WO2016184069A1

WO2016184069A1 - Route lookup method and device

Info

Publication number: WO2016184069A1
Application number: PCT/CN2015/095448
Authority: WO
Inventors: 严敏; 王涛
Original assignee: 中兴通讯股份有限公司
Priority date: 2015-05-20
Filing date: 2015-11-24
Publication date: 2016-11-24
Also published as: CN106302178A; CN106302178B

Abstract

Disclosed are a route lookup method and device. The method comprises: searching, based on a pre-built two-tier tree-shaped storage structure, a first tier of the tree-shaped storage structure for a first route cluster associated with a route table entry to be queried; searching the first route cluster for a first routing apparatus associated with the route table entry to be queried; and searching the first routing apparatus for the route table entry to be queried, and returning a lookup structure, wherein the first routing apparatus is a leaf node of the first tier of the tree-shaped storage structure, and is also a root node of a second tier of the tree-shaped storage structure. The lookup structure of the route table entry to be queried can be obtained by performing the lookup three times only, thereby significantly speeding up the route lookup process.

Description

Route query method and device

Technical field

The present invention relates to the field of route optimization, and in particular, to a route query method and apparatus.

Background technique

For high-speed routers, the packet forwarding capability is at least 20Mpps and supports at least 250,000 forwarding routes. Clustering technology emerged as a single router could not continue to scale to meet demand. The cluster system can work well between the single routers of each router, which greatly expands the capacity of the router. Since the cluster router is only embodied as a router, the network topology and routing strategy become simple and clear. However, the router cluster system involves many individual devices. When the system is running at full load, while ensuring high reliability and high stability, the routing query speed between multiple routers plays a crucial role in the performance of the high-speed router.

After learning a routing entry, the switching device stores it in a software layer routing table for soft forwarding by a central processing unit (CPU), and then sends it to the forwarding chip for hardware implementation. Layer-forward hardware layer routing table. When a routing entry needs to be updated or deleted, the CPU needs to query the routing table entry from the software layer routing table, and then update or delete it. Finally, the hardware layer routing table in the forwarding chip is updated or deleted. Therefore, the query efficiency of the routing entry of the software layer directly affects the progress of the routing entry being sent to the hardware layer, which affects the progress of packet hardware layer forwarding. The query efficiency of software layer routing entries usually depends on how the routing entries are stored. The cluster system routing table storage mode has a more obvious impact on routing query efficiency.

The existing Internet Protocol (IP) route storage methods are mostly based on a tree. The public network and each virtual private network (VPN) occupy a tree and use the IP address prefix as a tree. node. For an IP address prefix with a maximum length of 32 bits, the depth of the tree is 32 layers. Then, when the IP address is used to traverse each layer in order from the root node of the tree to find the routing entry, it takes up to 32 searches to find it. The target node corresponding to the routing table entry is to be searched, so the query efficiency is low.

Summary of the invention

In order to solve the above technical problem, the present invention provides a route query method and device, which solves the problem that the route query speed is slow and the query efficiency is low in the prior art.

According to an aspect of the embodiments of the present invention, a route query method is provided, including:

According to the routing entry to be queried, in the first-level tree-shaped storage structure formed by the multiple routing devices in the single routing cluster, the root node associated with the routing entry to be queried is searched to obtain the first routing cluster; The routing cluster is a root node of the first-level tree storage structure, and the routing device is a leaf node of the first-level tree-shaped storage structure;

In a second-level tree-shaped storage structure formed by a plurality of routing entries in a single routing device, searching for a root node associated with the routing entry to be queried, to obtain a first routing device; wherein, the first-level tree The leaf node of the storage structure is the root node of the second-level tree storage structure, and the routing entry is the leaf node of the second-level tree storage structure;

Find the leaf node that is the same as the routing entry to be queried under the root node of the second-level tree storage structure, and return the query result.

Optionally, in the first-level tree-shaped storage structure formed by the multiple routing devices in the single routing cluster, the root node associated with the routing entry to be queried is obtained according to the routing entry to be queried, and the first node is obtained. The steps of routing a cluster include:

In the first-level tree-shaped storage structure, the first hash address is obtained by using the routing entry to be queried as a key and calculating according to the first preset hash function; wherein the first hash address stores The routing cluster associated with the routing entry to be queried;

The candidate routing cluster is read in the first hashing address. If the candidate routing cluster includes the routing entry to be queried, the candidate routing cluster is used as the first routing cluster.

Optionally, in the second-level tree-shaped storage structure formed by the multiple routing entries of the single routing device, the step of searching for the root node associated with the routing entry to be queried, the step of obtaining the first routing device includes:

In the second-level tree-shaped storage structure, the second hash address is obtained by using the routing entry to be queried as a key and calculating according to the second preset hash function; wherein, the second hash address stores The routing device associated with the routing entry to be queried;

The candidate routing device is read in the second hash address. If the candidate routing device includes the routing entry to be queried, the candidate routing device is used as the first routing device.

Optionally, the step of searching for the same leaf node as the routing entry to be queried under the root node of the second-level tree storage structure, and returning the query structure includes:

In the second-level tree-shaped storage structure in which the first routing device is the root node, the third hash address is obtained by using the routing entry to be queried as a key and calculating according to the third preset hash function; All routing entries of the first routing device are stored in the third hash address;

Reading the corresponding candidate routing entry in the third hash address, if the candidate routing entry is the routing table to be queried If the item is found, the search succeeds; otherwise, the linear list is traversed to find the routing entry to be queried.

Optionally, in the first-level tree-shaped storage structure formed by multiple routing devices in a single routing cluster, the root node associated with the routing entry to be queried is searched for according to the routing entry to be queried. Before the step of routing the cluster, it also includes:

Obtaining a routing entry to be queried, and determining whether the routing entry to be queried is a preset frequent entry; wherein the preset frequent entry is a routing entry whose occupation rate is higher than a preset threshold;

If not, traverse the linear linked list to find the routing entry to be queried;

If so, the first routing cluster is looked up in the first level tree storage structure.

