WO2015024477A1

WO2015024477A1 - Routing update method and device

Info

Publication number: WO2015024477A1
Application number: PCT/CN2014/084418
Authority: WO
Inventors: 孔敏达; 袁春; 缪众林; 仲建锋
Original assignee: 中兴通讯股份有限公司
Priority date: 2013-08-19
Filing date: 2014-08-14
Publication date: 2015-02-26
Also published as: CN104426775A; CN104426775B

Abstract

Embodiments of the present invention disclose a routing update method and device. The method is executed in a switching device: step 1, according to received routing information, establishing a routing update table; step 2, according to the routing entries in the routing update table, performing consistent synchronization; step 3, upon the completion of synchronization, clearing the routing update table, and repeating step 1.

Description

Method and device for implementing route update

Technical field

The present invention relates to the field of computer communication technologies, and in particular, to a method and an apparatus for implementing route update.

Background technique

The switching system is used to complete high-speed and high-capacity information exchange of network packets. The switching system consists of a switching access device and a switching network, which are connected by a link. As shown in FIG. 1, the switching access device is divided into two functional roles: a source switching access device 101 and a destination switching access device 102. The switching network is composed of a switching network element 103. The source switching access device 101 receives the network packet and cuts it into a cell. The cell is a transmission form unique to the switching system and is transmitted to the switching network. The switching network completes the delivery and copying of cells. The destination switching access device 102 receives the cells from the switching network and reassembles them into network messages and sends them out. Physically, a switched access device is both a source switching access device and a destination switching access device. What the switching system does is the exchange of network messages from one switching access device to another or multiple switching access devices.

The routing information refers to the exchanges between the switching devices of the primary switching device and the destination switching access device through which links the cells in the switching system can complete. The routing table is a collection of routing information, including routing information from the switching device of the current level to all destination switching access devices.

The routing table can be established and updated by self-routing. Self-routing means that the switching access device and the switching network element in the switching system establish and update the routing table by transmitting the cells carrying the routing information. The self-routing establishes and updates a routing table according to the manner in which the destination switching device is a switching network element and a source switching device. As shown in FIG. 2, the process specifically includes: Step 201: The destination switching access device sends routing information to the switch. a network element; Step 202, the switching network element establishes its routing table according to the routing information; Step 203: The switching network element sends routing information to the source switching access device; Step 204, the source switching access device establishes its routing table according to the routing information. . For the same reason, after the roles exchange between the destination switching access device and the source switching access device are performed, according to the above process, all switching devices in the switching system establish a routing table, and data exchange can be performed. A single-level networking switching system, as shown in FIG. 3, is composed of two switching access devices and two switching network elements, and the switching access device chip IDs are respectively configured as 0# and 1#. Because the chip ID of the 1# switching access device changes for some reason, the routing entries of the 1# switching access device in the routing table originally established by the switching network cannot be updated because the self-routing is established by receiving routing information. Update the routing table. After the chip ID is changed, the switching network no longer receives the routing information of the 1# switching access device, and the routing entries corresponding to the 1# switching access device in the routing table cannot be cleared, that is, the routing table. Cannot be updated correctly. After the error occurs, the switching network sends the actual unreachable routing information (such as the routing information of the 1# switching access device at this time) as reachable routing information to all switching access devices, causing an error. This error occurs not only in the networking structure shown in FIG. 3, but also in the networking structure as shown in FIGS. 4 and 5.

The traditional processing method is to intervene through software, that is, after the switching access device chip ID changes, the routing table is forced to be cleared by software intervention. This method is slow to process, does not guarantee stability and reliability during data exchange, and requires additional CPU resources.

Summary of the invention

The technical problem to be solved by the embodiments of the present invention is to provide a method and a device for implementing route update, which ensure stability and reliability in the data exchange process.

The implementation of the routing update is performed in a switching device, including:

Step 1: Establish a route aging table according to the received routing information.

Step 2: Perform consistency synchronization on the routing table based on the routing entries in the route aging table. Step 3: After the synchronization is complete, clear the route aging table to 0. Repeat step 1.

