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CITL Tech Varsity, a leading institute for assisting academicians M.Tech / MS/ B.Tech / BE (EC, EEE, ETC, CS, IS, DCN, Power Electronics, Communication)/ MCA and BCA students in various Domains & …

CITL Tech Varsity, a leading institute for assisting academicians M.Tech / MS/ B.Tech / BE (EC, EEE, ETC, CS, IS, DCN, Power Electronics, Communication)/ MCA and BCA students in various Domains & Technologies from past several years.
DOMAINS WE ASSIST
HARDWARE:
Embedded, Robotics, Quadcopter (Flying Robot), Biomedical, Biometric, Automotive, VLSI, Wireless (GSM,GPS, GPRS, RFID, Bluetooth, Zigbee), Embedded Android.
SOFTWARE
Cloud Computing, Mobile Computing, Wireless Sensor Network, Network Security, Networking, Wireless Network, Data Mining, Web mining, Data Engineering, Cyber Crime, Android for application development.
SIMULATION:
Image Processing, Power Electronics, Power Systems, Communication, Biomedical, Geo Science & Remote Sensing, Digital Signal processing, Vanets, Wireless Sensor network, Mobile ad-hoc networks
TECHNOLOGIES WE WORK:
Embedded (8051, PIC, ARM7, ARM9, Embd C), VLSI (Verilog, VHDL, Xilinx), Embedded Android
JAVA / J2EE, XML, PHP, SOA, Dotnet, Java Android.
Matlab and NS2
TRAINING METHODOLOGY
1. Train you on the technology as per the project requirement
2. IEEE paper explanation, Flow of the project, System Design.
3. Algorithm implementation & Explanation.
4. Project Execution & Demo.
5. Provide Documentation & Presentation of the project.



IEEE 2013 projects,M.Tech 2013 Projects,Final year Engineering Projects,Best student Projects,MS Projects,BE Projects,2013 2014 IEEE Projects

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  • 1. VANET NO PRJ TITLE ABSTRACT DOMAIN YOP 1 VMaSC: Vehicular multi-hop algorithm for stable clustering in Vehicular Ad Hoc Networks Clustering is an effective mechanism to handle the fast changes in the topology of vehicular ad hocnetworks (VANET) by using local coordination. Constructing stable clusters by determining the vehicles sharing similar mobility pattern is essential in reducing the overhead of clustering algorithms. In this paper, we introduce VMaSC: Vehicular Multi-hop algorithm for Stable Clustering. VMaSC is a novelclustering technique based on choosing the node with the least mobility calculated as a function of the speed difference between neighboring nodes as the cluster head through multiple hops. Extensive simulation experiments performed using ns-3 with the vehicle mobility input from the Simulation of Urban Mobility (SUMO) demonstrate that novel metric used in the evaluation of the least mobile node and multi-hop clustering increases cluster head duration by 25% while decreasing the number of clusterhead changes by 10%. VANET 2013 WIRELESS SENSOR NETWORK 2 Path Planning Algorithm for Mobile Anchor-Based Localization in Wireless Sensor Networks Localization is an essential issue in wireless sensor networks because many applications require thesensor nodes to know their locations with a high degree of precision. Various localization methodsbased on mobile anchor nodes have been proposed for assisting the sensor nodes to determine their locations. However, none of these methods attempt to optimize the trajectory of the mobile anchornode. Accordingly, this paper presents a path planning scheme, which ensures that the trajectory of themobile anchor node minimizes the localization error and guarantees that all of the sensor nodes can determine their locations. The obstacle-resistant trajectory is also proposed to handle the obstacles inthe sensing field. The performance of the proposed scheme is evaluated through a series of simulations with the ns-2 network simulator. The results show that the proposed path planningalgorithm yields both a lower localization error and a higher percentage of localized sensor nodes than existing path planning schemes. WIRELESS SENSOR NETWORK 2013 3 Real-Time Query Scheduling for Wireless Sensor Networks Recent years have seen the emergence of wireless cyber-physical systems that must support real-time queries of physical environments through wireless sensor networks. This paper proposes Real-Time Query Scheduling (RTQS), a novel approach to conflict-free transmission scheduling for real-time queries in wireless sensor networks. First, we show that there is an inherent tradeoff between latency and real-time capacity in query scheduling. We then present three new real-time schedulers. The nonpreemptive query scheduler supports high real-time capacity but cannot provide low response times to high-priority queries due to priority inversions. The preemptive query scheduler eliminates priority inversions at the cost of reduced capacity. The slack stealing query scheduler combines the benefits of the preemptive and nonpreemptive schedulers to improve the capacity while meeting the end-to- end deadlines of queries. We provide schedulability analysis for each scheduler. The analysis and advantages of our approach are validated through NS2 simulations. WIRELESS SENSOR NETWORK 2013 #56, II Floor, Pushpagiri Complex, 17th Cross 8th Main, Opp Water Tank,Vijaynagar,Bangalore-560040. Website: www.citlprojects.com, Email ID: projects@citlindia.com,hr@citlindia.com MOB: 9886173099 / 9986709224, PH : 080 -23208045 / 23207367 DOTNET – 2013 (Networking, Network-Security, Mobile Computing, Cloud Computing, Wireless Sensor Network, Datamining, Webmining, Artificial Intelligence, Vanet, Ad-Hoc Network)