Obtaining a frequent entry in a plurality of routing devices in a single routing cluster, and creating a first-level tree storage structure of multiple routing devices in the routing cluster corresponding to the frequent items according to the first preset hash function, and storing the routing clusters In the root node in the first level tree storage structure;

According to the second preset hash function, the second-level tree storage structure of the routing entry under the routing device corresponding to the frequent item is created, and the routing device is stored in the leaf node or the first level in the first-level tree storage structure. In the root node of the secondary tree storage structure;

According to the third preset hash function, the routing table entry is stored in the leaf node of the second level tree storage structure.

Optionally, the first-level tree-shaped storage structure of the plurality of routing devices in the routing cluster corresponding to the frequent items is created according to the first preset hash function, and the routing cluster is stored in the root of the first-level tree-shaped storage structure. The steps in the node include:

Taking the frequent item as a key, and performing calculation according to the first preset hash function, obtaining the first hash address, and storing the corresponding routing cluster in the first hash address;

A plurality of first hash addresses storing different routing clusters are constructed as root nodes of the first level tree storage structure.

Optionally, the second-level tree-shaped storage structure of the routing entry under the routing device corresponding to the frequent item is created according to the second preset hash function, and the routing device is stored in the leaf of the first-level tree-shaped storage structure. The steps in the root node of the node or the second level tree storage structure include:

Taking the frequent item as a key and performing calculation according to the second preset hash function, obtaining a second hash address, and Storing the corresponding routing device in the second hash address;

A plurality of second hash addresses storing different routing devices are constructed as a leaf node of the first level tree storage structure or a root node of the second level tree storage structure.

Optionally, the step of storing the routing entry in the leaf node of the second-level tree storage structure according to the third preset hash function includes:

Taking a routing entry as a key, and performing calculation according to the third preset hash function, obtaining a third hash address, and storing the corresponding routing entry in the third hash address;

A plurality of third hash addresses storing different routing table entries are constructed as leaf nodes of the second level tree storage structure.

Optionally, the first level tree storage structure of the plurality of routing devices in the routing cluster corresponding to the frequent items is created according to the first preset hash function, and the routing cluster is stored in the first level tree storage structure. After the steps in the root node, it also includes:

When adding a new routing cluster, obtain frequent items of the new routing cluster;

The frequent item is used as a key, and the first preset hash function is used to calculate, the first hash address is obtained, and the corresponding new routing cluster is stored in the first hash address, and the first level tree storage structure is updated. Root node.

Optionally, the first level tree storage structure of the plurality of routing devices under the routing cluster corresponding to the frequent items is created according to the first preset hash function, and the routing cluster is stored in the first level tree storage structure. After the steps in the root node, it also includes:

When the routing cluster is reduced, the routing cluster in the corresponding first hash address is deleted, and the root node of the first-level tree storage structure is updated.

Optionally, the second-level tree-shaped storage structure of the routing entry under the routing device corresponding to the frequent item is created according to the second preset hash function, and the routing device is stored in the leaf of the first-level tree-shaped storage structure. After the steps in the root node of the node or the second-level tree storage structure, the method further includes:

When adding a new routing device, acquire frequent items of the new routing device;

The frequent item is used as a key, and the second preset hash address is calculated according to the second preset hash function, and the corresponding new routing device is stored in the second new hash address to update the first level tree storage. The root node of the structure's leaf node or secondary tree storage structure.

Optionally, the second level tree storage structure of the routing entry under the routing device corresponding to the frequent item is created according to the second preset hash function, and the routing device is stored in the first level tree storage structure. Leaf node or second After the steps in the root node of the level tree storage structure, it also includes:

When the routing device is reduced, the routing device stored in the corresponding second hash address is deleted, and the root node of the leaf node of the first level tree storage structure or the root node of the secondary tree storage structure is updated.

Optionally, after the step of storing the routing entry in the leaf node of the second-level tree storage structure according to the third preset hash function, the method further includes:

When a new routing entry is added, the frequent entries of the new routing entry are obtained.

The frequent item is used as a key, and the third preset hash function is calculated according to the third preset hash function, and the corresponding new routing entry is stored in the third hash address, and the second level tree storage is updated. The structure of the leaf nodes.

When the routing entry is decreased, the routing entry stored in the corresponding third hash address is deleted, and the leaf node of the second-level tree storage structure is updated.

According to another aspect of the embodiments of the present invention, a route query apparatus is further provided, including:

The first search module is configured to search for a root node associated with the to-be-queried routing entry in a first-level tree-shaped storage structure formed by multiple routing devices in a single routing cluster according to the routing entry to be queried. Obtaining a first routing cluster; wherein the routing cluster is a root node of the first-level tree-shaped storage structure, and the routing device is a leaf node of the first-level tree-shaped storage structure;

a second search module, configured to search for a root node associated with the routing entry to be queried in a second-level tree storage structure formed by a plurality of routing entries in a single routing device, to obtain a first routing device; The leaf node of the first-level tree-shaped storage structure is a root node of the second-level tree-shaped storage structure, and the routing entry is a leaf node of the second-level tree-shaped storage structure;

The third search module is configured to search for the same leaf node as the routing entry to be queried under the root node of the second-level tree storage structure, and return the query result.

Optionally, the first search module includes:

The first search unit is configured to perform, in the first-level tree storage structure, a routing entry to be queried as a key, and perform calculation according to the first preset hash function to obtain a first hash address; wherein, the first A hash cluster is stored with a route cluster associated with the routing entry to be queried;

The first reading unit is configured to read the corresponding candidate routing cluster in the first hashing address. If the candidate routing cluster includes the routing entry to be queried, the candidate routing cluster is used as the first routing cluster.

Optionally, the second search module includes:

a second search unit is configured to perform, in the second-level tree storage structure, a routing entry to be queried as a key, and perform calculation according to the second preset hash function to obtain a second hash address; wherein, the second A routing device associated with the routing entry to be queried is stored in the hash address;

The second reading unit is configured to read the corresponding candidate routing device in the second hash address. If the candidate routing device includes the routing entry to be queried, the candidate routing device is used as the first routing device.

