Open Shortest Path First (OSPF) is a routing protocol for Internet Protocol (IP) networks. It uses a link-state routing (LSR) algorithm and falls into the group of interior gateway protocols (IGPs), operating within a single autonomous system (AS).

• Supports the CIDR addressing model
• Common in large enterprise networks
• Implements Dijkstra’s algorithm , also known as the shortest parth first (SPF) algorithm.
• Calculates the shortest route to a destination through the network.

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