Week 9 LSP Flashcards
LSRP?
Link State Routing Protocol
What is Link State Routing Protocol?
A distributed DB Algorithm
Steps to DB Algorithm?
- Each router is responsible for meeting its neighbors and learning who they are
- Each router constructs a LSA which contains a list of the neighbors (links) and costs to them.
- The LSA is sent to all routers in the AS and each router stores the most recent LSA from all other routers.
- Each router now computes best routes to all networks based on the LSA information.
What is LSA?
Link State Advertisement
Distance Vector?
Entire routing table is sent as an update
Periodically sends update at every 30 or 90 seconds. Consumes more bandwidth
Update are broadcast or multicast
Updates are sent to directly connected neighbor only
Routers don’t have end to end visibility of entire network
Link State?
Updates are incremental, and entire routing table is not sent as update
Updates are triggered, not periodic. Consumes less bandwith
Updates are multicast
Update are sent to entire network
No routing loops
Examples of Distance Vectors?
RIP, IGRP
Examples of Link State?
OSPF, IS-IS
OSPF?
Open Shortest Path First
What kind of protocol is OSPF?
Link State Protocol
Link State routing protocols allow routers to?
Share a common view of the entire network
Each router sends out a?
LSAs describing its attached links to all routers in an area
Each router needs to hold a ?
Topological Database of the entire area
What routing algorithm is used by OSPF?
Shortest Path First (SPF)
Also known as Dijkstra
Reason to implement OSFP in a hierarchical design?
Decrease routing overhead
Speed up confergence
Confine network instability to single areas of the network