Optionally, the third search module includes:

The third search unit is configured to use the routing entry to be queried as a key in the second-level tree storage structure of the first routing device as the root node, and perform calculation according to the third preset hash function to obtain the first a three-hash address; wherein the third hash address stores all routing entries of the first routing device;

The third reading unit is configured to read the corresponding candidate routing entry in the third hash address, and if the candidate routing entry is the routing entry to be queried, the search succeeds; otherwise, traversing the linear linked list to find the routing table to be queried item.

Optionally, the route querying device further includes:

The determining module is configured to obtain a routing entry to be queried, and determine whether the routing entry to be queried is a preset frequent item; wherein the preset frequent item is a routing entry whose occupation rate is higher than a preset threshold;

Optionally, the route querying device further includes:

The first creating module is configured to obtain a frequent item in multiple routing devices in a single routing cluster, and create a first-level tree of multiple routing devices in the routing cluster corresponding to the frequent item according to the first preset hash function. Storing the structure and storing the routing cluster in a root node in the first level tree storage structure;

The second creating module is configured to create a second-level tree storage structure of the routing entry under the routing device corresponding to the frequent item according to the second preset hash function, and store the routing device in the first-level tree storage structure In the root node of the leaf node or the second level tree storage structure;

The third creating module is configured to store the routing entry in the leaf node of the second level tree storage structure according to the third preset hash function.

Optionally, the first creating module includes:

a first calculating unit, configured to use a frequent item as a key, and perform calculation according to the first preset hash function, Obtaining a first hash address, and storing the corresponding routing cluster in the first hash address;

The first creating unit is configured to construct a plurality of first hash addresses storing different routing clusters as root nodes of the first level tree storage structure.

Optionally, the second creating module includes:

a second calculating unit, configured to use a frequent item as a key, and perform calculation according to the second preset hash function to obtain a second hash address, and store the corresponding routing device in the second hash address;

The second creating unit is configured to construct a plurality of second hash addresses storing different routing devices as a leaf node of the first level tree storage structure or a root node of the second level tree storage structure.

Optionally, the third creating module includes:

The third calculating unit is configured to use the routing entry as a key, and perform calculation according to the third preset hash function to obtain a third hash address, and store the corresponding routing entry in the third hash address;

The third creating unit is configured to construct a plurality of third hash addresses storing different routing table entries as leaf nodes of the second level tree storage structure.

Optionally, the route querying device further includes:

The first obtaining module is configured to acquire frequent items of the new routing cluster when adding a new routing cluster;

The first update module is configured to use a frequent item as a key, and perform calculation according to the first preset hash function to obtain a first hash address, and store the corresponding new routing cluster in the first hash address, and update The root node of the first level tree storage structure.

Optionally, the route querying device further includes:

The second update module is configured to: when the routing cluster is reduced, delete the routing cluster in the corresponding first hash address, and update the root node of the first level tree storage structure.

Optionally, the route querying device further includes:

The second obtaining module is configured to acquire a frequent item of the new routing device when adding a new routing device;

The third update module is configured to use a frequent item as a key, and perform calculation according to the second preset hash function to obtain a second hash address, and store the corresponding new routing device in the second new hash address. Update the root node of the leaf node or the secondary tree storage structure of the first-level tree storage structure.

Optionally, the route querying device further includes:

The fourth update module is configured to: when the routing device is reduced, delete the routing device stored in the corresponding second hash address, and update the root node of the leaf node or the secondary tree storage structure of the first-level tree storage structure point.

Optionally, the route querying device further includes:

The third obtaining module is configured to acquire a frequent item of the new routing entry when the new routing entry is added;

The fifth update module is configured to use a frequent item as a key, and perform calculation according to the third preset hash function to obtain a third hash address, and store the corresponding new routing entry in the third hash address. Update the leaf nodes of the second level tree storage structure.

Optionally, the route querying device further includes:

The sixth update module is configured to: when the routing entry is reduced, delete the routing entry stored in the corresponding third hash address, and update the leaf node of the second-level tree storage structure.

The beneficial effects of the embodiment of the present invention are: a route query method and device, and searching for a route entry to be queried in a first-level tree storage structure based on a pre-created two-level tree storage structure The first routing cluster searches for the first routing device associated with the routing entry to be queried in the first routing cluster, and then searches for the routing entry to be queried on the first routing device, and returns a query structure, where A routing device is a leaf node in a first level tree storage structure and a root node in a second level tree storage structure. In this way, only three search processes are required, and the query structure of the routing entry to be queried can be obtained, which greatly improves the query speed of the route.

DRAWINGS

The drawings described herein are intended to provide a further understanding of the invention, and are intended to be a part of the invention. In the drawing:

1 is a schematic flow chart showing a route query method of the present invention;

Figure 2 is a schematic view showing the specific flow of the step 10 in Figure 1;

Figure 3 is a schematic view showing the specific flow of the step 20 in Figure 1;

4 is a schematic diagram showing the specific flow of step 30 in FIG. 1;

FIG. 5 is a schematic diagram showing a specific process before step 10 is performed in FIG. 1;

6 is a schematic diagram showing a process of creating a tree-shaped storage structure in an embodiment of the present invention;

Fig. 7 is a block diagram showing the structure of a route inquiring device of the present invention.

In the figure: 101, the first search module, 102, the second search module, 103, the third search module.

detailed description

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While the invention has been shown and described with reference to the embodiments Rather, these embodiments are provided so that this invention may be more fully understood and the scope of the invention can be fully conveyed by those skilled in the art.

Example

In the case of increasing network demand, the cluster concept is widely used in various network topologies. In order to expand the capacity of the router, a routing cluster is introduced. However, because there are many routing devices involved in the routing cluster, the routing query is The speed affects the overall performance. To improve the query speed, as shown in FIG. 1 , an embodiment of the present invention provides a route query method, which specifically includes the following steps:

Step 10: According to the routing entry to be queried, in the first-level tree-shaped storage structure formed by multiple routing devices in a single routing cluster, the root node associated with the routing entry to be queried is searched to obtain the first route. Cluster.