  • 2. 4 EMBA: An Efficient Multihop Broadcast Protocol for Asynchronous Duty- Cycled Wireless Sensor Networks In this paper, we propose an efficient multihop broadcast protocol for asynchronous duty- cycledwireless sensor networks (EMBA) where each node independently wakes up according to its own schedule. EMBA adopts two techniques of the forwarder's guidance and the overhearing of broadcastmessages and ACKs. A node transmits broadcast messages with guidance to neighbor nodes. The guidance presents how the node forwards the broadcast message to neighbor nodes by using unicast transmissions. This technique significantly reduces redundant transmissions and collisions. The overhearing of broadcast messages and ACKs helps to reduce the number of transmissions, thus it minimizes the active time of nodes. We implement EMBA and conventional protocols of ADB and RIMAC broadcast in ns-2 simulator to compare their performance. The simulation results show thatEMBA outperforms ADB and RI-MAC broadcast in both sparse and dense networks. EMBA achieves lower message cost than the conventional protocols and significantly improves the energy efficiency in terms of both duty cycle and energy consumption.rks WIRELESS SENSOR NETWORK 2013 5 A new fuzzy based clustering algorithm for wireless mobile Ad-Hoc sensor networks Clustering is a significant mechanism that efficiently provides information for mobile nodes and improves the processing capacity of routing, bandwidth allocation, and resource management and sharing. Clustering algorithms can be based on criteria like battery power of nodes, mobility, networksize, distance, speed and direction. Above all, in order to achieve good clustering performance, overhead should be minimized, allowing mobile nodes to join and leave without disturbing the membership of the cluster while preserving current cluster structure as much as possible. This paper proposes a Fuzzy Relevance-based Cluster head selection Algorithm (FRCA) to solve problems found in existing wireless mobile ad hoc sensor networks, such as the node distribution found in dynamic properties due to mobility and flat structures and disturbance of the cluster formation. The proposed mechanism uses fuzzy relevance to select the cluster head for clustering in wireless mobile ad hocsensor networks. In the simulation implemented on the NS-2 simulator, the proposed FRCA is compared with algorithms such as the Cluster-based Routing Protocol (CBRP), the Weighted- basedAdaptive Clustering Algorithm (WACA), and the Scenario-based Clustering Algorithm for Mobile ad hocnetworks (SCAM). The simulation results showed that the proposed FRCA achieves better performance than other existing mechanisms. WIRELESS SENSOR NETWORK 2013 6 Game theory for misbehaving detection in wireless sensor networks Since sensor nodes have limited resources, cooperation may come at a significant expense; but, it gives also an intention to some nodes to act selfishly. This paper studies the application of game theoryto wireless sensor networks (WSNs). In particular, the study of selfish behavior in coverage maintenance protocol (CMP). The first objective of this work is the detection and prevention of selfish decisions using game theory. The second objective is to propose a solution to cope with selfishness and thereafter optimize network coverage. The last objective is the performance evaluation of the proposed solution using the NS-2 simulator, patched with CMP features, and a set of performance metrics such as: additional packet control overhead, false positive nodes and missed convicted nodes. WIRELESS SENSOR NETWORK 2013 7 Cluster head selection scheme for data centric wireless sensor networks Energy efficiency is main design issue for protocols of wireless sensor networks. Node clustering is an energy efficient approach for sensor networks. In clustering algorithms, nodes are grouped into independent clusters and each cluster has a cluster head. Data units gathered at base station depends upon lifetime of network. Cluster head selection is an important issue for energy efficiency of clusteringschemes. Intra cluster communication distance depends upon position of cluster head in cluster. In this paper, a new cluster head selection scheme is proposed. Proposed scheme can be implemented with any distributed clustering scheme. In proposed scheme, network area is divided into two parts: border area and inner area. Scheme restricts cluster head selection to only inner area nodes. Scheme is implemented and simulated with LEACH in NS-2. Simulation shows that proposed scheme significantly outperform LEACH for network lifetime and data gathering rate. WIRELESS SENSOR NETWORK 2013