Preferably, the received routing information is cached during the execution of the consistency synchronization operation in step 2 and the clearing operation in step 3, and is used to establish a route aging table when step 1 is performed.

Preferably, the method further includes:

Set the execution time for steps 1~3. In the order of steps 1~3, the corresponding steps are executed in sequence at the end of each set execution time.

Preferably, the switching device comprises: a switching access device and/or a switching network element; In the routing table and the route aging table, the correspondence between the destination switching access device chip ID and the available link of the switching device that can reach the destination switching access device is recorded.

Preferably, the method is applied to a switching system in which the switching access device is connected to the switching network element, and a switching system interconnected by the switching access device.

The embodiment of the present invention further provides an apparatus for implementing a route update, which is located in a switching device, where the device includes:

a route establishment module, configured to establish a route aging table according to the received routing information; and a route update module configured to perform consistent synchronization on the routing table based on the routing entry in the route aging table;

The route aging module is configured to clear the route aging table after the synchronization is completed, and invoke the route establishment module.

Preferably, the device further includes:

The route cache module is configured to buffer the received route information and send it to the route establishment module during a period in which the route update module performs the consistency synchronization operation and the route aging module performs the clear operation.

Preferably, the device further includes:

The route aging control module is configured to set an execution duration for the route establishment module, the route update module, and the route aging module respectively, in the order of the route establishment module, the route update module, and the route aging module, in each set At the end of the execution time, the corresponding module is called in turn.

Preferably, the switching device comprises: a switching access device and/or a switching network element;

In the routing table and the route aging table, the correspondence between the destination switching access device chip ID and the available link of the switching device that can reach the destination switching access device is recorded.

Preferably, the apparatus is applied to a switching system in which the switching access device is connected to the switching network element, and a switching system interconnected by the switching access device.

Embodiments of the present invention also provide a computer program comprising program instructions that, when executed by a switching device, cause the switching device to perform the method described above. Embodiments of the present invention also provide a carrier carrying the above computer program.

The method and device for implementing the route update according to the embodiment of the present invention can be updated by routing aging to ensure the stability and reliability of the switching system. Compared with related technologies, although the route aging function adds extra system resource overhead, the system resources consumed occupy only a small part and can be ignored. If the device in the embodiment of the present invention is implemented by hardware, the route update speed is faster than the related technology, and the CPU resources are not occupied. BRIEF abstract

Figure 1 is a schematic structural diagram of a switching system;

2 is a schematic diagram of a process of self-routing in accordance with a manner in which a switching access device, a switching network element, and a source switching device are switched;

Figure 3 is a schematic structural diagram of a single-stage networking switching system;

Figure 4 is a schematic structural diagram of a CLOS networking switching system;

Figure 5 is a schematic structural diagram of a MESH networking switching system;

6 is a flowchart of a method for implementing route update according to a first embodiment of the present invention;

7 is a schematic structural diagram of an apparatus for implementing route update according to a second embodiment of the present invention;

8 is a schematic structural diagram of a switching system according to an application example of the present invention;

9 is a schematic diagram of a routing table of a switching network element according to an application example of the present invention;

10 is a schematic diagram of a routing table of a switching access device according to an application example of the present invention;

11 is a schematic diagram of a route aging processing procedure of an application instance according to the present invention;

FIG. 12 is a schematic diagram showing a three-stage conversion relationship of an aging process according to an application example of the present invention.

Preferred embodiment of the invention

The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. The features in the embodiments and the embodiments of the present application may be arbitrarily combined with each other without conflict. A first embodiment of the present invention, a method for implementing route update, as shown in FIG. 6, performs the following steps in a switching access device and/or a switching network element:

Step S101: Establish a route aging table according to the received routing information.

In this step, because the switching access device or the switching network element is in the network, when the routing is established, the switching access device itself may have two functional roles: a source switching access device and a destination switching access device, and one switching The access device can receive routing information sent by the corresponding destination switching access device through all its available links. In addition, according to the basic functions of the switching network element, a switching network element can also receive routing information sent by the corresponding switching access device through all available links.

