Routing And Switching Questions Medium
A routing table is a data structure stored in a router that contains information about the available network paths and their associated metrics. It is used by the router to make routing decisions and determine the best path for forwarding network traffic.
The routing table consists of multiple entries, each representing a network destination. Each entry typically includes the destination network address, the next-hop router or interface to reach that destination, and the metric or cost associated with that path.
When a router receives a packet, it examines the destination IP address and looks up the corresponding entry in its routing table. It then uses the information in the routing table to determine the next-hop router or interface to forward the packet towards the destination.
The routing table is populated through various routing protocols, such as OSPF, EIGRP, or BGP, which exchange routing information between routers. These protocols use algorithms to calculate the best paths and update the routing table accordingly.
Routing decisions are made based on the information in the routing table, including the destination network address, the next-hop router or interface, and the associated metric. The router compares the destination address of the packet with the entries in the routing table to find the most specific match. It then selects the path with the lowest metric or cost as the best route.
In summary, a routing table is a crucial component of a router's operation, as it stores information about network paths and is used to make routing decisions. It enables routers to efficiently forward network traffic towards its intended destination.