The routing cluster forms a root node of the first-level tree-shaped storage structure, and the routing device forms a leaf node of the first-level tree-shaped storage structure. When you need to query a routing entry, you need to find the routing cluster associated with it in the first-level tree storage structure.

Step 20: In the second-level tree-shaped storage structure formed by the multiple routing entries of the single routing device, the root node associated with the routing entry to be queried is searched to obtain the first routing device.

The leaf node of the first-level tree-shaped storage structure is the root node of the second-level tree-shaped storage structure, and the routing entry is the leaf node of the second-level tree-shaped storage structure; that is, the routing device is the first-level tree. The leaf node of the shape storage structure is the root node of the second level tree storage structure. That is to say, each routing cluster forms a first-level tree-shaped storage structure, and each routing device forms a second-level tree-shaped storage structure, so that after the first routing cluster is found, it can be under the first routing cluster. Finding a first routing device associated with the routing entry to be queried.

Step 30: Search for the same leaf node as the routing entry to be queried under the root node of the second-level tree storage structure, and return the query result.

Here, after the corresponding first routing device is found, the first routing device searches for the same leaf node as the routing entry to be queried, that is, whether the routing entry to be queried exists in the first routing device, and if so, The search succeeds, and if it does not exist, the search fails.

The route query method in the embodiment of the present invention is based on the pre-created two-level tree storage structure, and searches for the first route cluster associated with the to-be-queried routing entry in the first-level tree-shaped storage structure, and then in the first The routing device searches for the first routing device associated with the routing entry to be queried, and then searches for the routing entry to be queried on the first routing device, and returns a query structure, where the first routing device is a first-level tree. The leaf node in the storage structure is the root node in the second-level tree storage structure. In this way, only three search processes are required, and the query structure of the routing entry to be queried can be obtained, which greatly improves the query speed of the route.

Optionally, the hash tree can be used in the embodiment of the present invention because the structure is simple, and the search speed is fast, and the hash algorithm can be replaced conveniently, so that it is often used to store key data. The tree structure stores the routes. Step 10 can be specifically implemented by referring to the steps shown in FIG. 2:

Step 11: In the first-level tree-shaped storage structure, the first hash address is obtained by using the routing entry to be queried as a key and performing calculation according to the first preset hash function.

Here, the first hash address stores a routing cluster associated with the routing entry to be queried; when the routing entry to be queried is used as the key K, and K is substituted into the root node of the first-level tree storage structure The first preset hash function H_1 is used to calculate the first hash address H_1(K).

Step 12: The candidate routing cluster is read in the first hash address. If the candidate routing cluster includes the routing entry to be queried, the candidate routing cluster is used as the first routing cluster.

Here, the corresponding candidate routing cluster is read in the first hash address H_1(K), and it is determined whether there is a routing entry to be queried in the candidate routing cluster, and if present, the candidate routing cluster is used as the first routing cluster.

Optionally, the specific implementation manner of searching for the first routing device in step 20 is similar to the specific implementation manner of searching for the first routing cluster in step 10, and may be implemented by referring to the steps shown in FIG. 3:

Step 21: In the second-level tree-shaped storage structure, the second hash address is obtained by using the routing entry to be queried as a key and performing calculation according to the second preset hash function.

Here, the second hash address stores a routing device associated with the routing entry to be queried; the routing entry to be queried is used as the key K, and K is substituted into the leaf node that creates the first-level tree-shaped storage structure or The second preset hash function H_2 used in the root node of the second level tree storage structure calculates the second hash address H_2(K).

Step 22: The corresponding routing device is read in the second hash address. If the candidate routing device includes the routing entry to be queried, the candidate routing device is used as the first routing device.

Here, the corresponding candidate routing device is read in the second hash address H_2(K), and it is determined whether there is a routing entry to be queried in the candidate routing device, and if present, the candidate routing device is used as the first routing device.

Optionally, step 30 can be implemented by referring specifically to the steps shown in FIG. 4:

Step 31: In the second-level tree-shaped storage structure in which the first routing device is the root node, use the routing entry to be queried as a key, and perform calculation according to the third preset hash function to obtain a third hash address. .

All the routing entries of the first routing device are stored in the third hash address, and the routing entry to be queried is used as the key K, and the K is used to create the leaf node of the second-level tree storage structure. The third preset hash function H_3, calculate the third hash address H_3 (K)

Step 32: The corresponding candidate routing entry is read in the third hash address. If the candidate routing entry is the routing entry to be queried, the search succeeds; otherwise, the linear linked list is traversed to find the routing entry to be queried.

Here, the corresponding routing entry is read in the third hash address H_3(K) and compared with the routing entry to be queried. If they are equal, the search succeeds and the query structure is fed back; if not, Then, the next address is searched according to the method of processing conflicts when the tree storage structure is created, until the routing entry stored in an address is the same as the routing entry to be queried or when an address is not occupied. The search is stopped. In this embodiment, the conflicting routing entry is stored in the linear linked list. When the found routing entry is not equal to the routing entry to be queried, the linear linked list is traversed.

Optionally, for routing entries with lower frequency or lower frequency, a linear linked list storage manner may also be adopted. Preferably, we may store the frequently used items that are queried or used in a tree storage structure to improve the query speed, and For infrequent items, they are stored in a linear linked list to reduce the complexity of routing queries. Based on the above, the route search method of the embodiment of the present invention, as shown in FIG. 5, before step 10, may further include:

Step 01: Obtain a routing entry to be queried, and determine whether the routing entry to be queried is a preset frequent entry.

The preset frequent item is a routing entry whose occupation rate is higher than a preset threshold. For example, we can set the preset threshold to 0.001, so that when the entire routing system includes 100,000 routing entries, the routing entry A If the number of occurrences is greater than or equal to 100, the routing entry A is a frequent entry.

Step 02: If not, traverse the linear linked list to find the routing entry to be queried; if yes, look up the first routing cluster in the first-level tree storage structure.

