, the optical combiner and demultiplexer can be set, and when an optical wavelength signal of a specific optical wavelength is received, the optical wavelength signal can be directly passed through the intermediate device network node. That is, when an optical wavelength signal sent by an upstream network node is received, the optical wavelength signal can be directly sent to another optical multiplexer/demultiplexer, and another optical multiplexer/demultiplexer directly forwards it to a downstream network node. In addition, the forwarding process of the optical wavelength signal sent by the downstream network node to the upstream network node is the same, and will not be repeated here.

Referring to FIG. 4, forwarding of the received optical wavelength signal at the optical layer by the above-mentioned intermediate device network node includes:

Dynamic wavelength scheduling is performed based on an OADM Optical Add-Drop Multiplexer (OADM Optical Add-Drop Multiplexer) device in the intermediate device network node, so that optical wavelength signals are passed through in the intermediate device network node.

As shown in Figure 4, a ROADM (Reconfigurable Optical Add-Drop Multiplexer) is installed in the network node of the intermediate equipment, and the configuration is performed by configuring the ROADM, and the ROADM is controlled to perform dynamic wavelength scheduling, so that the optical Wavelength signals pass through within the intermediate device network node. It should be understood that the processing of the optical wavelength signal in this embodiment refers to the processing of the optical wavelength signal carrying the synchronization information, and other optical wavelength processing methods can be processed according to existing methods.

It should be noted that, in this embodiment, the optical wavelength signals transmitted in the above transmission path may also include optical wavelength signals of other services in addition to the optical wavelength signals carrying synchronization information. That is, in this embodiment, the wavelength used for synchronous transmission can carry other services simultaneously on the wavelength without affecting the synchronous service. For example, synchronization information is carried by PTP Ethernet packets, and Ethernet packets of other services can be carried on this wavelength at the same time.

Further, in order to reduce the error introduced by the asymmetry of uplink and downlink delays, the transmission mode of the channel used to transmit the optical wavelength signal includes a single-fiber bidirectional mode.

That is, in this embodiment, a forward transmission optical wavelength and a reverse transmission optical wavelength are separately assigned to the above-mentioned transmission path, wherein the forward transmission optical wavelength is used for forward synchronization information transmission, and the reverse transmission optical wavelength is used for reverse transmission. The synchronization information is transmitted, and the forward synchronization information and the reverse synchronization information are transmitted in the same optical fiber, so that the error caused by the asymmetry of the uplink and downlink delays during synchronization can be avoided. It can be understood that, except for the wavelength where the synchronization information is located, the wavelengths where other services are located can still be transmitted in the dual-fiber bidirectional mode.

Further, the manner of synchronous transmission in the synchronous transmission network can be set according to actual needs. For example, in the first solution, the time synchronization between the slave device network node and the master device network node can be performed by means of two-way synchronization messages. In the second solution, the link delay information can also be recorded, and the master device network node Time synchronization is performed by means of transmitting time information, which will be described in detail below.

In the first scheme, the above-mentioned synchronization information includes a two-way synchronization message, and the two-way synchronization message is used for the slave device network node to calculate the time offset value with the master device network node according to the two-way synchronization message, and perform Time synchronization adjustment.

As shown in Figure 5, two-way synchronization message interaction can be periodically performed between the master device network node and the slave device network node, so that the slave device network node calculates the time with the master device network node according to the two-way synchronization message Deviation value, and periodically adjust the time synchronization, so as to achieve time synchronization between the slave device network node and the master device network node.

In the second solution, the synchronization information includes synchronization time information sent by the master network node to the slave network node, and the synchronization time information is used for the slave network node to follow the synchronization time information and the transmission path time synchronization adjustment based on the link delay information.

As shown in FIG. 6 , since the intermediate device network node does not perform electrical processing, the link delay is basically constant, so the link delay information is obtained first. Specifically, the link delay information may be obtained through two-way packet interaction, or may be obtained through other methods (such as calculating the link length by OTDR), which will not be further limited here. After obtaining the link delay information, the slave device network node will store the link delay information, and when receiving the synchronization time information periodically sent by the master device network node, according to the synchronization time information and link delay information The time information adjusts the time of the slave device network node itself, so as to achieve time synchronization between the slave device network node and the master device network node.

