What is IGP (Interior Gateway Protocol)?

IGP is a protocol used in a company, organization, or school environment, that is, in an autonomous system (AS).

What is IGP (Interior Gateway Protocol) on the Network?

IGPs are inside routing rules. This is because they work inside a routing area.

These rules create and keep routing information. They also make the base shape of an Independent System (AS).

For instance, they are used in big networks like ISPs. In the end, they give strength and quick recovery. They also provide traffic improvement.

Independent Systems are routing areas. Simple examples are a company’s inside network or an ISP’s own network. It is key for an ISP network to work well.

It must also be strong and safe. So, IGP rules are made to fix these needs.

Lastly, these rules are split into two types. The first type is distance-vector rules. The second type is link-state rules.

Distance-Vector Protocols

The distance-vector rule does not think about a data packet’s parts. Instead, it only counts the steps to the end place.

So, it picks the shortest way the packet must go. But, this rule group has some bad sides.

Still, it is straightforward to use. Because of that, it is very suitable for small networks. It is perfect for plain networks made of a few computers.

Link-State Protocols

Link-state rules think about many things when choosing. For instance, the speed of connecting lines changes this choice.

So, the best possible way for the data is picked. Businesses and internet firms often use IGP on their inside networks.

RIP, EIGRP, IGRP, OSPF, and IS-IS are famous types of these rules. Their main job is to find the shortest way. Because of this, they use the Bellman-Ford method.

This means no single router knows the whole network. Instead, it only gets information from its nearby friends. Routing lists are constantly being refreshed by sharing data packets.

Difference Between IGP and EGP

The main difference between IGP and EGP is how far they work. For instance, IGPs like OSPF and EIGRP work inside the exact Independent System.

They help share information between inside routers. This lets them make good choices using measures.

So, network traffic is improved and stability is raised. Unlike this, EGPs work between different systems. BGP, especially, makes up the base of the Internet.

It is needed to let talk between different networks. It also makes rule-based routing possible. In short, IGPs are in charge of inside performance. EGPs, on the other hand, allow worldwide linking and talking.