Difference between Distance vector & Link State protocol

Distance Vector Protocol :


• Entire routing table is sent as an update

• Distance vector protocol send periodic update at every 30 or 90 second

• Update are broadcasted

• Updates are sent to directly connected neighbor only

• Routers don't have end to end visibility of entire network.

• Distance vector routing protocol network may have patch in network carrying wrong information

• It is proned to routing loops

• Routing loop avoidance Mechanism used are as below :

1> Max Hop Count
2> Spliti horizon
3> Route poisoning
4> Hold down Timer


• Distance vector routing protocol has slow convergance due to periodic update.


• Eg. RIP ,IGRP , BGP .






Link state protocol :


• Updates are incremental & enitire routing table is not sent as update

• Updates are triggered not periodic 

• Updates are multicasted

• Update are sent to entire network & to just directly connected neighbor

• Updates are carry SPF tree information & SPF cost Calculation information of entire topology

• Routers have visibility of entire network of that area only.

• No routing loops

• Convergance is fast because of triggered updates.

• Eg. : OSPF , IS-IS