The IGP vs BGP debate has been ongoing in the networking community for some time now. The Interior Gateway Protocol (IGP) and Border Gateway Protocol (BGP) are both protocols that are used in routing internet traffic, but they differ in many ways.
To put it simply, an IGP is used within a network, while BGP is used between networks. An IGP is typically used to exchange routing information between routers in the same autonomous system (AS). On the other hand, BGP is used to exchange information between routers in different ASes.
One of the main arguments in favor of IGPs is that they are easier to configure and maintain compared to BGP. IGPs are link-state protocols that enable routers to build an accurate and complete picture of the network topology. This makes it easier for network administrators to troubleshoot and optimize network routes.
BGP, on the other hand, is a path-vector protocol that involves more complex configuration and maintenance. BGP requires careful planning to prevent routing loops and other issues that can arise when routing information is exchanged between different ASes.
Despite the challenges associated with BGP, many experts argue that it is a necessary protocol for large-scale networks. BGP provides greater flexibility and control over routing policies, which can be crucial for organizations that need to manage complex routing environments.
In an article for Network World, network consultant Ivan Pepelnjak argued that BGP is essential for large enterprise networks because it allows them to connect to multiple service providers and take advantage of diverse routing paths. However, Pepelnjak also acknowledged that there are situations where an IGP is sufficient, such as small enterprise networks or within a single service provider network.
Similarly, networking expert Ron Bonica argued in a blog post that BGP is necessary for the internet to function properly. Bonica stated that BGP provides the means for independent networks to connect and exchange traffic without relying on a central authority.
In conclusion, the IGP vs BGP debate comes down to the specific needs of each network. IGPs are simpler, easier to configure, and maintain, making them a good choice for smaller networks or for routing within a single AS. However, for larger networks or for routing between different ASes, BGP provides greater flexibility and control. Ultimately, it is up to network administrators to weigh the pros and cons of each protocol and choose the one that best meets their needs.