Routing Table

The routing table, refers to a router or other Internet network equipment storage watch, this table are to a specific network terminal of the path, and, in some cases, and some of these paths and related measure.

introduction

In computer networks, the routing table or says routing choose domain information database (RIB) is a storage in a router or networking computer in the electronic form (files) or kind of database. The routing table a point to specific storage network address path (in some cases, the path of record routing metrics). The routing table contains network topology information of surrounding. Routing tables set up in order to realize the main target is routing protocols and static routing.

In the modern routers of structure, the routing table not directly involved in the transmission of data packets, but used to generate a small point to list, this point to table contains only by routing algorithm of choice data packets priority path, this form is usually in order to optimize the hardware store and search and be compressed or compiled in advance. This article will ignore the implementation details and select the entire route choice/transmission information as to illustrate the routing table subsystem.

The main work

The router the main work is for the router each packet transmission path for an optimal and put the data sent to the effective purpose site. This shows, choose the best path strategy that is routing algorithm is the key to router. In order to complete the work, in the router keeps all the relevant data transmission path-routing table, for routing table when use, the information contained in the data forwarding decision of strategy. For example, the routing table like we usually use maps, the logo of the same route, the routing table kept the sign of information, online subnet router's number and the next router name, etc. Routing table can be fixed by the system administrator set good, by the system dynamic modification, the router, can also be automatic adjustment by the host controller.

1. Static routing table

In advance by the system administrator set fixed routing table called static routing table, be in commonly system installation and configuration of the network is according to the predetermined, it won't with the future of the network structure changed.

2. Dynamic routing table

Dynamic routing table is according to the operation of the system network router and automatically adjust the route table. Routers routing protocols that provide according to the function of automatic learning and memory, network movement situation, when there is a need for automatic calculation of data transmission of the best path.

The router often depend on the establishment and the maintenance of the routing table to decide how to forwarding. Routing table ability is the from the table contain within the limit of the quantity of the routing table. Because the Internet on execution BGP agreement usually have hundreds of thousands of router article, so the routing table of project also is the important embodiment of router ability.

Routing table items as follows:

First of all, the routing table every item of the purpose of network prefix. Contains field goal Second, every item and an additional fields, and is used to specify the network prefix digits subnet mask (servers). After the third, then jump field represents a router, a jump of field use routing the IP address of the value.

Understanding the Internet is available on the network address (or network ID) help routing decisions. This knowledge is called the routing tables from database available. Routing table is a series called routing, which contains information about a of the Internet network ID location information. The routing table of the router is not special. Host (the router) may also be used to determine the optimal route routing table.