Step S102: Perform consistency synchronization on the routing table based on the routing entry in the route aging table. In this step, in the routing table and the route aging table, the correspondence between the destination switch access device chip ID and the available link of the local switching device that can reach the destination switching access device is recorded. Here, the switching device may be a switching access device or a switching network element.

Step S103: After the synchronization is completed, clear the route aging table, and repeat step S101. For the use of the routing table, the embodiment of the present invention follows the usage mode of the prior art, and the switching device (ie, the switching access device or the switching network element) periodically sends the routing information in the routing table through all available links.

Preferably, the routing information sent via all available links may also be generated during the period of performing the consistency synchronization operation in step S102 and the clearing operation in step S103, but cannot be used for immediate establishment or Updating the routing entries in the routing aging table, in order to further improve the stability and reliability of the switching system, the routing information received through all available links received during the period is cached, and is used to perform step S101. Establish a route aging table. Those skilled in the art should understand that all available links refer to all available links of the switching access device or the switching network element to the outside world.

Preferably, in the implementation method of the route update in this embodiment, the execution time length may be separately set in steps S101 and S103, and the corresponding execution time length is sequentially called according to the state machine in the order of steps S101 and S103. The steps are performed.

The implementation method of the route update in this embodiment may be applied to a switching system in which a switching access device is connected to a switching network element, and a switching system interconnected by the switching access device. The second embodiment of the present invention is related to the implementation method of the route update in the first embodiment. The embodiment is a device for implementing route update, which is located in a switching access device and/or a switching network element, as shown in FIG. 7. As shown, the includes:

The route establishment module 100 is configured to establish a route aging table according to the received routing information. Wherein, because the switching access device or the switching network element is in the network, when establishing the route, the switching access device itself may have two functional roles: the source switching access device and the destination switching access device, and one switching access The route establishment module 100 in the device can receive routing information sent by the corresponding destination switching access device through all available links thereof. In addition, according to the basic functions of the switching network element, the route establishing module 100 in a switching network element can also receive routing information sent by the corresponding switching access device through all available links thereof.

The routing update module 200 is configured to perform consistent synchronization on the routing table based on routing entries in the routing aging table.

The mapping between the destination switching access device chip ID and the available link of the local switching device that can reach the destination switching access device is recorded in the routing table and the routing aging table. Here, the switching device may be a switching access device or a switching network element.

The route aging module 300 is configured to clear the route aging table to the call routing establishment module 100 after the synchronization is completed.

For the use of the routing table, the embodiment of the present invention follows the usage mode of the prior art, and the switching device (ie, the switching access device or the switching network element) periodically sends the routing information in the routing table through all available links.

Preferably, since the routing update module 200 performs the consistency synchronization operation and the routing aging module 300 performs the clearing operation, routing information sent via all available links may also be generated, but this time cannot be used immediately. The device for implementing the route update in this embodiment further includes:

The route cache module 400 is configured to receive the received all available links during the period in which the routing update module 200 performs the consistency synchronization operation and the route aging module 300 performs the clear operation. The sent routing information is cached and sent to the route establishment module 100 for establishing a route aging table.

Preferably, the device further includes:

The route aging control module 500 is configured to set an execution duration for the route establishment module 100, the route update module 200, and the route aging module 300, and according to the state machine, according to the slave route establishment module 100, the route update module 200, and the route aging. The order of the modules 300, in turn, calls the corresponding module run at the end of each set execution time.

The apparatus for implementing route update in this embodiment may be applied to a switching system in which a switching access device is connected to a switching network element, and a switching system in which the switching access device is interconnected.

Embodiments of the present invention also provide a computer program comprising program instructions that, when executed by a switching device, cause the switching device to perform the method described above.

Embodiments of the present invention also provide a carrier carrying the above computer program.

An application example of the present invention will be described below based on the above embodiment.

The switching system of this application example is composed as shown in FIG. 8, and includes two switching access devices 801.