Optionally, before step 10, the step of creating a tree storage structure as shown in FIG. 6 is further included.

Step 0A: Acquire frequent items in multiple routing devices in a single routing cluster, and create a first-level tree storage structure of multiple routing devices in the routing cluster corresponding to the frequent items according to the first preset hash function, and The routing cluster is stored in the root node in the first level tree storage structure.

Optionally, step 0A can be specifically implemented by referring to the following steps:

The frequent item is used as a key, and the calculation is performed according to the first preset hash function to obtain a first hash address, and the corresponding routing cluster is stored in the first hash address. Here, the first preset hash function is H_1, and each frequent item K_i is substituted into the first preset hash function H_1 to obtain a first hash address H_1(K_i), and the routing cluster including the frequent item K_i is obtained. Stored in the first hash address H_1 (K_i).

Step 0B: Create a second-level tree-shaped storage structure of the routing entry under the routing device corresponding to the frequent item according to the second preset hash function, and store the routing device in the leaf node in the first-level tree-shaped storage structure. Point or the root node of the second level tree storage structure.

Optionally, step 0B can be specifically implemented by referring to the following steps:

Taking the frequent item as a key and performing calculation according to the second preset hash function, the second hash address is obtained, and the corresponding routing device is stored in the second hash address. Here, the second preset hash function is H_2, and each frequent item K_i is substituted into the second preset hash function H_2 to obtain a second hash address H_2(K_i), and the routing cluster including the frequent item K_i is obtained. Stored in the second hash address H_2(K_i).

Step 0C: Store the routing entry in the leaf node of the second-level tree storage structure according to the third preset hash function.

Optionally, step 0C can be specifically implemented by referring to the following steps:

The routing table entry is used as a key, and is calculated according to the third preset hash function to obtain a third hash address, and the corresponding routing entry is stored in the third hash address. Here, the third preset hash function is H_3, and each frequent item K_i is substituted into the third preset hash function H_3 to obtain a third hash address H_3 (K_i), and the routing cluster including the frequent item K_i is obtained. Stored in the third hash address H_3 (K_i).

In other words, the routing entries of a single routing device are stored in a tree structure. The routing entry is used as the leaf node of the tree structure. If a routing entry is found on a routing device, In the case of K, the third preset hash function H_3, which is used when the K is built into the tree, is used to calculate the third hash address H_3(K), and the routing entry stored in the address is read, and the routing entry to be queried is read. K is compared. If they are equal, the query is successful. Otherwise, the linear list is traversed until the search fails or the search is successful.

The above-mentioned routing devices are divided into multiple routing clusters, and the support degree of each routing entry in each routing cluster is counted and calculated in parallel, and frequent items with a support degree higher than a preset threshold are obtained, and frequent items are supported. Sorting the descending order of the degree, sorting the routing devices according to the sorted frequent items list, and then calculating the second hash address according to the routing table entry K and according to the second preset hash function H_2 in the divided group. The corresponding routing device is stored in the second hash address, that is, a complete tree storage structure is formed in each of the individual routing clusters.

The routing cluster is regarded as a whole, and a plurality of different routing clusters are stored in different first hash addresses by using a preset first hash function H_1.

Optionally, after the tree storage structure is built, when frequent items, routing devices, or routing clusters change, the tree storage structure changes, which involves updating the tree storage structure. This section describes how to update the tree storage structure when frequent items, routing devices, or routing clusters change.

Case 1: When the frequent items change, the data stored in the first hash address, the second hash address, and the third hash address in the old frequent item mapping relationship is deleted, and the first hash under the new frequent item mapping relationship is added. Data stored in the hash address, the second hash address, and the third hash address to implement updating of data in the tree storage structure. Specifically, refer to the following steps:

1) Calculate 〖L〗_Δ1=〖L〗_1'-L_1, where 〖L〗_1' is the item set of the frequent item routing entry 1 of the original routing cluster under the new frequent item, and L_1 is the original threshold under the original cluster Frequent 1-item set of device routing;

2) Determine whether the difference 〖L〗_Δ1 is an empty set, if yes, go to step 04), otherwise go to step 03):

3) updating the first level tree storage structure by the difference 〖L〗_Δ1;

4) The first-level tree storage structure is updated to be the same as the original first-level tree storage structure.

Step 3 can be specifically referred to as follows:

01) Judging whether the difference set 〖L〗_Δ1 is an empty set, and then ending the process;

02) Update frequent item list L_1'=L_1∪〖L〗_Δ1;

03) Sorting the updated frequent item list L_1' in descending order;

04) Execute nItem=L_1'∩t for any item t in the original cluster device route set, and take out the routing entry that intersects the frequent item list in the routing entry to be queried;

05) Execute nNode=nItem∩〖L〗_Δ1, and the routing entry to be queried in the route set appearing in the frequent list intersects the difference set 〖L〗_Δ1 to find a new nNode;

06) Insert the new nNode into the address corresponding to the tree storage structure, and the update ends.

Case 2: When a new route cluster is added to cause frequent item changes, the frequent items of the new route cluster are obtained, and the frequent items are used as keywords, and the first preset hash function is used to calculate, and the first hash address is obtained. And storing the corresponding new routing cluster in the first hash address, and updating the root node of the first level tree storage structure. First, calculate [L]_Δ2=L_█(DP1@)+L_dP1-L_1, where L_DP1 is the item set of routing entry 1 in the original routing cluster under the new frequent item, and L_DP1 is the new route under the new frequent item. The item set of the routing entry 1 of the cluster, L_1 is the item set of the routing entry 1 of the original routing cluster under the original frequent item; and then the routing cluster stored in the first hashing address is updated by the difference [L]_Δ2.

