O'Reilly logo

CCNP ROUTE 642-902 Quick Reference by Denise Donohue

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Chapter 3. OSPF

OSPF Overview

OSPF is an open-standard, classless routing protocol that converges quickly and uses cost as a metric. (Cisco IOS automatically associates cost with bandwidth.)

OSPF is a link-state routing protocol and uses Dijkstra’s Shortest Path First (SPF) algorithm to determine its best path to each network. The first responsibility of a link-state router is to create a database that reflects the structure of the network. Link state routing protocols learn more information on the structure of the network than other routing protocols and thus can make more informed routing decisions.

OSPF routers exchange Hellos with each neighbor, learning Router ID (RID) and cost. Neighbor information is kept in the ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required