What are the two types of Interior Gateway Protocols (IGP)?

Interior Gateway Protocols (IGPs) are used for routing within an autonomous system. The two primary types of IGPs are Distance Vector and Link State protocols.

Distance Vector protocols operate by having routers share their routing tables with neighboring routers. Each router calculates the best path based on the distance to the destination, typically measured in hops. Examples of Distance Vector protocols include Routing Information Protocol (RIP) and Interior Gateway Routing Protocol (IGRP).

Link State protocols, on the other hand, work by having routers share information about the state of their links to all other routers in the network. This enables each router to build a complete map of the network topology and calculate the shortest path to each destination based on that map. Examples of Link State protocols include Open Shortest Path First (OSPF) and Intermediate System to Intermediate System (IS-IS).

Choosing the correct identification of these protocol types is fundamental in understanding how inner network routing decisions are made.