static and dynamic routing cisco

The procedure for transferring data between different networks is called routing. It is the foundation of every data network. The routers are responsible for transferring data from one network to another network. It is learning about remote networks using two ways:

• Static Routing—The network administrator manually adds remote networks to the routing table to reach a specific network. The static routing protocol cannot be updated dynamically.
• Dynamic Routing Protocols -Remote routes are automatically learned using a dynamic protocol. The route uses a dynamic routing protocol that automatically updates its table when changes occur in the network. It does not need any configuration in case of changes in the network topology.

Routers can also use both static and dynamic routing protocol methods simultaneously. Static routes do not require the same processing and overhead as dynamic routing protocols.

Static routing is possible for smaller networks with only one path to an outside network. However, static routing is too difficult with a large network, so we can easily use a dynamic routing protocol.

Most networks use a combination of dynamic routing protocols and static routes for better results and multiple paths to a destination network via static routes and dynamically learned routes.

But, a static route’s administrative distance (AD) is 1. So, a static route will take priority over all dynamically learned routes. Following are the key advantages and disadvantages of both routing types.

Advantages of Static Routing

• Static routes do not advertise their routing table over the network, resulting in better security.
• Using static routes requires less bandwidth than dynamic routing protocols, and no CPU cycles are used to calculate and communicate routes.
• The static route sends data to a known path.

Disadvantages of Static Routing

• Configuration and maintenance need more time and ability.
• When a change occurs in the network topology, it must be reconfigured manually.
• There is a higher chance of the wrong configuration in large networks.
• Requires whole network knowledge for proper implementation.
• The complexity increased with the growth of the network. So, maintenance becomes problematic.

Advantages of Dynamic Routing

• Easy to configure, also easy to maintain.
• When changes occur in the network topology, the dynamic protocol does not need further configuration.
• There are very few chances of the wrong configuration in a large network.
• With the growing network, maintenance is not as tricky as static routing.
• Whole network knowledge is not required for maintenance.

Disadvantages of Dynamic Routing

• Dynamic routes advertise their routing table over the network, resulting in a security hazard to the network.
• The dynamic routing protocol requires a continuous handshake between each router, so it requires more bandwidth.
• The path for sending data using a dynamic routing protocol is not known.
• Complexity does not depend on the network size.