It should be understood that the transmission method of the synchronization time information can be set according to actual needs, for example, the synchronization time information can be transmitted through a message, or the time information can be transmitted through a pulse signal, and the rising edge or falling edge of the pulse signal is used to indicate the time information, thereby further avoiding time errors caused by message processing.

second embodiment

Referring to FIG. 7, FIG. 7 is a flowchart of a time synchronization method provided by an embodiment of the present invention. The time synchronization method is applied to a second device network node of a synchronous transmission network, as shown in FIG. 7, and includes the following steps:

Step 701: Receive an optical wavelength signal carrying synchronization information sent by the master network node, the optical wavelength signal is a signal transmitted by the transmission path from the master network node to the second device network node, and the transmission path has an independent light wavelength;

Step 702, when the second device network node is an end node of the transmission path, perform time synchronization adjustment according to the synchronization information;

Step 703: When the second device network node is an intermediate device network node of the transmission path, control the forwarding of the optical wavelength signal at the optical layer according to the transmission path.

In this embodiment, the synchronous transmission network includes a master device network node and a second device network node, and the second device network node includes a slave device network node and an intermediate device network node, wherein the slave device network node is used for The node that performs time synchronization with the synchronization information in the transmission path, that is, the end node on the transmission path; the intermediate device network node is a node for forwarding the optical wavelength signal, that is, the intermediate node on the above transmission path. In one transmission path, it may include only the master network node and the slave device network node, or may include the master device network node, the slave device network node and at least one intermediate device network node. When the above-mentioned optical wavelength signal is transmitted to the intermediate device network node, the intermediate network node will forward the optical wavelength signal, and when the optical wavelength signal is transmitted to the slave device network node, the slave device network node will perform synchronization according to the synchronization information in the optical wavelength signal. Time synchronization. For a specific manner of time synchronization, reference may be made to the foregoing embodiments, and details are not repeated here.

Further, the control mode for optical wavelength signal forwarding can be set according to actual needs, and two different implementation solutions will be described in detail below.

For example, referring to FIG. 3, the above-mentioned control of the forwarding of the optical wavelength signal at the optical layer according to the transmission path includes:

Based on the optical combiner and demultiplexer in the second device network node, the optical wavelength signal is passed through in the second device network node, so as to forward the optical wavelength signal to the next network node of the transmission path.

As shown in Figure 3, in this embodiment, an optical multiplexer and demultiplexer and an electrical processing unit are arranged in the second equipment network node, wherein an optical multiplexer and demultiplexer is used to receive the optical wavelength signal sent by the upstream network node or to transmit the optical wavelength signal to the upstream network node The optical wavelength signal is sent, and the other optical multiplexer/demultiplexer is used to receive the optical wavelength signal sent by the downstream network node or send the optical wavelength signal to the downstream network node.

In this embodiment, the optical multiplexer/demultiplexer may be set so that when an optical wavelength signal of a specific optical wavelength is received, the optical wavelength signal is passed through in the second device network node. That is, when an optical wavelength signal sent by an upstream network node is received, the optical wavelength signal can be directly sent to another optical multiplexer/demultiplexer, and another optical multiplexer/demultiplexer directly forwards it to a downstream network node. In addition, the forwarding process of the optical wavelength signal sent by the downstream network node to the upstream network node is the same, and will not be repeated here.

Referring to FIG. 4, the above-mentioned control of the optical wavelength signal forwarding at the optical layer according to the transmission path includes:

Dynamic wavelength scheduling is performed based on an OADM Optical Add-Drop Multiplexer (OADM Optical Add-Drop Multiplexer) device in the second device network node, so that optical wavelength signals are passed through in the second device network node.

As shown in Figure 4, adopt ROADM (Reconfigurable Optical Add-Drop Multiplexer, reconfigurable optical add-drop multiplexer) in the second equipment network node, configure by configuring ROADM, control ROADM to carry out dynamic scheduling of wavelength, make Optical wavelength signals are passed through within the intermediate device network node. It should be understood that the processing of the optical wavelength signal in this embodiment refers to the processing of the optical wavelength signal carrying the synchronization information, and other optical wavelength processing methods can be processed according to existing methods.

