International Journal of Emerging Technology and Advanced Engineering Website: www.ijetae.com (ISSN 2250-2459, Volume 2, Issue 4, April 2012) 242 Comparative analysis of QoS routing protocols in MANETS: Unicast &Multicast M. Vijaya Lakshmi 1 , Dr. S. Venkatachalam 2 1 Assoc. Prof., E.C.E. Dept, G.N.I.T.S., Hyderabad 2 Prof., E.C.E. Dept., C.V.R.College., Hyderabad 1 mvlakshmi_gnits@yahoo.co.in 2 sv_chalam2003@yahoo.com Abstract— In mobile ad hoc networks (MANETs), the provision of quality of service (QoS) guarantees is much more challenging than in wire line networks, mainly due to node mobility, multi hop communications, contention for channel access, and a lack of central coordination. The difficulties in the provision of such guarantees have limited the usefulness of MANETs. in the last decade, much research attention has focused on providing QoS assurances in MANET protocols. In this paper we have analysed different types of routing protocols and QoS metrics in MANETS. Keywords— MANETS, Qos, unicast rouing protocols, multicast Routing protocols. I. INTRODUCTION Wireless communication technology have been developed with two primary models one is fix infrastructure based model in which much of the nodes are mobile and connected through fixed backbone nodes using wireless medium. Another model is Mobile Ad-hoc network .Mobile Ad-Hoc Networks (MANETs) are comprised of mobile nodes (MNs) that are self-organizing and cooperative to ensure efficient and accurate packet routing between nodes (and, potentially, base stations).Fig1. shows the structure of MANETS. There are no specific routers, servers, access points for MANETs. Because of its fast and easy of deployment, robustness, and low cost, Typical MANETs applications could be find in the following areas like Military applications (i.e. a temporary network in the battlefield), Search and rescue operations, Temporary networks within meeting rooms, airports, Vehicle-to-vehicle communication in smart transportation, Personal Area Networks connecting mobile devices like mobile phones, laptops, smart watches, and other wearable computers etc. Design issue for developing a routing protocol for wireless environment with mobility is very different and more complex than those for wired network with static nodes [1]. Main problem in mobile ad-hoc network are limited bandwidth and frequent changes in the topology. Routing protocols for MANETs could be differ depending on the application and network architecture. Routing protocols typically fall under two classifications, first one is Unicast routing protocol, second one is Multicast routing protocol [4]. Different routing protocols try to solve the problem of routing in mobile ad hoc network in one way or the other. It observes that any one protocol cannot fit in all the different scenarios, different topologies and traffic patterns of Mobile Ad-Hoc Networks applications. For instance, proactive routing protocols are very useful for a small scale MANETs with high mobility, while reactive routing protocols are very useful for a large-scale, MANETs with moderate or less topology changes. Hybrid routing protocol attempts to strike balance between the two such as proactive for neighborhood, reactive for far away [2]. Figure 1: Mobile Ad Hoc Networks-MANETs. In mobile ad hoc networks (MANETs), the provision of quality of service (QoS) guarantees is much more challenging than in wire line networks, mainly due to node mobility, multi hop communications, contention for channel access, and a lack of central coordination.