  • 3. 8 Overlapped Schedules with Centralized Clustering for Wireless Sensor Networks The main attributes that have been used to conserve the energy in wireless sensor networks (WSNs) are clustering, synchronization and low-duty-cycle operation. Clustering is an energy efficient mechanism that divides sensor nodes into many clusters. Clustering is a standard approach forachieving energy efficient and hence extending the network lifetime. Synchronize the schedules of theseclusters is one of the primary challenges in WSNs. Several factors cause the synchronization errors. Among them, clock drift that is accommodated at each hop over the time. Synchronization by means ofscheduling allows the nodes to cooperate and transmit data in a scheduled manner under the duty cycle mechanism. Duty cycle is the approach to efficiently utilize the limited energy supplies for thesensors. This concept is used to reduce idle listening. Duty cycle, nodes clustering and schedulessynchronization are the main attributes we have considered for designing a new medium access control (MAC) protocol. The proposed OLS-MAC protocol designed with the target of making theschedules of the clusters to be overlapped with introducing a small shift time between the adjacentclusters schedules to compensate the clock drift. The OLS-MAC algorithm is simulated in NS-2 and compared to some S-MAC derived protocols. We verified that our proposed algorithm outperform these protocols in number of performance matrix. WIRELESS SENSOR NETWORK 2013 9 A Mobility-Aware Node Deployment and Tree Construction Framework for ZigBee Wireless Networks ZigBee is a specification formalized by the IEEE 802.15.4 standard for low-power low-cost low-data-ratewireless personal area networks. In ZigBee networks, a tree topology is often used to construct awireless sensor network for data delivery applications. However, delivery failures constantly occur inZigBee wireless applications due to node movements and network topology changes. The conventional route reconstruction method is designed to mitigate the effects of topology changes, but it consumes alarge amount of resources. In this paper, we exploit the regularity in node mobility patterns to reduce the frequency of route reconstructions and ensure that the transmission of data to mobile nodes is efficient. To increase the data delivery ratio and mitigate the effects of packet loss caused by the node mobility, we propose a ZigBee node deployment and tree construction framework. In particular, the frameworkconsiders the regularity in mobility patterns during the construction of the routing tree and deployment ofnodes. It also includes an overhearing mechanism for mobile nodes to further improve the data delivery ratio. We present details of the proposed algorithms for node deployment and tree construction in theframework. The effectiveness of network topologies constructed under the framework is demonstrated through comprehensive ns-2 simulations based on two real-world scenarios. The results show that our approach can construct ZigBee tree topologies with a high data delivery ratio and low routing overhead. WIRELESS SENSOR NETWORK 2013 10 A Cross-Layer QoS- Aware Communication Framework in Cognitive Radio Sensor Networks for Smart Grid Applications Electromagnetic interference, equipment noise, multi-path effects and obstructions in harsh smart gridenvironments make the quality-of-service (QoS) communication a challenging task for WSN-basedsmart grid applications. To address these challenges, a cognitive communication based crosslayerframework has been proposed. The proposed framework exploits the emerging cognitive radiotechnology to mitigate the noisy and congested spectrum bands, yielding reliable and high capacity linksfor wireless communication in smart grids. To meet the QoS requirements of diverse smart gridapplications, it differentiates the traffic flows into different priority classes according to their QoS needs and maintains three dimensional service queues attributing delay, bandwidth and reliability of data. The problem is formulated as a Lyapunov drift optimization with the objective of maximizing the weighted service of the traffic flows belonging to different classes. A suboptimal distributed control algorithm (DCA) is presented to efficiently support QoS through channel control, flow control, scheduling and routing decisions. In particular, the contributions of this paper are three folds; employing dynamic spectrum access to mitigate with the channel impairments, defining multi-attribute priority classes and designing a distributed control algorithm for data delivery that maximizes the network utility under QoSconstraints. Performance evaluations in ns-2 reveal that the proposed framework achieves requiredQoS communication in smart grid. WIRELESS SENSOR NETWORK 2013 11 Cocasting and power control for energy efficient information dissemination in WSNs This paper considers energy efficient information dissemination in Wireless Sensor Networks (WSNs) deploying co-operating nodes which by adjusting their transmission ranges minimize the total transmitted power in the network. Specifically, the design of routing protocols with a single relay node along a data path is proposed for multiple unicast sessions in a network with randomly distributed nodes. The protocols take advantage of topological diversity created by adapting the transmissionpower and exploit the benefits of network coding in a system where nodes are periodically generating data packets. Energy efficiency of the conventional, store- and-forward, and network coding based relaying schemes is analyzed in different propagation conditions and for various node densities. The best-case improvement in the energy efficiency achievable with network coding over store-and-forward is 25% for two node exchange of data. In WSNs, it is demonstrated through simulations that network coding offers realistically between 11% to 19% energy savings over the store-and-forward strategy. The deployment of the relaying node contributes to the improvement in energy efficiency over direct transmissions in a range of 80%. WIRELESS SENSOR NETWORK 2013
