WO2012100698A1

WO2012100698A1 - Method, device, and system for transmitting precision clock synchronization protocol message

Info

Publication number: WO2012100698A1
Application number: PCT/CN2012/070493
Authority: WO
Inventors: 柴斌; 吕欣岩
Original assignee: 华为技术有限公司
Priority date: 2011-01-29
Filing date: 2012-01-17
Publication date: 2012-08-02
Also published as: CN102098154A

Abstract

Disclosed are a method, a device, and a system for transmitting a precision clock synchronization protocol message, which belong to the field of communications. The method comprises: sending a probe request message carrying a random number to a server device through an event message port; receiving a probe response message returned by the server device through the event message port; determining, according to a random number, an address, and a port number carried in the probe response message, an address and a port number of the event message port after network address translation; and notifying the server device of the address and the port number of the event message port after the network address translation in a unicast negotiation process. In the present invention, a client device notifies the server device of the determined address and port number of the event message port after the network address translation, so that the server device initiates an event message accordingly, thereby implementing the transmission of the precision clock synchronization protocol message in an NAT network.

Description

Method, device and system for transmitting precise clock synchronization protocol message

The present invention relates to the field of communications, and in particular, to a method, device, and system for transmitting an accurate clock synchronization protocol message. Background technique

In a communication network, the normal operation of many services requires network clock synchronization, IEEE 1588 (Prec is Ion Clock Synchronization Protocol for Networked Measurement and Control Systems, accurate clock synchronization protocol for network measurement and control systems) as a time Synchronous protocol standards can meet higher precision time synchronization requirements. In communication networks, it is often necessary to implement network clock synchronization by transmitting accurate clock synchronization protocol messages. Among them, the precise clock synchronization protocol message is divided into two types: general message (Genera l Mes sages) and event message (Event Mes sages), and different types of messages use different ports.

In existing unicast networks, when the precise clock synchronization protocol message is carried in IPv4 (Interne t

Pro toco l ver si on 4 , Internet Protocol version 4) When transmitting in the network, before the server device sends an event message to the client device, it needs to determine the IP address and port number used by the client device event message, and then according to the event. The IP address and port number used by the message send an event message to the client device.

In the process of implementing the present invention, the inventors have found that the prior art has at least the following disadvantages: As the number of computers continues to increase, IPv4 address resources cannot meet the needs of network users, and thus NAT (Network Addres s Translating) Conversion) is widely used in various types of IPv4 networks. Since the event message of the client device uses the port through the NAT network, its IP address and port number will be mapped to different public IP and port numbers, resulting in the server device. When the event message is sent to the client device, the IP address and port number of the event message of the client device are not known. Therefore, the transmission mode of the existing accurate clock synchronization protocol message has certain limitations in the NAT network. Sex. Summary of the invention

In order to implement the transmission of the accurate clock synchronization protocol message in the NAT network, the embodiment of the invention provides a method, device and system for transmitting an accurate clock synchronization protocol message. The technical solution is as follows: In one aspect, a method for transmitting an accurate clock synchronization protocol message is provided, where the method includes: And sending, by the event message, the probe request message carrying the random number to the server device by using the port; receiving the probe response message returned by the server device by using the event message, where the probe response message carries the random number and the server device detects Address and port number corresponding to the probe request message;

Determining, according to the random number, address, and port number carried in the probe response message, the address and port number of the event message using the network address translation of the port;

In the unicast negotiation process, the event message is notified to the server device by using the address and port number of the network address translated by the port, so that the server device initiates an event according to the address and port number after the network address translation. Message.

In another aspect, a client device is provided, the client device comprising:

a sending module, configured to send, by using an event message, a probe request message carrying a random number to the server device;

a receiving module, configured to receive a probe response message returned by the server device by using the event message, where the probe response message carries a random number and an address and a port number corresponding to the probe request message detected by the server device;

a determining module, configured to determine, according to a random number, an address, and a port number carried in the probe response message received by the receiving module, an address and a port number of the event message using a network address translated by the port;

a notification module, configured to notify the server device that the event message determined by the determining module uses a network address translated address and a port number in the unicast negotiation process, so that the server device is configured according to the The address and port number after the network address translation initiates an event message.