Here, the new route cluster may cause frequent items to change. Therefore, you need to obtain frequent items again. For details about the frequent items, refer to the following:

11) Initialize k=1;

12) Let k=k+1, using the Apriori algorithm, by adding the item set L_DP1 of the frequent item routing entry 1 of the routing cluster, where l=k-1, generating a candidate frequent item routing entry k of the newly added routing set The item set c_dk determines whether the item set c_dk of the candidate frequent item routing table entry k of the newly added route set is an empty set, and the mining ends;

13) Execute c_Δk=c_dk-L_k, find the difference between the item set c_dk of the candidate frequent item routing entry k of the newly added routing set and the item set L_k of the original routing cluster frequent item routing entry k under the original frequent item, and judge the difference Whether the value c_Δk is an empty set, if yes, perform step 15), otherwise perform step 14);

14) For each of the difference c_Δk obtained in the step 3), the support number of each path is calculated by the updated tree storage structure; by determining whether the support number of the item in c_Δk is not less than the new threshold s', Get the item set of the new frequent item routing entry k.

15) By determining whether the supported number of items in c_dk is not less than the new threshold s', the item set L_dP1 of the frequent item routing entry k of the newly added routing cluster is obtained.

Case 3: When the routing cluster is reduced, the routing cluster in the corresponding first hash address is deleted, and the root node of the first-level tree storage structure is updated.

Case 4: When adding a new routing device, obtain frequent items of the new routing device;

The frequent item is used as a key, and the second preset hash address is calculated according to the second preset hash function, and the corresponding new routing device is stored in the second new hash address to update the first level tree storage. The root node of the structure's leaf node or secondary tree storage structure. The specific implementation is similar to the implementation of Case 2, and therefore will not be described here.

Case 5: When the routing device is reduced, the routing device stored in the corresponding second hash address is deleted, and the leaf node of the first level tree storage structure or the root node of the secondary tree storage structure is updated.

Case 6: When a new routing entry is added, a frequent entry of a new routing entry is obtained;

Case 7: When the routing entry is reduced, the routing entry stored in the corresponding third hash address is deleted, and the leaf node of the second-level tree storage structure is updated.

According to another aspect of the embodiments of the present invention, a route query device, as shown in FIG. 7, includes:

The first search module 101 is configured to search for a root node associated with the routing entry to be queried in the first-level tree storage structure formed by multiple routing devices in a single routing cluster according to the routing entry to be queried. Obtaining a first routing cluster; wherein the routing cluster is a root node of the first-level tree-shaped storage structure, and the routing device is a leaf node of the first-level tree-shaped storage structure;

The second search module 102 is configured to search for a root node associated with the routing entry to be queried in the second-level tree storage structure formed by the multiple routing entries of the single routing device, to obtain the first routing device. Wherein, the leaf node of the first level tree storage structure is the root node of the second level tree storage structure, and the routing table entry is the leaf node of the second level tree storage structure;

The third search module 103 is configured to search for the same leaf node as the routing entry to be queried under the root node of the second-level tree storage structure, and return the query result.

Optionally, the first searching module 101 includes:

Optionally, the second search module 102 includes:

Optionally, the third lookup module 103 includes:

Optionally, the route querying device further includes:

Optionally, the first creating module includes:

The first calculating unit is configured to use a frequent item as a key, and perform calculation according to the first preset hash function to obtain a first hash address, and store the corresponding routing cluster in the first hash address;

Optionally, the second creating module includes:

Optionally, the third creating module includes:

Optionally, the route querying device further includes:

It should be noted that the route querying device is a device corresponding to the above-mentioned route query method, and all the implementation manners in the foregoing method embodiments are suitable for the embodiment of the device, and the same technical effects can be achieved.

The above is a preferred embodiment of the present invention, and it should be noted that those skilled in the art can also make several improvements and retouchings without departing from the principles of the present invention. Within the scope of protection of the invention.

Industrial applicability

The technical solution provided by the embodiment of the present invention is applied to a route query process, and a pre-created two-level tree storage structure is used in the process, and the first-level tree-shaped storage structure is searched for related to the to-be-queried routing entry. The first routing cluster is connected to the first routing device, and then the first routing device associated with the routing entry to be queried is searched for, and then the routing entry to be queried is searched for by the first routing device, and the query structure is returned. The first routing device is a leaf node in the first level tree storage structure and a root node in the second level tree storage structure. In this way, only three search processes are required, and the query structure of the routing entry to be queried can be obtained, which greatly improves the query speed of the route.

Claims

A route query method includes:

According to the routing entry to be queried, in the first-level tree-shaped storage structure formed by the multiple routing devices in the single routing cluster, the root node associated with the routing entry to be queried is searched to obtain the first routing cluster. Wherein the routing cluster is a root node of the first level tree storage structure, and the routing device is a leaf node of the first level tree storage structure;

In a second-level tree-shaped storage structure formed by a plurality of routing entries in a single routing device, searching for a root node associated with the routing entry to be queried, to obtain a first routing device; The leaf node of the first level tree storage structure is a root node of the second level tree storage structure, and the routing table entry is a leaf node of the second level tree storage structure;

Searching for the same leaf node as the routing entry to be queried under the root node of the second-level tree storage structure, and returning the query result.
The route query method according to claim 1, wherein the searching and the to-be-queried are performed in a first-level tree-shaped storage structure formed by a plurality of routing devices under a single routing cluster according to the routing entry to be queried The root node associated with the routing entry, the steps of obtaining the first routing cluster include:

In the first-level tree-shaped storage structure, the first hash address is obtained by using the to-be-queried routing entry as a key and calculating according to the first preset hash function; wherein, the first hash A routing cluster associated with the to-be-queried routing entry is stored in the hash address;

The candidate routing cluster is read in the first hashing address. If the candidate routing cluster includes the to-be-queried routing entry, the candidate routing cluster is used as the first routing cluster.
The route query method according to claim 1, wherein in the second-level tree storage structure formed by the plurality of routing entries under the single routing device, the root node associated with the routing entry to be queried is searched for Point, the steps of obtaining the first routing device include:

In the second-level tree-shaped storage structure, the second hash address is obtained by using the to-be-queried routing entry as a key and calculating according to the second preset hash function; wherein the second hash is obtained. A routing device associated with the to-be-queried routing entry is stored in the hash address;

