ZRP versus AODV and DSR : A Comprehensive Study on ZRP Performance

Mobile Ad Hoc Networks (MANETs) are networks of mobile computing nodes (e.g. portable computers, PDAs etc.) equipped with wireless interfaces and communicating with each other without relying on any infrastructure. In these networks each mobile node may act as a client, a server and a router. MANETs have emerged to fulfill the need for communication of mobile users in locations where deploying a network infrastructure is impossible, or too expensive, or simply is not available at that time. Characteristic scenarios for MANETs are disaster relief operations, battlefields and locations where infrastructure-based WLAN coverage (also called hotspots) is not provided and wireless WANs (e.g. GPRS/UMTS) are too expensive to use or too slow. Most of the research on MANETs has focused on issues dealing with the connectivity between mobile nodes in order to cope with the dynamism of such networks and the arising problems thereof. This dy namism is due to the mobility of nodes, the wireless chann el’s adverse and fast changing conditions and the energy limitations of mobile nodes, all of which lead to frequent disconnections and/or node failures. These research efforts have led to the creation of a sound technical basis for dealing with the aforementioned problems regarding node connectivity in MANETs (mainly through Zone Routing Protocol). However, solving the problems of connectivity alone is not sufficient for the adoption of MANETs. Since their basic role is to allow mobile users to exchange data and use each other’s services, there is also a need for architectures, mechanisms and protocols to tackle route failures and minimize the control overhead. One of well-known hybrid routing protocol for ad-hoc networks is Zone Routing Protocol (ZRP). However, in order to find its suitability, we needed to understand its behavior in various network sizes. So, in our survey we used QualNet 4.5.1 Network simulator to study the behavior of ZRP versus AODV and DSR. Their main characteristics have been presented and a thorough evaluation has been carried out for ZRP against DSR and AODV. Regretfully ZRP was not up to the task and it performed poorly throughout all the simulation sequences, hence putting itself out of competition. In particular, it demonstrated a really low packet delivery ratio when compared to DSR and AODV. From this survey, we could find that ZRP uses many control packets which are resulting in the increase of network load and decrease of network performance.