What is OSPF? How it works?

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OSPF (Open Shortest Path First) is a routing protocol used to find the best path for data packets in a network.

OSPF is a link-state routing protocol that uses Dijkstra's algorithm to calculate the shortest path to each network.
It operates within an autonomous system (AS) and exchanges routing information using link-state advertisements (LSAs).
OSPF routers build a topology map of the network and use this information to determine the best path to each destination.
It supports VLSM (Variable Length Subnet Masking) and CIDR (Classless Inter-Domain Routing) for efficient IP address allocation.
OSPF uses cost metrics to determine the best path, with lower costs indicating faster or more reliable links.
Example: Router A receives LSAs from neighboring routers, calculates the shortest path to each network, and updates its routing table accordingly.

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