Route table space managing method, apparatus, switch and router

Abstract

The invention relates to a method, a device, a switch and a router for space management of a routing table. Distribution management to the space of the routing table is carried out by the space management unit in a space management link table so as to lead the entries of layer 3 switches or routers inserted in the routing table to be arranged by the mask (prefix) length in a long-to-short order, ensure that the routing entry with the longest prefix can be matched with the one with the longest mask from the start of the matching, avoid repetitive depositing of the same entry in the routing table and the problem that the routing entry with the largest mask length can not be obtained until all entries in the routing table are matched and greatly increase the search speed of the routing table; besides, arrangement of entries in the routing table by a certain order facilitates fast insertion and deletion of the entries, the space utilization rate of the routing table is significantly improved.

Description

technical field [0001] The invention relates to data communication technology, in particular to a method and device for space management of a routing table capable of improving the routing table search speed. Background technique [0002] At present, when a certain host on the Internet accesses another host, a router or a layer-3 switch searches a routing table according to the destination Internet Protocol (Internet Protocol, IP) address, and routes to the destination host. A routing table is a table stored on a router or other Internet network equipment (layer 3 switch). In other words, a routing table is a continuous space for storing routing information, and each piece of routing information is called a routing table entry. This table stores the paths to specific network terminals. [0003] In the prior art, when an entry needs to be written into the routing table, which piece of space is allocated to it and which location in the routing table is written is determined b...

AI Technical Summary

Problems solved by technology

[0008] Since the mask length of each entry in the routing table has nothing to do with the order of the entries in the routing table, when a router or Layer 3 switch searches for a matching entry, it must either match all the entries in all the routing tables, and finally determine The entries with the longest mask length and matching result in routing table lookup efficiency are limited and cannot be further improved; or the entries in the routing table are managed in tree form, although the tree management mode makes routers or Layer 3 switches only match among them One branch can get the search result, but the routing table using the tree management method often has the problem of repeatedly storing the same table item, which leads to the insufficient and reasonable utilization of the routing table

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