3com WX3000 Manuel D’Utilisation

 

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Go to these sections for information you are interested in: 

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Routing Protocol Overview 

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Displaying and Maintaining a Routing Table 

 

The term router in this chapter refers to a router in a generic sense or a WX3000 series device running 

a routing protocol. 

 

Routers are used for route selection on the Internet. As a router receives a packet, it selects an 

appropriate route (through a network) according to the destination address of the packet and forwards 

the packet to the next router. The last router on the route is responsible for delivering the packet to the 

destination host. 

The key for a router to forward packets is the routing table. Each router maintains a routing table. Each 

entry in this table contains an IP address that represents a host/subnet and specifies which physical 

port on the router should be used to forward the packets destined for the host/subnet. And the router 

forwards those packets through this port to the next router or directly to the destination host if the host is 

on a network directly connected to the router. 

Routes in a routing table can be divided into three categories by origin: 

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Direct routes: Routes discovered by data link protocols, also known as interface routes. 

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Static routes: Routes that are manually configured. 

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Dynamic routes: Routes that are discovered dynamically by routing protocols. 

Each routing entry in a routing table contains: 

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Destination: It identifies the address of the destination host or network of an IP packet. 

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Mask: Along with the destination address, it identifies the address of the network segment where 

the destination host or router resides. By performing a logical AND operation between destination 

address and network mask, you can get the address of the network segment where the destination