802 and a switching network element 803. The switching access device 801 has a chip ID configured to 0 (hereinafter referred to as a zero-number switching access device), and the switching access device 802 has a chip ID configured to 1 (hereinafter referred to as a switching device No. 1). The links 0, 1, and 2 of the switching access device 801 are respectively connected to the links 0, 2, and 4 of the switching network element, and the links 0 and 1 of the switching access device 802 are respectively connected to the links 1 and 3 of the switching network element. However, in practice, the connection relationship between the switching access device and the switching network element may be arbitrary.

Step 001: The destination switching access device sends routing information to all available links, and notifies the switching network element that the switching access device can reach the destination switching access device.

Step 002: The switching network element establishes its routing table by receiving routing information. As shown in FIG. 9( a ), the index 901 is the destination switching access device chip ID, and the data bit width 902 is the switching network element and the switching access device. The maximum number of possible links, the content 903 is the bit map of the link of the currently reachable destination switching access device.

Step 003: The switching network element sends routing information to all available links to notify the source switching access device of which destination switching access devices can reach through the links. Step 004: The source switching access device receives the routing information to establish a routing table, and the routing table established in the current switching access device No. 0 and the switching access device No. 1 is as shown in FIG. 10( a ).

Step 005, No. 1 exchange access device for some reason, its chip ID is modified to 2, modified to be called the number 2 exchange access device.

If there is no route aging process, the process proceeds to step 006 after step 005. If the route aging process is performed, the process proceeds to step 106.

Step 006: The switching network element receives the routing information sent by the switching access device No. 2, and establishes a routing table as shown in Figure 9 (b). It can be seen from the routing table that the switching network element can still send a cell to the No. 1 switching access device, that is, the originally established routing table cannot be corrected.

Step 007: The switching network element sends routing information to the source switching access device, and the source switching access device is established as shown in FIG. 10(b), and the routing update process ends. It can be seen from the routing table that the 0th switching access device can still exchange the cell to the No. 1 switching access device, and the originally established routing table cannot be corrected; the No. 2 switching access device can also exchange the cell to In the switching access device No. 1, the switching network element transmits the wrong routing information to the source switching access device.

Step 106: Under the control of the route aging controller, all the switching access devices and the routing table of the switching network element periodically perform route aging processing, and all routing table contents are cleared.

Figure 11 is a schematic diagram of the foregoing route aging process, which mainly involves a routing table, a routing aging table, and a route aging controller, which are located in each switching access device and switching network element.

The routing table stores the routing information of the switching device of the current level (the switching device here refers to: the switching network element or the switching access device), and provides available links for cell transmission and replication. The routing table is periodically updated under the control of the route aging controller. At the same time, the routing table sends the routing information of the local level to the upstream switching device.

The route aging table receives the routing information of the downstream switching device, establishes the local routing table, performs periodic clearing and updating under the control of the route aging controller, and the routing aging table updates the correct routing information after aging update to the routing. Go in the table. The destination switching device that is reachable in the process of route establishment and update is called the downstream switching device, and the source switching device is called the upstream switching device.

The route aging controller divides the route aging process into three phases. As shown in FIG. 12, the route establishment phase 701, the route update phase 702, and the route aging phase 703. These three stages are looped, In the route construction phase, the route aging table is established by receiving the routing information. In the route update phase, the routing information in the routing aging table is updated to the routing table. In the aging phase of the route, the routing aging table is cleared.

Step 107: After the switching access device is disconnected from the switching system, the switching network element does not continue to receive the routing information sent by the switching access device, and the routing table re-established by the switching network element is as shown in FIG. 9(c). The switching network element can only send cells to the switching access devices No. 0 and No. 2, and the routing table is correctly updated.

Step 108: The switching network element sends the correct updated routing information to the source switching access device, and the routing table re-established by the switching access device is shown in FIG. 10(c), and the switching network element no longer transmits the wrong routing information and routes. The update process ends.

