Basics of internet network structure.

Any computer network faces a tradeoff. Adding more links creates more capacity and makes the network more robust, since packets can be routed around link failures. However, links are infrastructure and therefore expensive. The internet strikes a balance between the extremes of a fully-connected (and absurdly expensive) network and a minimally-connected (but fragile) network.

Credits: Talking: Geoffrey Challen (Assistant Professor, Computer Science and Engineering, University at Buffalo). Producing: Greg Bunyea (Undergraduate, Computer Science and Engineering, University at Buffalo).

Part of the https://www.internet-class.org online internet course. A blue Systems Research Group (https://blue.cse.buffalo.edu) production.