  Nowadays, routing protocols have become a crucial part of the modern
communication networks. A routing protocol's responsibility lies in determining
the way routers communicate with each other in order to forward any kind of
packets, from a source to a destination, using the optimal path that would
provide the most efficiency. There are many routing protocols out there today,
some old and some new, but all are used for the same purpose. In general, to
ideally select routes between any two nodes on a computer network and
disseminate information. This paper takes into consideration four of such
routing protocols (RIP, OSPF, IS-IS and EIGRP), expresses them and analyzes
their way of operation. It also presents the results of a simulation, that took
place for the sole purpose of studying the behavior of those four protocols,
under the same circumstances, as well as the evaluation of the comparison with
one another based on the results of the simulation.