  • 4. MOBILE ADHOC NETWORK 12 Enhancing security features & performance of AODV protocol under attack for MANET In this paper, a novel security mechanism is presented to enhance security & performance of AODV (Adhoc On-demand Distance Vector) routing protocol under the attack for MANET (Mobile Ad-hoc Networks). The AODV routing protocol was initially developed without considering security in mind. So it is not able to defend against any kind of security attack. But there are many security mechanisms available that make AODV secure. However, by doing more research in this area, one major flaw in any of the existing secure routing protocols was discovered. That is security mechanisms that are available consume more processing power and required complex key-management system. Here, we present a novel security mechanism that integrates digital signature and hash chain to protect the AODV routing protocol that is capable of defending itself against both malicious and unauthenticated nodes with marginal performance difference. The proposed security mechanism was also simulated in the Network Simulator 2 (NS2) to show marginal performance difference under attack. MOBILE ADHOC NETWORK 2013 13 Wormhole Attack Avoidance Technique in Mobile Adhoc Networks Security is an essential service for wired and wireless network communication. This work concerned with a particularly sever security attack that affects the ad hoc networks routing protocols, called "wormhole attack". There are many solutions to detect and prevent this attack like packet leashes, cluster base, hop count analysis etc., but none of them is perfect solution. This paper contains a proposal for new technique for wormhole avoidance. Proposed technique has been implemented with NS2 simulator over the DSR protocol. This technique for wormhole avoidance addresses the malicious nodes and avoids the routes having wormhole nodes without affecting the overall performance of thenetwork. The performance metrics used for evaluating network performance are jitter, throughput and end to end delay. The performance of proposed techniques is good. MOBILE ADHOC NETWORK 2013 14 Performance analysis of an orthogonal rendezvous routing protocol for wireless mesh networks The increased usage of directional methods of communications (e.g. directional smart antennas [15], Free-Space Optical transceivers [19], and sector antennas) has prompted research into leveraging directionality in every layer of the network stack. In this paper, we learnt how the concept of directionality can be used in layer 3 to facilitate routing under contexts of 1) wireless mesh networks, 2) highly mobile environments, and 3) overlay networks through virtual directions. In the context of wireless meshnetworks, we introduce Orthogonal Rendezvous Routing Protocol (ORRP), a lightweight-but-scalablerouting protocol utilizing the inherent nature of directional communications to relax information requirements such as coordinate space embedding and node localization. The ORRP source and ORRP destination send route discovery and route dissemination packets respectively in locally- chosenorthogonal directions. We show that ORRP achieves connectivity with high probability even in sparsenetworks with voids. ORRP scales well without imposing DHT-like graph structures (eg: trees, rings, torus etc). We show that MORRP achieves connectivity with high probability even in highly mobile environments while maintaining only probabilistic information about destinations. MORRP scales well without imposing DHT-like graph structures (eg: trees, rings, torus etc). We will also show that high connectivity can be achieved without the need to frequently disseminate node position resulting increased scalability even in highly mobile environments. We will also evaluate the metrics ofreachability, state maintenance, path stretch, end-to-end latency and aggregate network good put under conditions of varying network densities, number of interfaces, and TTL values. MOBILE ADHOC NETWORK 2013 15 .MAZACORNET: Mobility Aware Zone based Ant Colony Optimization Routing for VANET Vehicular Ad hoc Networks (VANET) exhibit highly dynamic behavior with high mobility and random network topologies. The performance of Transmission Control Protocols in such wireless ad hoc networks is plagued by a number of problems: frequent link failures, scalability, multi-hop data transmission and data loss. To address these VANET routing issues, I have used the ideas from swarm intelligence. The Ant Colony Optimization (ACO), which is a branch of swarm intelligence, is the main source of my inspiration. I have designed an ant-based routing algorithm which addresses routing issues prevalent in VANETs: adaptivity, robustness and scalability. One attractive feature of ACO is that they provide multiple routes from source to destination, resulting in more robust network. In this work, together with ACO, I have used the ideas from zone routing protocols to develop my algorithm: Mobility Aware Zone based Ant Colony Optimization Routing for VANET that exhibits locality and scalability MOBILE ADHOC NETWORK 2013