The candidate routing device is read in the second hash address. If the candidate routing device includes the to-be-queried routing entry, the candidate routing device is used as the first routing device.
The route query method according to claim 1, wherein the step of searching for the same leaf node as the to-be-queried routing entry under the root node of the second-level tree storage structure, and returning the query structure includes :

In the second-level tree-shaped storage structure in which the first routing device is a root node, using the to-be-queried routing entry as a key, and performing calculation according to the third preset hash function, obtaining a third hash. An address; wherein all the routing entries of the first routing device are stored in the third hash address;

Reading the corresponding candidate routing entry in the third hash address, if the candidate routing entry is the to-be-queried routing entry, the search succeeds; otherwise, traversing the linear linked list to find the to-be-queried routing table item.
The route query method according to claim 1, wherein in the first-level tree-shaped storage structure formed by a plurality of routing devices under a single routing cluster, the route to be queried is searched for according to the routing entry to be queried. Before the step of the first routing cluster is obtained, the root node associated with the entry includes:

Obtaining a routing entry to be queried, and determining whether the routing entry to be queried is a preset frequent entry; wherein the preset frequent entry is a routing entry whose occupation rate is higher than a preset threshold;

If not, traversing the linear linked list to find the routing entry to be queried;

If yes, the first routing cluster is looked up in the first level tree storage structure.
The route query method according to any one of claims 1 to 5, wherein, in the first-level tree-shaped storage structure formed by a plurality of routing devices under a single routing cluster according to the routing entry to be queried, searching and Before the step of obtaining the first routing cluster, the root node associated with the routing entry to be queried includes:

Obtaining a frequent entry in a plurality of routing devices in a single routing cluster, and creating a first-level tree storage structure of the plurality of routing devices in the routing cluster corresponding to the frequent items according to the first preset hash function, and The routing cluster is stored in a root node in the first level tree storage structure;

Generating, according to the second preset hash function, a second level tree storage structure of the routing entry under the routing device corresponding to the frequent item, and storing the routing device in the first level tree storage structure a leaf node or a root node of the second level tree storage structure;

And storing, according to the third preset hash function, the routing table entry in a leaf node of the second level tree storage structure.
The route query method according to claim 6, wherein the first level tree storage structure of the plurality of routing devices in the routing cluster corresponding to the frequent item is created according to the first preset hash function, and the route is The steps of storing the cluster in a root node in the first level tree storage structure include:

Taking the frequent item as a key, and performing calculation according to the first preset hash function, obtaining a first hash address, and storing the corresponding routing cluster in the first hash address;

Storing multiple first hash addresses of different routing clusters, constructing the root of the first-level tree storage structure Node.
The route query method according to claim 6, wherein the second level tree storage structure of the routing entry under the routing device corresponding to the frequent item is created according to the second preset hash function, and the route is The step of storing the device in a leaf node in the first level tree storage structure or a root node in the second level tree storage structure includes:

Taking the frequent item as a key, and performing calculation according to the second preset hash function, obtaining a second hash address, and storing the corresponding routing device in the second hash address;

A plurality of second hash addresses storing different routing devices are constructed as a leaf node of the first level tree storage structure or a root node of the second level tree storage structure.
The route query method according to claim 6, wherein the storing the routing entry in the leaf node of the second-level tree storage structure according to the third preset hash function comprises:

Taking a routing entry as a key, and performing calculation according to the third preset hash function, obtaining a third hash address, and storing the corresponding routing entry in the third hash address;

A plurality of third hash addresses storing different routing table entries are constructed as leaf nodes of the second level tree storage structure.
The route query method according to claim 7, wherein the first level tree storage structure of the plurality of routing devices under the routing cluster corresponding to the frequent item is created according to the first preset hash function, and the After the step of storing the routing cluster in the root node in the first level tree storage structure, the method further includes:

Obtaining frequent items of the new routing cluster when adding a new routing cluster;

Taking the frequent item as a key, and performing calculation according to the first preset hash function, obtaining a first hash address, and storing the corresponding new routing cluster in the first hash address, updating the first The root node of the primary tree storage structure.
The route query method according to claim 7, wherein the first level tree storage structure of the plurality of routing devices under the routing cluster corresponding to the frequent items is created according to the first preset hash function, and the After the step of storing the routing cluster in the root node in the first-level tree storage structure, the method further includes:

When the routing cluster is reduced, the routing cluster in the corresponding first hash address is deleted, and the root node of the first-level tree storage structure is updated.
The route query method according to claim 8, wherein the second level tree storage structure of the routing entry under the routing device corresponding to the frequent item is created according to the second preset hash function, and the route is Equipment After the step of storing the leaf node in the first level tree storage structure or the root node of the second level tree storage structure, the method further includes:

Obtaining frequent items of the new routing device when adding a new routing device;

Taking the frequent item as a key, and performing calculation according to the second preset hash function, obtaining a second hash address, and storing the corresponding new routing device in the second new hash address, updating the The leaf node of the first level tree storage structure or the root node of the secondary tree storage structure.
The route query method according to claim 8, wherein the second level tree storage structure of the routing entry under the routing device corresponding to the frequent item is created according to the second preset hash function, and the After the step of storing the routing device in the leaf node in the first level tree storage structure or the root node in the second level tree storage structure, the method further includes:

When the routing device is reduced, the routing device stored in the corresponding second hash address is deleted, and the leaf node of the first level tree storage structure or the root node of the secondary tree storage structure is updated.
The route query method according to claim 9, wherein after the step of storing the routing entry in the leaf node of the second-level tree storage structure according to the third preset hash function, the method further includes :

When a new routing entry is added, the frequent entry of the new routing entry is obtained.

