In this paper, the authors address the interoperability issues between Internal Border Gateway Protocol (IBGP) over other Interior Gateway Protocols (IGPs) by knowing the characteristics of the respective protocols and also study the efficiency of External Border Gateway Protocol (EBGP) as an Exterior Gateway Protocol (EGP). Furthermore, it shows how IGRP proves to be inefficient over other IGPs. Comparison of other IGPs and IBGP is made using administrative distance, metric, convergence and many more parameters in order to prove the loopholes in IGRP. The comparison of the distinguishing facts and features of these protocols has been tabulated for the steady reference. Demonstration through diagrams for different network architectures is being made.