  • 5. 16 Local node stability- based routing for Wireless MeshNetworks Thanks to their flexibility and their simple installation, Wireless Mesh Networks (WMNs) allow a low cost deployment of a network infrastructure. They can be used to extend the wired network coverage allowing connectivity anytime and anywhere. Network stability is a key performance metric in supporting real time communication over the network. Because of high bandwidth demand and dynamic traffic variation, several paths in WMNs are expected to be unstable. High levels of network instability can lead to interferences, packet losses and high delays. In this paper, we address the stability problem of WMNs; instability in these networks is caused mainly by link quality fluctuations and frequent route flapping. Indeed, most routing protocols try to optimize a routing metric locally or globally without considering network stability. First, we present the key factors that may cause network instability; then, we propose a new technique, called Local Node Stability-based Routing (LNS), using the entropy function (known as a measure of the uncertainty and the disorder in a system) to define a node stability. Simulation results show that the stability can be improved in WMNs using LNS compared to other routing schemes namely RLBDR, MIC and ETX. Keywords: WMN; Stability; Routing; Interferences; MOBILE ADHOC NETWORK 17 Energy-Efficient Routing Protocols for Wireless Sensor Network: A Survey Wireless sensor networks have recently received tremendous attention from both academia and industry because of their promise of numerous potential applications in both civilian and military areas. A wireless sensor network consists of a large number of small sensor nodes with sensing, data processing, and communication capabilities, which are deployed in a region of interest and collaborate to accomplish a common task, a sensor network has many unique characteristics, such as denser node deployment, higher unreliability of sensor nodes, asymmetric data transmission, and severe power, computation, and memory constraints, which present many new challenges for the development and eventual application of wireless sensor networks. In particular, sensor nodes are usually battery-powered and should operate without attendance for a relatively long period of time. In most cases, it is very difficult and even impossible to change or recharge batteries for these sensor nodes. Thus, energy-saving routing protocol in wireless sensor networks is necessary for increasing the network lifetime. In this paper we present a comparative study of different routing algorithms and analysis of same is presented in the paper. MOBILE ADHOC NETWORK 2013 Vehicular Technology 18 A Framework for Secure and Efficient Data Acquisition in Vehicular Ad Hoc Networks Intervehicular communication lies at the core of a number of industry and academic research initiatives that aim at enhancing the safety and efficiency of transportation systems. Vehicular ad hoc networks (VANETs) enable vehicles to communicate with each other and with roadside units (RSUs). Service-oriented vehicular networks are special types of VANETs that support diverse infrastructure-based commercial services, including Internet access, real-time traffic management, video streaming, and content distribution. Many forms of attacks against service-oriented VANETs that attempt to threaten their security have emerged. The success of data acquisition and delivery systems depends on their ability to defend against the different types of security and privacy attacks that exist in service-oriented VANETs. This paper introduces a system that takes advantage of the RSUs that are connected to the Internet and that provide various types of information to VANET users. We provide a suite of novel security and privacy mechanisms in our proposed system and evaluate its performance using the ns2 software. We show, by comparing its results to those of another system, its feasibility and efficiency. Vehicular Technology 2013 Parallel and Distributed SystemS 19 ALBA-R: Load- Balancing Geographic Routing Around Connectivity Holes in Wireless Sensor Networks This paper presents ALBA-R, a protocol for convergecasting in wireless sensor networks. ALBA-R features the cross-layer integration of geographic routing with contention-based MAC for relay selection and load balancing (ALBA) as well as a mechanism to detect and route around connectivity holes (Rainbow). ALBA and Rainbow (ALBA-R) together solve the problem of routing around a dead