IACSIT International Journal of Engineering and Technology, Vol.3, No.2, April 2011 Abstract—A recent trend in ad hoc network routing is the reactive on-demand philosophy where routes are established only when required. Most of the protocols in this category, however, use single route and do not utilize multiple alternate paths. Major hurdle in communication via Ad hoc networks is their power limitations. As most of them use battery power and also are moving so there is always limitation of battery power. This Paper proposes a new scheme designed to minimize power consumption and to increase network lifetime. This will be incorporated on PAMAS as an extension to existing scheme. Index Terms—Ad Hoc Network, Routing protocol, Power, PAMAS I. INTRODUCTION A network is a series of interconnected nodes and Wireless networking is an emerging technology that allows users to access information and services electronically, regardless of their geographic position. Mobile Ad-hoc Network (MANET) is a collection of mobile nodes, which communicate with each other using wireless links in an infrastructure less network with no centralized administrative support. The end units in such networks are computers used to communicate among units on the move and need to reliably furnish this capability in the face of natural and man-made hostile environment [6, 7, and 12]. Commercial scenarios for ad hoc wireless network include conferences/meetings, Emergency services, Law enforcement. Main application of MANET is in emergency rescue operation and battle fields and many of the small combatants rely on communication devices that run on batteries, there is clear need to make MAC protocols both power and mobility aware [2,11,17,18]. Nodes in such network are highly mobile or stationery. Most work on Power efficient Protocol considered only static ad-hoc network. But in military application mobility is expected, so it is important that protocol should be power and mobility aware [9]. Current challenges in Power Aware protocols are following: • Multicast[13] • QOS Support [16 ] • Power -aware routing[2] • Location-aided routing[14] In a MANET, wireless communication involves usage of a transceiver at the source, intermediate, and destination nodes. The transmitter sends control, route request and response, as Manuscript received October 26, 2010 Divya Sharma is with the Institute of Technology and Management University, Gurgaon-122017 INDIA (phone: 01744-238222; e-mail: divya84kkr@ gmail.com). Ashwani Kush is with the Department of Computer Science, University college, Kurukshetra University, 132119 INDIA (E-mail: akush20@ gmail.com). well as data packets originating at or routed through the transmitting node. The receiver is used to receive data and control packets - some of which are destined for the receiving node and some of which are forwarded. A wireless network interface has five possible energy consumption states (six including the off state). a) Transmit state for transmitting data, control and routing packets b) Receive state is for receiving data, control and routing packets. c) In the idle state, which is the default state for ad hoc environment, the interface can transmit or receive packets. d) The sleep state has extremely low power consumption as the interface can neither transmit nor receive in this state. e) Lastly, a card can enter a reduced energy discard state while the media carries uninteresting traffic. The decision to enter the reduced energy discard state is made by the non-destination nodes in the range of the sender. This decision is based on the packet size information in the RTS (request to send) control packet that is exchanged between the sender and the receiver at the start of packet transfer. The reduced energy state uses slightly less power than the idle state, but significantly more than that used in the sleep state [19]. An effort has been made in this paper to provide some improvement for PAMAS protocol. The algorithm will improve power saving feature of PAMAS. Rest of the Paper is organized as: In Section 2, A brief review of the two existing protocols have been done. Section 3 emphasizes the problem faced in the existing PAMAS protocol. In section 4 modifications to PAMAS has been proposed. Conclusion is given in the last section. II. RECENT WORK The Power Aware Ad hoc routing protocol enables dynamic, multi hop routing between participating nodes wishing to establish and maintain an ad hoc network. They allows mobile nodes to maintain routes to destinations with more stable route selection but designing power aware routing protocols has attracted a lot of attention for prolonged network operational time. Design objective of power aware protocols is to select energy efficient routes and simultaneously minimizing the overhead incurred in the selection of the routes. Some routing algorithms given by [20, 21] can optimize the energy use with a global perspective. But these algorithms cause expensive overheads for gathering, exchanging and storing the state information of a node. These algorithms can be improvised in order to make them scalable .Karn[1] Proposed Multiple Access with Collision Avoidance [MACA] for use in packet radio as an alteration to the traditional Carrier Sense Multiple Access[CSMA] media access scheme[1]. MACA is Power and Mobility Aware Protocol for Ad Hoc Network Divya Sharma and Ashwani Kush 161