A server device is also provided, the server device comprising:

a receiving module, configured to receive a probe request message that carries a random number sent by the client device by using an event message;

a returning module, configured to return, by using the event message, a probe response message to the client device, where the probe response message carries a random number and an address and a port corresponding to the probe request message detected by the server device number;

And an obtaining module, configured to obtain, during the unicast negotiation process, the event message notified by the client device, using an address and a port number converted by the network address of the port;

And a sending module, configured to initiate an event message according to the address and port number converted by the network address obtained by the acquiring module. A system for transmitting an accurate clock synchronization protocol message is also provided, the system comprising: a client device and a server device;

The client device is the client device, and the server device is the server device. The beneficial effects of the technical solutions provided by the embodiments of the present invention are:

After the client device determines that the event message uses the address and port number of the port after the network address translation, it notifies the server device, so that the server device initiates an event message accordingly, thereby realizing an accurate clock synchronization protocol message in the NAT network. transmission. DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described. It is obvious that the drawings in the following description are only some embodiments of the present invention. Other drawings may also be obtained from those of ordinary skill in the art in view of the drawings.

1 is a flowchart of a method for transmitting an accurate clock synchronization protocol message according to Embodiment 1 of the present invention; FIG. 2 is a flowchart of a method for transmitting an accurate clock synchronization protocol message according to Embodiment 2 of the present invention; A schematic diagram of the structure of the client device provided;

4 is a schematic structural diagram of a server device according to Embodiment 4 of the present invention;

FIG. 5 is a schematic structural diagram of a system for transmitting an accurate clock synchronization protocol message according to Embodiment 5 of the present invention. detailed description

The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

Embodiment 1

Referring to FIG. 1, this embodiment provides a method for transmitting an accurate clock synchronization protocol message. The method is as follows:

1 01: Sending, by using an event message, a probe request message carrying a random number to a server device by using a port;

1 02: The receiving server device uses the probe response message returned by the port through the event message, where the probe response message carries the random number and the address and port number corresponding to the probe request message detected by the server device; 1 03: Determine, according to the random number, address, and port number carried in the probe response message, the address and port number of the event message using the network address translated by the port;

1 04: In the unicast negotiation process, the event message is notified to the server device by the address and port number of the port after the network address translation, so that the server device initiates an event message according to the address and port number converted by the network address.

The address and the port number of the event message using the network address translation of the event message are determined according to the random number, the address, and the port number carried in the probe response message, and specifically include:

After determining that the random number carried in the probe response message is consistent with the random number carried in the probe request message, comparing the address and port number carried in the probe response message with the address and port number when sending the probe request message;

If they are inconsistent, the address and port number carried in the probe response message are determined as the address and port number of the event message using the network address translation of the port.

In the unicast negotiation process, the event message is notified to the server device by using the address and port number of the port after the network address translation, including:

The event message unicast negotiation request is sent to the server device through the general message using the port. The event message unicast negotiation request carries the event message using the address and port number of the port after the network address translation, so that the server device obtains the unicast negotiation request according to the event message. The event message uses the address and port number of the port after the network address translation.

Specifically, the event message unicast negotiation request uses the address and port number of the port after the network address translation by using the extended cell carrying event message.

The method provided by the embodiment, after the client device determines that the event message uses the address and port number of the port after the network address translation, notifies the server device of the event, so that the server device initiates an event message accordingly, thereby realizing an accurate clock. The synchronization protocol message is transmitted in the NAT network. Embodiment 2

This embodiment provides a method for transmitting an accurate clock synchronization protocol message. Before the accurate clock synchronization protocol message is transmitted, the method uses the customized probe message to enable the client device to know whether a NAT exists in the network, and learns the event. After the message uses the NAT-transformed address and port number, it sends it to the server device, so that the server device initiates an event message accordingly. The specific detection message is not limited in this embodiment. The handshake request message and the handshake response message are used as an example for description. Referring to FIG. 2, the process of the method provided in this embodiment is specifically as follows: 201: The client device sends a handshake request message carrying a random number (Handshake.Req) to the server device by using an event message.

Specifically, the event message uses port 319 of the UDP (User Datagram Protocol), and the general message uses port 320 of UDP. Therefore, in this step, the client device sends the port 319 to the server device. A handshake request message carrying a random number.

