Static and Default Route:
In this article you will learn about static route and default route. Step by step guide to explain static route vs. default route.
The routers store receives the data packets and look for the destination Internet protocol (IP) address. Once the IP address or network of the destination is known, the router checks the routing table to select the best route through which the packet can be transferred.
The best route is selected based on the administrative distance and various cost metrics like bandwidth, congestion, and speed of the cable etc. generally there are static routes, Default routes and dynamic routes.
The static routes are manually entered by an administrator manually. An administrator has to enter all the routes manually in the router. All the routes entered by the administrator are stored in a routing table.
The administrator has to manually update the routing table in case of any changes in the network. If not updated, the router forwards the packets to the same interface even though the interface is down. This results in data loss. The static route must be configured on every router for gaining full connectivity between source and destination.
As the router does not exchange routing information, it is difficult to select the best path for the router by itself. The static routing consumes very few resources. The Static routing is good for the networks that are not changed very often.
The main disadvantage of static routing is that this is impractical for large networks. In case of any topology changes, the administrator has to manually update all the routers.
The administrative distance can be a number ranging from 0 to 255 and it defines the trust worthiness of a route. If administrative distance is small, the particular route is used to transfer the packets. The Administrative Distance of a static route is “1”. Hence static routes are given more preference than any other route when configured on a router.
The default routes are used when an IP packet does not find a route to its destination address from the routing table. Default route is a special case of static routing. If the default route is configured, and the route to the destination is not available in the routing table, packet is transferred to the next router based on the default route.
Any packet whose destination IP address is not known uses default route and forwarded to next router. The next router verifies the packet and treats it in the same way if it does not know the destination address. This process is repeated until the packet reaches the destination.
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- IGP Vs EGP
- What is Administrative Distance
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