OSPF Test Flashcards
What is OSPF?
OSPF (Open Shortest Path First) is a link-state routing protocol used in IP networks to dynamically determine the best path for data packets.
How does OSPF differ from RIP?
OSPF calculates the shortest path based on cost (bandwidth metric) while RIP uses hop count.
What is the purpose of the Router ID (RID) in OSPF?
The Router ID (RID) is a unique 32-bit identifier for an OSPF router.
What are Hello packets used for in OSPF?
Hello packets are messages used to discover neighbors and maintain relationships.
What is adjacency in OSPF?
Adjacency is a logical OSPF connection between routers that exchange routing updates.
What conditions must be met for OSPF routers to become neighbors?
Parameters such as area ID, subnet, hello/dead timers, and authentication must match.
What are the roles of the Designated Router (DR) and Backup Designated Router (BDR)?
DR and BDR are elected to reduce OSPF traffic in multi-access networks.
What do Database Description (DBD) packets do?
DBD packets are used to compare link-state databases between routers.
What is a Link-State Request (LSR)?
An LSR is a request for missing topology information from other routers.
What is a Link-State Update (LSU)?
An LSU is a response that contains detailed routing information.
What does a Link-State Acknowledgment (LSAck) confirm?
LSAck confirms the receipt of Link-State Updates (LSUs).
What is the Link-State Database (LSDB)?
LSDB is a complete map of the network maintained by each router.
What algorithm does OSPF use to compute the best paths?
OSPF uses the Dijkstra Shortest Path First (SPF) algorithm.
What is OSPF cost based on?
OSPF cost is determined by bandwidth; lower cost indicates a better path.
What is the Routing Information Base (RIB)?
The RIB is the router’s active routing table.
What is convergence in OSPF?
Convergence is the state where all routers agree on the best paths.
What is a Link-State Advertisement (LSA)?
LSA is a packet used to update LSDBs when changes occur.
Fill in the blank: OSPF continuously updates its LSDB whenever a change occurs, such as ______.
a link fails.
What is the first step in the OSPF process flow?
Router boots up & assigns a Router ID.
What happens after Hello packets are exchanged in the OSPF process?
Routers exchange topology information via LSAs.
What is the final step in the OSPF process flow?
OSPF continuously updates & maintains convergence.