In the embodiment of the present invention, receiving the optical wavelength signal carrying the synchronization information sent by the main equipment network node, the optical wavelength signal is a signal transmitted by the transmission path from the main equipment network node to the second equipment network node, and the The transmission path has an independent optical wavelength; when the second device network node is an end node of the transmission path, time synchronization adjustment is performed according to the synchronization information; when the second device network node is an end node of the transmission path When the intermediate device is a network node, the forwarding of the optical wavelength signal at the optical layer is controlled according to the transmission path. Since an independent optical wavelength is set for the synchronization information during the transmission of the synchronization information, the second device network node can directly extract the optical wavelength signal carrying the synchronization information and obtain the synchronization information, thereby shortening the time for obtaining the synchronization information. Reduce the difficulty of obtaining synchronization information and reduce time calculation errors.

third embodiment

Referring to FIG. 8, FIG. 8 is a structural diagram of a time synchronization device provided by the implementation of the present invention. The time synchronization device is applied in a synchronous transmission network and can realize the details of the time synchronization method in the first embodiment and achieve the same effect. As shown in FIG. 8, the time synchronization device 800 includes a path establishment module 801 and a control module 802, wherein:

Path establishment module 801, configured to establish transmission paths from each slave device network node to the master device network node, so that the optical wavelengths corresponding to each of the transmission paths are different optical wavelengths;

The control module 802 is configured to control the synchronization information of each slave device network node to be loaded on the optical wavelength signal corresponding to the optical wavelength, and to transmit on the transmission path, so that the slave device network node can Perform time synchronization adjustments;

Wherein, when the network nodes passed by the transmission path include the master device network node, the slave device network node and at least one intermediate device network node, the control module 802 is also used in the process of transmitting the optical wavelength signal wherein, the intermediate device network node forwards the received optical wavelength signal at the optical layer.

Optionally, the intermediate device network node is specifically configured to: make the optical wavelength signal pass through in the intermediate device network node based on the optical multiplexer/demultiplexer in the intermediate device network node.

Optionally, the intermediate device network node is specifically configured to perform dynamic wavelength scheduling based on the fork multiplexing device in the intermediate device network node, so that optical wavelength signals are directly passed through in the intermediate device network node.

Optionally, the transmission mode of the optical wavelength channel used to transmit the optical wavelength signal includes a single-fiber bidirectional mode.

Optionally, the synchronization information includes a two-way synchronization message, and the two-way synchronization message is used for the slave device network node to calculate the time offset value with the master device network node according to the two-way synchronization message, and perform time Synchronized adjustments.

Optionally, the synchronization information includes synchronization time information sent by the master network node to the slave network node, and the synchronization time information is used for the slave network node to follow the synchronization time information and the transmission path Link delay information for time synchronization adjustment.

In this way, in the embodiment of the present invention, the transmission paths from each slave device network node to the master device network node are established, so that the optical wavelengths corresponding to each of the transmission paths are different optical wavelengths; The synchronization information is loaded on the optical wavelength signal corresponding to the optical wavelength, and transmitted on the transmission path, so that the slave device network node can perform time synchronization adjustment according to the synchronization information; wherein, when the transmission path passes When the network node includes the master device network node, the slave device network node and at least one intermediate device network node, during the transmission of the optical wavelength signal, the intermediate device network node controls the received optical wavelength signal at Optical layer forwarding. Since an independent optical wavelength is set for the synchronization information during the transmission of the synchronization information, the optical wavelength signal carrying the synchronization information can be directly extracted from the device network node, and the synchronization information can be obtained, thereby shortening the time for obtaining the synchronization information and reducing the Difficulty in obtaining synchronization information and reducing time calculation errors. At the same time, when the intermediate device network node of the transmission path receives the optical wavelength signal carrying synchronization information, it does not need to perform photoelectric conversion processing, and directly forwards the optical wavelength signal at the optical layer, thereby avoiding the intermediate device network node from adjusting the optical wavelength signal. The time error introduced by the photoelectric conversion processing of the signal. Therefore, the present invention improves the accuracy of time synchronization, and since errors are only introduced in the master network node and the slave device network node of the transmission path, it can meet the precision requirement of hundreds of nanoseconds.

Fourth embodiment

Referring to FIG. 9, FIG. 9 is a structural diagram of a time synchronization device provided by the implementation of the present invention. The time synchronization device is applied in the second device network node of the synchronous transmission network, and can realize the details of the time synchronization method in the second embodiment, and achieve the same effect. As shown in Figure 9, the time synchronization device 900 includes a receiving module 901, an adjusting module 902 and a forwarding module 903, wherein:

The receiving module 901 is configured to receive an optical wavelength signal carrying synchronization information sent by the master device network node, the optical wavelength signal is a signal transmitted by a transmission path from the master device network node to the second device network node, and the transmission path have independent light wavelengths;

An adjustment module 902, configured to perform time synchronization adjustment according to the synchronization information when the second device network node is an end node of the transmission path;

The forwarding module 903 is configured to control the forwarding of the optical wavelength signal at the optical layer according to the transmission path when the second device network node is an intermediate device network node of the transmission path.

