Behind the Scenes : Open Shortest Path First Protocol

Implementation of OSPDF
  • OSPF is used to find the best path between the source and the destination router using its own Shortest Path First. Dijkstra’s algorithm is widely used in the routing protocol required by the routers to update their forwarding table.
  • It provides the shortest cost path from the source router to other routers in the network.
  • Also, the protocol recalculates routes when the network topology changes by using Dijkstra’s algorithm and minimizes the routing protocol traffic that it generates.
  • As a link-state routing protocol, OSPF maintains link-state databases, which are really network topology maps, on every router on which it is implemented. The state of a given route in the network is the cost, and OSPF algorithm allows every router to calculate the cost of the routes to any given reachable destination.
  • The Link State Database (LSDB) contains the link state advertisements sent around the ‘Area’ and each router holds an identical copy of this LSDB. The router then creates a Shortest Path First (SPF) tree using Dijkstra’s algorithm on the LSDB and a routing table can be derived from the SPF tree which now contains the best route to each router.



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Technological Enthusiast , Like to express what is need of time, Relates real world to philosophical insights