The embodiment of the invention provides a design idea and a method, which can solve the problem that the routing table cannot be correctly updated when self-routing, and ensures the stability and reliability in the data exchange process. The embodiment of the invention implements the correct update of the routing table by adding route aging processing in the process of routing update. That is, the switching access device or the switching network element establishes a routing table by receiving routing information, and periodically clears the routing table. After the processing is completed, the routing table is re-established by receiving new routing information. The old routing information is cleared in the process of aging the route, ensuring that the incorrect routing information is not transmitted to the upstream switching device, and that the cells are not incorrectly delivered to the downstream switching device.

The technical means and functions of the present invention for achieving the intended purpose can be more deeply and specifically understood by the description of the specific embodiments. However, the accompanying drawings are only for the purpose of reference and description, and are not intended to be Limit it.

One of ordinary skill in the art will appreciate that all or a portion of the steps described above can be accomplished by a program that instructs the associated hardware to be stored in a computer readable storage medium, such as a read only memory, disk or optical disk. Optionally, all or part of the steps of the foregoing embodiments may also be implemented by using one or more integrated circuits. Accordingly, each module/unit in the foregoing embodiment may be implemented in the form of hardware, or may use software functions. The form of the module is implemented. The invention is not limited to any specific form of combination of hardware and software.

Industrial applicability The method and device for implementing route update according to the embodiment of the present invention are updated by route aging. The stability and reliability of the switching system can be ensured.

Claims

claims

1. A method for implementing route update, including performing the following steps in a switching device: Step 1. Establish a route aging table based on the received routing information;

Step 2: Consistently synchronize the routing table based on the routing table entries in the routing aging table; Step 3: After the synchronization is completed, clear the routing aging table and repeat step 1.

2. The implementation method of routing update according to claim 1, wherein the received routing information is cached during the time period during which the consistency synchronization operation in step 2 and the clearing operation in step 3 are performed, and the cached routing information is cached. The routing information is used to establish the routing aging table when performing step 1.

3. The method for implementing routing update according to claim 1, the method further comprising: setting the execution duration for steps 1 to 3 respectively, and following the order of steps 1 to 3, at the end of each set execution duration Call the corresponding steps in sequence.

4. The method for implementing route update according to claim 1, wherein the switching device includes: a switching access device and/or a switching network element;

In the routing table and the route aging table, what is recorded is the corresponding relationship between the chip identification of the destination switching access device and the available link on the switching device that can reach the destination switching access device.

5. The method for implementing route update according to any one of claims 1 to 4, wherein the method is applied to a switching system in which a switching access device is connected to a switching network element, and a switching system interconnected by a switching access device. system.

6. A device for implementing route update, located in a switching device. The device includes: a route establishment module, which is configured to establish a route aging table based on the received routing information; a route update module, which is configured to establish a route aging table based on the route aging table. The routing table entries in the routing table are consistently synchronized; and

The route aging module is configured to clear the route aging table and call the route establishment module after synchronization is completed.

7. The device for implementing route update according to claim 6, the device further comprising: a route cache module configured to perform a consistency synchronization operation in the route update module and a clearing operation in the route aging module. Within the time period, the received routing information is cached, Sent to the route establishment module.

8. The device for implementing route update according to claim 6, the device further comprising: a route aging control module, which is configured to set settings for the route establishment module, the route update module and the route aging module respectively. The execution duration is in the order from the route establishment module, through the route update module, to the route aging module, and the corresponding modules are sequentially called to run at the end of each set execution duration.

9. The device for implementing route update according to claim 6, wherein the switching device includes: a switching access device and/or a switching network element;

Both the routing table and the route aging table record the correspondence between the chip ID of the destination switching access device and the available links on the switching device that can reach the destination switching access device.

10. The device for implementing route update according to any one of claims 6 to 9, wherein the device is applied to a switching system in which a switching access device is connected to a switching network element, and a switching system interconnected by a switching access device. system.

11. A computer program, including program instructions, which when executed by a switching device, enable the switching device to execute the method described in any one of claims 1-5.

12. A carrier carrying the computer program of claim 11.