Initially, we will need to understand router and its function

A router :  is a device which has multiple interfaces and is connected to multiple networks

through these interfaces. This means that it can forward data from one network to another.

Router function : the router listen on all connected interfaces for incoming ip packets . When packests come in ,it takes the destination ip address and looks up this address in a routing table .

Route table function : specifies the next hop to forward this packet this packet to .This happens at every router, until the packet reaches its final destination .

The routing tables two most important information items are:

1- final destination may be one of this

The final destination is on a local network. In this case, the local interface is

specified.

The final destination is not on a local network. In this case, another router is

specified. This router normally is a system on the local network.

2- we can specify the final destination with three methods

host name : that is mean that the entry in the routing table only applies to packets sent to this specific IP address .

network route : in this method ,the entry in the routing table applies to all packets sent to any IP address which belongs in this network .

default route : in this method , the entry in the routing table applies to all packets which were not matched elsewhere in the routing table.

an example

[code]

– Host route: 129.33.151.7/255.255.255.255

– Network route: 129.33.151.0/255.255.255.0

– Default route: 0.0.0.0/0.0.0.0

[/code]

-we can see that throw terminal . – application…accessories…terminal – and make

# route