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Static Routing

A static route includes the network address and subnet mask of the remote network, along with the IP address of the next-hop router or exit interface. Static routes are denoted with the code S in the routing table as shown in the figure. Static routes are examined in detail in the next chapter.

When to Use Static Routes :
Static routes should be used in the following cases:
- A network consists of only a few routers. Using a dynamic routing protocol in such a case does not present any substantial benefit. On the contrary, dynamic routing may add more administrative overhead.
- A network is connected to the Internet only through a single ISP. There is no need to use a dynamic routing protocol across this link because the ISP represents the only exit point to the Internet.
- A large network is configured in a hub-and-spoke topology. A hub-and-spoke topology consists of a central location (the hub) and multiple branch locations (spokes), with each spoke having only one connection to the hub. Using dynamic routing would be unnecessary because each branch has only one path to a given destination-through the central location.

Set Static Routing Protokols
On the routers, enter global configuration mode and configure the basic global configuration commands including:
-hostname
- enable secret
Example :
-R1(config)#interface fastethernet 0/0
-R1(config-if)#ip address 172.16.3.1 255.255.255.0
-R1(config-if)#no shutdown
Configure the IP address as specified in the Topology Diagram.
- R1(config-if)#ip address 172.16.3.1 255.255.255.0

To configure static routes with a next-hop specified, use the following syntax:
- Router(config)# ip route network-address subnet-mask ip-address
- network-address:—Destination network address of the remote network to be added to the
routing table.
- subnet-mask—Subnet mask of the remote network to be added to the routing table. The subnet mask can be modified to summarize a group of networks.
- ip-address—Commonly referred to as the next-hop router’s IP address.
- R3(config)#ip route 172.16.1.0 255.255.255.0 192.168.1.2