Optionally, the forwarding module 903 is specifically configured to: make the optical wavelength signal pass through in the second equipment network node based on the optical multiplexer and demultiplexer in the second equipment network node, so as to forward the optical wavelength signal to The next network node on the transmission path.

A forwarding module 903, the forwarding module 903 is specifically configured to: control the fork multiplexing device in the second equipment network node to perform wavelength dynamic scheduling, so that the optical wavelength signal is directly passed in the second equipment network node, so that the The optical wavelength signal is forwarded to the next network node on the transmission path.

In the embodiment of the present invention, receiving the optical wavelength signal carrying the synchronization information sent by the main equipment network node, the optical wavelength signal is a signal transmitted by the transmission path from the main equipment network node to the second equipment network node, and the The transmission path has an independent optical wavelength; when the second device network node is an end node of the transmission path, time synchronization adjustment is performed according to the synchronization information; when the second device network node is an end node of the transmission path When the intermediate device is a network node, the forwarding of the optical wavelength signal at the optical layer is controlled according to the transmission path. Since an independent optical wavelength is set for the synchronization information during the transmission of the synchronization information, the second device network node can directly extract the optical wavelength signal carrying the synchronization information and obtain the synchronization information, thereby shortening the time for obtaining the synchronization information. Reduce the difficulty of obtaining synchronization information and reduce time calculation errors.

Those skilled in the art can appreciate that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the scope of the present invention.

Those skilled in the art can clearly understand that for the convenience and brevity of the description, the specific working process of the above-described system, device and unit can refer to the corresponding process in the foregoing method embodiment, which will not be repeated here.

In the embodiments provided in this application, it should be understood that the disclosed devices and methods may be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or May be integrated into another system, or some features may be ignored, or not implemented. In another point, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces, and the indirect coupling or communication connection of devices or units may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment of the present invention.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, each unit may exist separately physically, or two or more units may be integrated into one unit.

If the functions described above are realized in the form of software function units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: various media capable of storing program codes such as U disk, mobile hard disk, ROM, RAM, magnetic disk or optical disk.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (18)

1. a kind of method for synchronizing time, is applied in synchronous transmission network, which is characterized in that including：

Each slave device network node is established to the transmission path of master network node so that each transmission path is corresponding The a length of mutually different optical wavelength of light wave；

The synchronizing information of each slave device network node is controlled to load on the optical wavelength signal of corresponding optical wavelength, and in the biography It is transmitted on defeated path so that the slave device network node can carry out time synchronization adjustment according to the synchronizing information；

Wherein, when the network node that the transmission path is passed through includes the master network node, slave device network node During an at least middleware network node, during the optical wavelength signal transmits, the middleware network node The optical wavelength signal received is forwarded in photosphere.

2. according to the method described in claim 1, it is characterized in that, the middleware network node is to the light that receives Wavelength signals include in photosphere forwarding：

Based on optical multiplexer/demultiplexer in the middleware network node so that the optical wavelength signal is in the middleware network It is led directly in node.

3. according to the method described in claim 1, it is characterized in that, the middleware network node is to the light that receives Wavelength signals include in photosphere forwarding：

The dynamic dispatching of wavelength is carried out based on forking multiple device in the middleware network node so that optical wavelength signal exists It is led directly in the middleware network node.

4. according to the method described in claim 1, it is characterized in that, the optical wavelength is used for transmission the wave of the optical wavelength signal The transmission mode in road includes single fiber bi-directional pattern.

5. method according to any one of claims 1 to 4, which is characterized in that the synchronizing information includes bi-directional synchronization report Text, the bi-directional synchronization message are used to be calculated and main equipment net according to the bi-directional synchronization message for the slave device network node The reporting of network node, and carry out time synchronization adjustment.

6. method according to any one of claims 1 to 4, which is characterized in that the synchronizing information includes master network Information synchronization time that node is sent to slave device network node, information synchronization time are used to supply the slave device network section Point carries out time synchronization adjustment according to the link delay information of information synchronization time and the transmission path.

