Interdomain Internet Routing

This paper is a lecture series which explains the workings of inter- domain routing, which is the back bone of the internet. The interdomain routing protocol is called the border gateway protocol, which is used the route between domains. Since the main goal of the internet was to connect different networks together to form a large interconnected communication channel, there needed to be a way to route the packets from various domains and networks.

The internet is formed by different Automonous Systems including ISPs and campuses. The network within the ASes usually are routed by the ASes themselves, but the routing between the ASes were governed by policies and financial motivations. Thus a scalable protocol that is easily customizable between domains was created to allow ASes to easily configure what routes to broadcast. ultimately it costs money to transmit packets, so the least amount of traffic results in the most saved in earnings. This paper describes the different AS relationships and the route broadcast mechanisms that's resulting from that.

It was quite interesting reading about it. In all the previous networking classes or routing lectures and research papers, it always seems like the main focus is shortest path, or congestion control or flow control. But in reality, research is put into minimizing cost and maximizing profit.