Question

For what purpose do routers use interior gateway protocols?

A) To communicate with external networks
B) To exchange routing information within a domain
C) To establish virtual private networks
D) To manage firewall rules

Answer 1

Interior gateway protocols are used by routers to exchange routing information within a single routing domain, helping to build consistent routing tables for efficient packet forwarding.

Step-by-step explanation:

Routers use interior gateway protocols (IGPs) to exchange routing information within a single routing domain or autonomous system (AS). This enables routers within the AS to build a consistent routing table, which they can use to determine the best paths for packet forwarding. Common IGPs include Routing Information Protocol (RIP), Open Shortest Path First (OSPF), and Intermediate System to Intermediate System (IS-IS).

The correct answer to the question is B) To exchange routing information within a domain. IGPs are concerned with managing routing information within a network as opposed to between different networks, which is the role of exterior gateway protocols (EGPs). IGPs are not used for establishing virtual private networks (VPNs), managing firewall rules, or directly communicating with external networks, though they can advertise routes that include paths to external networks.