7. a kind of method for synchronizing time is applied in the second device network node of synchronous transmission network, which is characterized in that packet It includes：

The optical wavelength signal that the transmission of master network node carries synchronizing information is received, the optical wavelength signal is main facility network The signal that the transmission path of network node to the second device network node is transmitted, and the transmission path has independent light Wavelength；

When the second device network node is the endpoint node of the transmission path, the time is carried out according to the synchronizing information Synchronous adjustment；

When the second device network node is the middleware network node of the transmission path, according to the transmission path The optical wavelength signal is controlled to be forwarded in photosphere.

8. the method according to the description of claim 7 is characterized in that described control the light wave long letter according to the transmission path Number include the step of photosphere forwards：

Cause the optical wavelength signal in the second device network node based on optical multiplexer/demultiplexer in the second device network node It is interior straight-through, the optical wavelength signal is forwarded to next network node of transmission path.

9. the method according to the description of claim 7 is characterized in that described control the light wave long letter according to the transmission path Number include the step of photosphere forwards：

Control the dynamic dispatching of forking multiple device progress wavelength in the second device network node so that optical wavelength signal exists It is led directly in the second device network node, the optical wavelength signal is forwarded to next network node of transmission path.

10. a kind of time synchronism apparatus, is applied in synchronous transmission network, which is characterized in that including：

Module is established in path, for establishing each slave device network node to the transmission path of master network node so that each The corresponding a length of mutually different optical wavelength of light wave of the transmission path；

Control module, for controlling the loading of the synchronizing information of each slave device network node in the optical wavelength signal of corresponding optical wavelength On, and be transmitted on the transmit path so that the slave device network node can be carried out according to the synchronizing information Time synchronization adjusts；

Wherein, when the network node that the transmission path is passed through includes the master network node, slave device network node During an at least middleware network node, during the optical wavelength signal transmits, the middleware network node The optical wavelength signal received is forwarded in photosphere.

11. device according to claim 10, which is characterized in that the middleware network node is specifically used for：It is based on Optical multiplexer/demultiplexer in the middleware network node so that the optical wavelength signal is straight in the middleware network node It is logical.

12. device according to claim 10, which is characterized in that the middleware network node is specifically used for, and is based on Forking multiple device carries out the dynamic dispatching of wavelength in the middleware network node so that optical wavelength signal is in the centre It is led directly in device network node.

13. device according to claim 10, which is characterized in that the optical wavelength is used for transmission the optical wavelength signal The transmission mode of radio frequency channel includes single fiber bi-directional pattern.

14. according to claim 10 to 13 any one of them device, which is characterized in that the synchronizing information includes bi-directional synchronization Message, the bi-directional synchronization message is used to be calculated according to the bi-directional synchronization message for the slave device network node and main equipment The reporting of network node, and carry out time synchronization adjustment.

15. according to claim 10 to 13 any one of them device, which is characterized in that the synchronizing information includes main equipment net Information synchronization time that network node is sent to slave device network node, information synchronization time are used to supply the slave device network Node carries out time synchronization adjustment according to the link delay information of information synchronization time and the transmission path.

16. a kind of time synchronism apparatus is applied in the second device network node of synchronous transmission network, which is characterized in that packet It includes：

Receiving module, for receiving the optical wavelength signal that the transmission of master network node carries synchronizing information, the optical wavelength The signal that signal is transmitted by the transmission path of master network node to the second device network node, and the transmission path has There is independent optical wavelength；

Module is adjusted, for when the second device network node is the endpoint node of the transmission path, according to described same It walks information and carries out time synchronization adjustment；

Forwarding module, for when the second device network node be the transmission path middleware network node when, root The optical wavelength signal is controlled to be forwarded in photosphere according to the transmission path.

17. device according to claim 16, which is characterized in that the forwarding module is specifically used for：Based on the second equipment Optical multiplexer/demultiplexer causes the optical wavelength signal to be led directly in the second device network node in network node, by the light Wavelength signals are forwarded to next network node of transmission path.

18. device according to claim 16, which is characterized in that the forwarding module is specifically used for：Control described second Forking multiple device carries out the dynamic dispatching of wavelength in device network node so that optical wavelength signal is in second device network It is led directly in node, the optical wavelength signal is forwarded to next network node of transmission path.