To choose a routing protocol you should consider these factors:
Configuration
Efficiency
Size and topology
Explanation:
Configuration factor is that how easy is to configure and troubleshoot the protocol. Configuration is a factor need to be in count while selecting a routing protocol e.g. RIP V1, IGRP are easy to configure and OSPF V2 configuration is not simple.
Efficiency is that how fast it converges? How much bandwidth it uses? how much efficient is that protocol is? Convergence of IGRP is slow and for OSPF is quick.
Convergence: The process that a routing protocol goes through to alert all routers on the network of the next available path when the primary path becomes unavailable.
Size and topology means how much large network it can handle and what topology is using is the network a star? partial mesh? full mesh?
