Abstract: “Efficient routing mechanism is a challenging issue for group oriented computing in Mobile Ad Hoc Networks (MANETs). The ability of MANETs to support adequate Quality of Service (QoS) for group communication is limited by the ability of the underlying ad-hoc routing protocols to provide consistent behavior despite the dynamic properties of mobile computing devices. This paper presents a study of one to one and many to many communications in MANETs and provides a comparative performance evaluation of Unicast and Multicast routing protocols. AODV and DSR are used as unicast protocols and MAODV and ODMRP are used as represent multicast routing protocols. Problems in ad hoc networks are the scarcity of bandwidth, short lifetime of the nodes due to power constraints, dynamic topology caused by the mobility of nodes. These problems put in force to design a simple, scalable, robust and energy efficient routing protocol. In this paper I will discuss different types of routing protocols for mobi”

Keywords: Routing, Mobile Ad-Hoc Networks.