Taking the frequent item as a key, and performing calculation according to the third preset hash function, obtaining a third hash address, and storing the corresponding new routing entry in the third hash address, updating the The leaf node of the second level tree storage structure.
The route query method according to claim 9, wherein after the step of storing the routing entry in the leaf node of the second-level tree storage structure according to the third preset hash function, include:

When the routing entry is reduced, the routing entry stored in the corresponding third hash address is deleted, and the leaf node of the second-level tree storage structure is updated.
A route query device includes:

The first search module is configured to search for a root node associated with the to-be-queried routing entry in a first-level tree storage structure formed by multiple routing devices in a single routing cluster according to the routing entry to be queried. Pointing, obtaining a first routing cluster; wherein the routing cluster is a root node of the first level tree storage structure, and the routing device is a leaf node of the first level tree storage structure;

a second search module, configured to search for a root node associated with the to-be-queried routing entry in a second-level tree storage structure formed by a plurality of routing entries under a single routing device, to obtain a first route Equipment The leaf node of the first level tree storage structure is a root node of the second level tree storage structure, and the routing entry is a leaf node of the second level tree storage structure;

The third search module is configured to search for a leaf node that is the same as the to-be-queried routing entry under the root node of the second-level tree storage structure, and return a query result.
The route querying device according to claim 16, wherein the first lookup module comprises:

a first search unit, configured to: in the first-level tree-shaped storage structure, use the to-be-queried routing entry as a key, and perform calculation according to the first preset hash function to obtain a first hash address; The first hash address stores a routing cluster associated with the to-be-queried routing entry.

The first reading unit is configured to read the corresponding candidate routing cluster in the first hash address, and if the candidate routing cluster includes the to-be-queried routing entry, the candidate routing cluster is used as the first A routing cluster.

The route query device of claim 16, wherein the second lookup module comprises:

a second search unit, configured to: in the second-level tree storage structure, use the to-be-queried routing entry as a key, and perform calculation according to the second preset hash function to obtain a second hash address; The routing device associated with the to-be-queried routing entry is stored in the second hash address;

The second reading unit is configured to read the corresponding candidate routing device in the second hash address, and if the candidate routing device includes the to-be-queried routing entry, the candidate routing device is used as the first A routing device.

The route querying device according to claim 16, wherein the third lookup module comprises:

a third search unit, configured to use the to-be-queried routing entry as a key in the second-level tree storage structure of the first routing device as a root node, and according to a third preset hash function Calculating, obtaining a third hash address, wherein all routing entries of the first routing device are stored in the third hash address;

The third reading unit is configured to read the corresponding candidate routing entry in the third hash address, and if the candidate routing entry is the to-be-queried routing entry, the search succeeds; otherwise, the traversal is linear The linked list searches for the routing entry to be queried.
The route query device of claim 16, further comprising:

The determining module is configured to obtain a routing entry to be queried, and determine whether the routing entry to be queried is a preset frequent item; wherein the preset frequent item is a routing entry whose occupation rate is higher than a preset threshold;

If not, traversing the linear linked list to find the routing entry to be queried;

If yes, the first routing cluster is looked up in the first level tree storage structure.
The route query device according to any one of claims 16 to 20, further comprising:

The first creating module is configured to obtain a frequent item in multiple routing devices in a single routing cluster, and create a first level tree of multiple routing devices in the routing cluster corresponding to the frequent item according to the first preset hash function. Forming a storage structure, and storing the routing cluster in a root node in the first level tree storage structure;

a second creation module, configured to create a second-level tree storage structure of the routing entry under the routing device corresponding to the frequent item according to the second preset hash function, and store the routing device in the first a leaf node in the primary tree storage structure or a root node of the second level tree storage structure;

The third creating module is configured to store the routing table entry in a leaf node of the second level tree storage structure according to a third preset hash function.
The route query device according to claim 21, wherein the first creation module comprises:

a first calculating unit, configured to use the frequent item as a key, and perform calculation according to the first preset hash function to obtain a first hash address, and store the corresponding routing cluster in the first hash address in;

The first creating unit is configured to construct a plurality of first hash addresses storing different routing clusters as root nodes of the first level tree storage structure.
The route query device of claim 21, wherein the second creation module comprises:

a second calculating unit, configured to use the frequent item as a key, and perform calculation according to the second preset hash function to obtain a second hash address, and store the corresponding routing device in the second hash address in;

The second creating unit is configured to construct a plurality of second hash addresses storing different routing devices as a leaf node of the first level tree storage structure or a root node of the second level tree storage structure.
The route query device according to claim 21, wherein the third creation module comprises:

The third calculating unit is configured to use the routing entry as a key, and perform calculation according to the third preset hash function to obtain a third hash address, and store the corresponding routing entry in the third hash address. in;

The third creating unit is configured to construct a plurality of third hash addresses storing different routing table entries as leaf nodes of the second level tree storage structure.
The route query device of claim 22, further comprising:

The first obtaining module is configured to acquire a frequent item of the new routing cluster when adding a new routing cluster;

The first update module is configured to use the frequent item as a key, and perform calculation according to the first preset hash function to obtain a first hash address, and store the corresponding new routing cluster in the first hash. In the address, the root node of the first level tree storage structure is updated.
The route query device of claim 22, further comprising:

The second update module is configured to: when the routing cluster is reduced, delete the routing cluster in the corresponding first hash address, and update the root node of the first-level tree storage structure.
The route query device of claim 23, further comprising:

a second obtaining module, configured to acquire a frequent item of the new routing device when adding a new routing device;

The third update module is configured to use the frequent item as a key, and perform calculation according to the second preset hash function to obtain a second hash address, and store the corresponding new routing device in the second new In the hash address, the leaf node of the first level tree storage structure or the root node of the secondary tree storage structure is updated.
The route query device of claim 23, further comprising:

a fourth update module, configured to: when the routing device is reduced, delete the routing device stored in the corresponding second hash address, and update the leaf node or the secondary tree storage of the first level tree storage structure The root node of the structure.
The route query device according to claim 24, further comprising:

The third obtaining module is configured to acquire a frequent item of the new routing entry when adding a new routing entry;

The fifth update module is configured to use the frequent item as a key, and perform calculation according to the third preset hash function to obtain a third hash address, and store the corresponding new routing entry in the third In the hash address, the leaf node of the second level tree storage structure is updated.
The route query device according to claim 24, further comprising:

The sixth update module is configured to: when the routing entry is reduced, delete the routing entry stored in the corresponding third hash address, and update the leaf node of the second-level tree storage structure.