For details on the role of the random number, refer to the description in the following step 202. This embodiment does not limit the specific random number carried in the handshake request message. In addition, the handshake request message carries a random number, and like other accurate clock synchronization protocol messages, the handshake request message also needs to carry the source IP address, the source port number of the handshake request message, and the handshake request message to be sent to. Destination IP address and destination port number. In this step, the source IP address carried in the handshake request message is the private network IP address of the client device, the source port number is the port number 319 of the event message using the port, and the destination IP address is the IP address of the server device. The destination port number is also 319. The role of the handshake request message is used to maintain the channel between the client device and the server device in addition to the channel between the client and the server in the NAT subnet.

202: The client device receives a handshake response message (Handshake.Resp) returned by the server using the event message, where the handshake response message carries a random number and a source IP address and a port number of the handshake request message detected by the server device.

The source IP address, the source port number, and the destination IP address and destination port number to which the handshake response message is to be sent are also required to be carried in the handshake response message. For the step, the source IP address carried in the handshake response message is the IP address of the server device, the source port number is 319, and the destination IP address is the address of the handshake request message detected by the server device, and the destination port number is the server device. The port number of the detected handshake request message. If the address and port number of the handshake request message detected by the server device are different from the address and port number of the handshake request message sent by the client device, the NAT exists between the client device and the server device. Therefore, the client device according to the handshake The random number, address, and port number carried in the response message can be used to know whether NAT exists in the network.

In a specific implementation, the client device first determines whether the random number carried in the handshake response message is consistent with the random number carried in the handshake request message sent by the client, and if the agreement is consistent, the handshake response message is sent to the handshake request message sent by the client device. Corresponding response message. On the basis of this, the client device further compares the address and port number carried in the handshake response message with the address and port number when the probe request message is sent. If they are consistent, it is determined that there is no NAT in the network. Indicates that there is a NAT in the network, and also indicates the address and port of the handshake request message sent by the client device. The number is changed by the network address, and the address and port number of the handshake request message detected by the server device is the translated address and port number, so the address and port number carried in the handshake response message can be determined as an event message. Use the address and port number of the port after the network address translation.

After the client device learns that the event message uses the port to be network address translated, in order to enable the server device to send the event message normally, the client device may use the address of the port through the network address translation in the unicast negotiation process. The port number is notified to the server device. For details, see the subsequent steps.

203: The client device sends an Announce message unicast negotiation request to the server device, where the Announce message unicast negotiation request can be REQUEST-UNICAST-TRANSMI SSION ( Ann ); specifically, the client device can pass through port 319 ( Event message using port) send this

The Announce message unicast negotiation request may also send the Announce message unicast negotiation request through port 320 (general message use port). This embodiment does not limit the port used by the client to send the Announce message unicast negotiation request. Regardless of which port is used for sending, the Announce message unicast negotiation request also carries the source IP address (the private IP address of the client device), the source port number (320 or 319), and the destination IP address (the IP address of the server device). And the destination port number (320 or 319).

204: The client device receives an Announce message unicast negotiation response returned by the server device, where the Announce message unicast negotiation response may be GRANT_UNICAST_TRANSMISS ION ( Ann );

In the same step 202, the Announce message unicast negotiation response returned by the server device also carries the address and port number of the Announce message unicast negotiation request detected by the server device, and if there is NAT, the Announce message detected by the server device The address and port number of the unicast negotiation request are inconsistent with the address and port number of the Announce message unicast negotiation request sent by the client device.

205: The client device receives an Announce message unicast by the server device.

Specifically, the Announce message carries information such as an optimal clock priority, a time level, and a time precision, so that the client device can perform clock source selection according to the information carried in the received Announce message.

206: The client device sends a Sync (Synchronize) message unicast negotiation request to the server device by using a general message using a port, and the Sync message unicast negotiation request may be REQUEST_UNICAST_TRANSMISSION (Sync);

The client device sends a Sync message unicast negotiation request to the server device to request the server device to unicast the Sync message, to generate and interact time information according to the Sync message, and to synchronize the time. However, since the Sync message belongs to the event message, the server device needs to use the port through the event message. (Port 319) is initiated. If there is a NAT in the network, the server does not determine in advance that the event message uses the address and port number of the port after the network address translation. In this regard, the client device learns that the event message uses the port in step 202. After the address and port number of the network address translation, the device can be notified to the server device during the unicast negotiation interaction.

In this embodiment, the specific notification mode is not limited. The address and port number of the event message using the network address translation port are used as an example in the Sync message unicast negotiation request. In specific implementation, the Sync message may be used in the Sync message. The extended cell ORGANIZATION_EXTENSION, and the extended cell carries the event message using the address and port number cell of the port after the network address translation.

