International Journal of Modern Engineering Research (IJMER) www.ijmer.com Vol.2, Issue.6, Nov-Dec. 2012 pp-4180-4185 ISSN: 2249-6645 www.ijmer.com 4180 | Page Neha Gupta 1 , Manish Shrivastava 2 , Angad Singh 3 I.T. Department, Lakshmi Narain College of Technology, Bhopal, India 1 HOD, I.T. Department, Lakshmi Narain College of Technology, Bhopal, India 2 AP, I.T. Department, Lakshmi Narain College of Technology, Bhopal, India 3 ABSTRACT: Ad-hoc networking is a model in wireless device interactions, which represent that users wanting to communicate with each other form a temporary network, without any form of centralized administration. Each node participating in the network acts both as host and a router and must therefore is willing to forward packets for other nodes. For this purpose, a routing protocol is needed. This means that the routing protocol should try to minimize control traffic, such as periodic update messages. Cluster formation in Ad-hoc network is an important issue; Clustering in Mobile Ad Hoc Networks (MANETs) has many advantages compared to the traditional networks. But the highly dynamic and unstable nature of MANETs makes it difficult for the cluster based routing protocols to divide a mobile network into clusters and determination of cluster heads for each cluster. In recent years, several routing protocols and Cluster based protocols have been proposed for mobile ad hoc networks and prominent among them are DSR, AODV. This survey paper provides an overview of these protocols by presenting their characteristics, functionality, benefits and limitations and then makes their comparative analysis so to analyze their performance and compare some of existing works on clustering in MANETs. We categorize the works as Location based, Neighbor based, Power Based, Artificial Intelligence Based, Mobility based and Weight Based. We also present the advantages and disadvantages of these techniques and suggest a best clustering approach based on the observation. The objective is to make observations about how the performance of these protocols can be improved. Keywords: MANET; Routing Protocol; Clustering; AODV; CMDSR. I. INTRODUCTION Wireless communication between mobile users is becoming more popular than ever before. This due to recent technological advances in laptop computers and wireless data communication devices, such as wireless modems and wireless LANs. This has leaded to lower prices and higher data rates, which are the two main reasons why mobile computing continues to enjoy rapid growth. Starting from the development of the packet radio networks (PRNET) in the 1970s and survivable adaptive networks (SURAN) in the 1980s to the global mobile (GloMo) networks in the 1990s and the current mobile ad hoc networks (MANET) [1], the multi-hop ad hoc network has received great amount of research attention. Mobile Ad hoc Network (MANET), set of wireless mobile node forming a temporary network without the aid of any infrastructure or centralized control. Flexibility and Simplicity of adhoc network attracted everyone and solved many problems of communication where infrastructure establishment/reestablishment is not easy task, such as Rescue area, Military operations, creates these components, incorporating the applicable criteria that follow. Modern research area in ad hoc networks has paying attention on MAC and routing strategy. For the reason that of shared wireless broadcast medium, contention, near and for and hidden terminals are common in ad hoc networks and hence MAC demands significant improvement and routing is another issue especially in multi-hop environment. Routing is also an interesting issue as routes are typically multi-hop. An ad-hoc network has certain characteristics, which imposes new demands on the routing protocol. The most important characteristic is the dynamic topology, which is a consequence of node mobility. Nodes can change position quite frequently, which means that we need a routing protocol that quickly adapts to topology changes. The nodes in an ad-hoc network can consist of laptops and personal digital assistants and are often very limited in resources such as CPU capacity, storage capacity, battery power and bandwidth. Instead the routing protocol should be reactive, thus only calculate routes upon receiving a specific request. Generally, traditional routing protocols that are used in wired networks can’t support routing in fixed wireless networks and mobile networks with fixed access points. Only one-hop routing is required over a link in a wireless network with fixed access points and many fixed wireless network. Routing in mobile ad hoc networks and some fixed wireless networks use multiple-hop routing. Routing protocols for this kind of wireless network should be able to maintain paths to other nodes and in most cases, must handle changes in paths due to mobility. Traditional routing cannot properly support routing in a MANET. Much wireless technology is based upon the principle of direct point-to-point communication. Popular solutions like Group Standard for Mobile communications (GSM) and Wireless Local Area Network (WLAN) both use an approach where mobile nodes communicate directly with some centralized access point. These types of networks demand centralization for configuration and operation. Contrary to this model is the multi-hop approach. In multi- hop scenarios, nodes can communicate by utilizing other nodes as relays for traffic if the endpoint is out of direct communication range. A mobile ad-hoc network, MANET [2], uses the multi-hop model. These are networks that can be set up randomly and on-demand. They should be self configuring and all nodes can be mobile resulting in a possibly dynamic network topology. 1.1 Ad-hoc networks Centralized networks, such as GSM, cannot be used in all situations. Significant examples of such scenarios Survey of Routing Scheme in MANET with Clustering Techniques