What is the primary function of an EGP in networking?

The primary function of an Exterior Gateway Protocol (EGP) is to exchange routing information between different autonomous systems (AS). Each autonomous system represents a distinct network or group of networks under a common administration and routing policy. EGPs are essential for enabling communication and routing across these autonomous systems, which may have different routing structures and policies.

In practice, EGPs allow different ISPs (Internet Service Providers) or large organizations to establish and share routing information so that data can efficiently travel across various networks to reach its destination. The most well-known EGP is the Border Gateway Protocol (BGP), which and is widely used on the internet for this purpose.

Managing routing within a network is typically the role of Interior Gateway Protocols (IGPs), not EGPs. Troubleshooting network connectivity involves analyzing issues at various layers of the OSI model and does not specifically pertain to EGPs. Network address translation (NAT) is a technique used to map private IP addresses to a public IP address, which is unrelated to the functions of EGPs.