207: The client device receives a Sync message unicast negotiation response returned by the server device, where the Sync message unicast negotiation response may be GRANT_UNICAST_TRANSMISS ION (Sync);

For this step, the Sync message unicast negotiation response returned by the server device also carries the source IP address (the private IP address of the server device), the source port number (319), and the destination IP address (the IP address of the Sync message unicast negotiation request). Address) and destination port number (319).

208: The client device receives a Sync message that the server device uses the port unicast through the event message. Specifically, before the server device uses the port unicast Sync message by using the event message, the client device has notified the server device of the event message using the port address and port number converted by the network address in the Sync message unicast negotiation process. Therefore, when the server device uses the port unicast Sync message through the event message, the destination IP address and port number carried by the server device are the address and port number converted by the network address, so the Sync message can be accurately sent to the client device. The transmission of Sync messages in the NAT network is implemented.

It should be noted that, in step 206, the event message determined by the client device is notified to the server device by using the address and port number of the port after the network address translation. Therefore, the foregoing steps 201 and 202 may be performed in the above order. Executing before step 203, it may also be performed after step 205 and before step 206. The implementation is performed before the step 203 to keep the same with the existing protocol, and the aging of the NS is not limited.

The method provided by the embodiment, after the client device determines that the event message uses the address and port number of the port after the network address translation, notifies the server device of the event, so that the server device initiates an event message accordingly, thereby realizing an accurate clock. The synchronization protocol message is transmitted in the NAT network. Embodiment 3 The present embodiment provides a client device, which is used to perform the method steps performed by the client device in the first embodiment and the second embodiment. Referring to FIG. 3, the client device includes:

The sending module 301 is configured to send, by using an event message, a probe request message carrying a random number to the server device by using the port;

The receiving module 302 is configured to receive a probe response message returned by the server device by using an event message, where the probe response message carries a random number and an address and a port number corresponding to the probe request message detected by the server device;

The determining module 30 is configured to determine, according to the random number, address, and port number carried in the probe response message received by the receiving module 302, the address and port number of the event message using the network address translated by the port; the notification module 304 is configured to perform unicast During the negotiation, the event message determined by the module 303 is notified to the server device by using the address and port number of the port after the network address translation, so that the server device initiates an event message according to the address and port number converted by the network address.

The determining module 303 is specifically configured to: when the random number carried in the probe response message is consistent with the random number carried in the probe request message, compare the address and the port number carried in the probe response message with the sending of the probe request message. If the address and port number are the same, if the number is inconsistent, the address and port number carried in the probe response message are determined as the address and port number of the event message using the network address translation port.

The notification module 304 is configured to send an event message unicast negotiation request to the server device by using the general message using the port, and the event message unicast negotiation request carries the address and port number of the event message using the network address translation port, so that the server device According to the event message unicast negotiation request, the event message is obtained by using the address and port number of the port after the network address translation.

The client device provided in this embodiment notifies the server device by using the address and port number after the network address is translated by using the port, so that the server device initiates an event message according to the event, thereby realizing accurate clock synchronization. The transmission of protocol messages in a NAT network. Embodiment 4

The embodiment of the present invention provides a server device, which is used to perform the method steps performed by the server device in the first embodiment and the second embodiment. Referring to FIG. 4, the server device includes: a receiving module 401, configured to receive a client. The end device sends a probe request message carrying a random number sent by the port through the event message;

The returning module 402 is configured to return a probe response to the client device by using the event message using the port. The probe response message carries the random number and the address and port number corresponding to the probe request message detected by the server device;

The obtaining module 40 is configured to obtain an event message notified by the client device during the unicast negotiation process, using an address and a port number of the port after the network address translation;

The sending module 404 is configured to initiate an event message according to the address and port number converted by the network address obtained by the obtaining module 403.

The obtaining module 403 is specifically configured to receive an event message unicast negotiation request sent by the client device through the general message using the port, and the event message unicast negotiation request carries the address and port number of the event message using the port after the network address translation. According to the event message unicast negotiation request, the event message is obtained by using the address and port number of the port after the network address translation.

