Router Functions
Routers will know how the network is set up and will send packets to the right place by choosing the best way through that set up.
Networks that are connected are part of dynamic information, and the router can add them to the routing table. This is dynamic because if the interface that is directly attached goes down, the router will remove things so that that destination is not in the routing table. Destinations learned through routing protocols are also part of dynamic information. Static routing can also be used in scenarios that only have one way to join to the network or the Internet, such as stub networks or places with only one link.
Finding Out What Static and Dynamic Routes Are
There is no need to worry about routing protocols, advertisements, or additional router intelligence while using static routes. They are easy to set up and provide a lot of leeway as long as you don’t go over a specific restriction for the amount of static routes. But because they are static, static routing prevents the router from responding to changes in the network.
You will be able to modify the network changes with dynamic routing protocols, but you will incur the overhead of learning networks and advertisements. The routing protocol dictates the rate of adjustment and convergence to learning or alternative path selection.
Static Routes
The implementation of static routing is an appropriate solution for situations involving stub networks, such as the one depicted in the image, which only have a single link connecting to the rest of the network.
As a unique kind of static route, upstream traffic departing the stub network usually uses the default route to send all data to any destination outside the stub network. An excellent illustration of this is the Internet. You probably don’t want to know the exact locations you’re aiming at. You are aware that every single one of them is located outside and may be accessed through that one link.
This means that, in this case, the default entry stating “any unknown destination, send it this way through router A” will suffice. The bidirectional nature of traffic should be considered whenever static routing is configured; that is, when traffic is sent out, there will be return traffic arriving. It seems like router A has to have static routing configured to point to the networks on the stub as well. It is possible to observe a combination of static and dynamic routing in certain cases. You can set up a default route at router B for outgoing traffic, and then set it up so that router A knows about those routes using the dynamic routing protocol, so that A can forward them.
Configuring Static Routes
This is the command that should be used in Cisco IOS routers in order to configure static routing.
Router(config)#ip route [network/host] [mask] [address/interface] [distance] [permanent]
You can add Classless Inter-Domain Routing Entries that point to subnets with different mask sizes because the IP route command includes both the destination network and a mask. The best entry would be a /32, which is a host entry in the routing table. A host entry means that the destination is a real host, not a network. Next-hop could be an IP address of the next router in the path or a local interface, which is the interface to use to get to the destination network.
The administrative distance for static routes is set to one by default, but this can be changed to make floating static routes for backup connection. Do not forget that the administrative distance is the protocol’s most important factor. Static routes take over most dynamic routing protocol when the admin distance is 1. A static route will win if the same destination is already known through routing protocol and a static route is inserted to it. This is because the static route has less administrative distance.
Case Study of a Static Route
This is an illustration of a static route that has been set up at router A.
