Foundation Topics

Routing protocols define various ways that routers chat among themselves to determine the best routes to each destination. As networks grew more complex over time, routers gained both processing power and RAM. As a result, engineers designed newer routing protocols, taking advantage of faster links and faster routers, transforming routing protocols. This chapter follows that progression to some degree, starting with an introduction to routing protocols. Following that, the theory behind distance vector routing protocols, used with the earliest IP routing protocols, is explained. The final section of this chapter examines the theory behind link-state routing protocols, which is used by some of the more recently defined routing protocols.