The server device provided by the embodiment sends an event message according to the address and the port number converted by the network address after the event message notified by the client device is obtained, thereby implementing an accurate clock synchronization protocol message in the NAT network. Transmission. Embodiment 5

This embodiment provides a system for transmitting an accurate clock synchronization protocol message. Referring to FIG. 5, the system includes: a client device 501 and a server device 502;

The client device 501 is the client device provided in the foregoing Embodiment 3;

The server device 502 is the server device provided in the above fourth embodiment.

In summary, the system provided by the embodiment, after the client device determines that the event message uses the address and port number of the port after the network address translation, notifies the server device to enable the server device to initiate an event message according to the event, thereby implementing the event message. The transmission of precise clock synchronization protocol messages in a NAT network. It should be noted that, when the client device and the server device provided by the foregoing embodiments transmit the accurate clock synchronization protocol message, only the division of the foregoing functional modules is illustrated. The functional modules may be implemented in hardware or in software. The above functional modules may be implemented in combination or further split into sub-modules. In the inter-application, the above function assignment can be completed by different functional modules as needed, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. In addition, the client device, the server device, the system for transmitting the accurate clock synchronization protocol message, and the method for transmitting the accurate clock synchronization protocol message are in the same concept, and the specific implementation process is described in the method embodiment. Narration. The serial numbers of the embodiments of the present invention are merely for the description, and do not represent the advantages and disadvantages of the embodiments. All or part of the steps in the embodiment of the present invention may be implemented by using software, and the corresponding software program may be stored in a readable storage medium, such as an optical disk or a hard disk.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., which are within the spirit and scope of the present invention, should be included in the protection of the present invention. Within the scope.

Claims

Claim

A method for transmitting an accurate clock synchronization protocol message, the method comprising: transmitting, by using an event message, a probe request message carrying a random number to a server device by using an event message; receiving, by the server device, the event message by using the event message a probe response message returned by the port, where the probe response message carries a random number and an address and a port number corresponding to the probe request message detected by the server device;

The method according to claim 1, wherein the determining, according to the random number, the address, and the port number carried in the probe response message, the address and port number of the event message using the network address translated by the port Specifically, including:

After determining that the random number carried in the probe response message is consistent with the random number carried in the probe request message, comparing an address and a port number carried in the probe response message with an address when sending the probe request message And whether the port number is consistent;

If they are inconsistent, the address and port number carried in the probe response message are determined as the address and port number of the event message using the port translated by the network address.

The method according to claim 1, wherein, in the unicast negotiation process, the event message is notified to the server device by using a network address translated address and a port number of the port, specifically:

Sending an event message unicast negotiation request to the server device by using a general message using a port, where the event message unicast negotiation request carries the address and port number of the event message using the network address translation of the port, so that the server device Obtaining, according to the event message unicast negotiation request, an address and a port number of the event message using the network address translation of the port.

The method according to claim 1, wherein the event message unicast negotiation request carries the address and port converted by the network address using the event message by using the extended cell. number.

A client device, the client device comprising:

The client device according to claim 5, wherein the determining module is configured to: determine that the random number carried in the probe response message is consistent with a random number carried in the probe request message And comparing the address and the port number carried in the probe response message with the address and the port number when the probe request message is sent; if not, determining the address and the port number carried in the probe response message as The event message uses the address and port number of the port after the network address translation.

The client device according to claim 5, wherein the notification module is configured to send an event message unicast negotiation request to the server device by using the general message using port, the event message list The broadcast negotiation request carries the address and port number of the event message using the network address translation of the port, so that the server device obtains the event message using the port after the network address is translated according to the event message unicast negotiation request. Address and port number.

A server device, wherein the server device comprises:

a receiving module, configured to receive a probe request message that carries a random number sent by the client device by using an event message; a returning module, configured to return, by using the event message, a probe response message to the client device, where the probe response message carries a random number and an address and a port corresponding to the probe request message detected by the server device number;

And a sending module, configured to initiate an event message according to the network address translated address and the port number obtained by the acquiring module.

The server device according to claim 8, wherein the acquiring module is configured to receive an event message unicast negotiation request sent by the client device by using the general message using port, the event message The unicast negotiation request carries the address and port number of the event message using the network address translation of the port, and obtains the address and port number of the event message using the network address translation according to the event message unicast negotiation request. .

A system for transmitting a precise clock synchronization protocol message, the system comprising: a client device and a server device;

The client device is the client device according to any one of claims 5 to 7, and the server device is the server device according to claim 8 or claim 9.