end without overhead-intensive techniques such as graph planarization and face routing. The protocol is localized and distributed, and adapts efficiently to varying traffic and node deployments. Through extensive ns2-based simulations we show that ALBA-R significantly outperforms other convergecasting protocols and solutions for dealing with connectivity holes, especially in critical traffic conditions and low density networks. The performance of ALBA-R is also evaluated through experiments in an outdoor testbed of TinyOS motes. Our results show that ALBA-R is an energy-efficient protocol that achieves remarkable performance in terms of packet delivery ratio and end-to- end latency in different scenarios, thus being suitable for real network deployments. Parallel and Distributed Systems 2013
  • 6. Mobile Computing 20 Proteus: Multiflow Diversity Routing for Wireless Networks with Cooperative Transmissions In this paper, we consider the use of cooperative transmissions in multihop wireless networks to achieve Virtual Multiple Input Single Output (VMISO) links. Specifically, we investigate how the physical layer VMISO benefits translate into network level performance improvements. We show that the improvements are nontrivial (15 to 300 percent depending on the node density) but rely on two crucial algorithmic decisions: the number of cooperating transmitters for each link; and the cooperation strategy used by the transmitters. We explore the tradeoffs in making routing decisions using analytical models and derive the key routing considerations. Finally, we present Proteus, an adaptive diversity routing protocol that includes algorithmic solutions to the above two decision problems and leverages VMISO links in multihop wireless network to achieve performance improvements. We evaluate Proteus using NS2-based simulations with an enhanced physical layer model that accurately captures the effect of VMISO transmissions. Mobile Computing 2013 21 Passive Measurement of Interference in WiFi Networks with Application in Misbehavior Detection We present a tool to estimate the interference between nodes and links in a live wireless network by passive monitoring of wireless traffic. This tool does not require any controlled experiments, injection of probe traffic in the network, or even access to the network nodes. Our approach requires deploying multiple sniffers across the network to capture wireless traffic traces. These traces are then analyzed using a machine learning approach to infer the carrier-sense relationship between network nodes. This coupled with an estimation of collision probabilities helps us to deduce the interference relationships. We also demonstrate an important application of this tool-detection of selfish carrier-sense behavior. This is based on identifying any asymmetry in carrier-sense behavior between node pairs and finding multiple witnesses to raise confidence. We evaluate the effectiveness of the tool for both the applications using extensive experiments and simulation. Experimental and simulation results demonstrate that the proposed approach of estimating interference relations is significantly more accurate than simpler heuristics and quite competitive with active measurements. We also validate the approach in a real Wireless LAN environment. Evaluations using a real testbed as well as ns2 simulation studies demonstrate excellent detection ability of the selfish behavior. On the other hand, the metric of selfishness used to estimate selfish behavior matches closely with actual degree of selfishness observed. Mobile Computing, 2013 22 Adaptive Position Update for Geographic Routing in Mobile Ad Hoc Networks geographic routing, nodes need to maintain up-to-date positions of their immediate neighbors for making effective forwarding decisions. Periodic broadcasting of beacon packets that contain the geographic location coordinates of the nodes is a popular method used by most geographic routing protocols to maintain neighbor positions. We contend and demonstrate that periodic beaconing regardless of the node mobility and traffic patterns in the network is not attractive from both update cost and routing performance points of view. We propose the Adaptive Position Update (APU) strategy for geographic routing, which dynamically adjusts the frequency of position updates based on the mobility dynamics of the nodes and the forwarding patterns in the network. APU is based on two simple principles: 1) nodes whose movements are harder to predict update their positions more frequently (and vice versa), and (ii) nodes closer to forwarding paths update their positions more frequently (and vice versa). Our theoretical analysis, which is validated by NS2 simulations of a well-known geographic routing protocol, Greedy Perimeter Stateless Routing Protocol (GPSR), shows that APU can significantly reduce the update cost and improve the routing performance in terms of packet delivery ratio and average end-to-end delay in comparison with periodic beaconing and other recently proposed updating schemes. The benefits of APU are further confirmed by undertaking evaluations in realistic network scenarios, which account for localization error, realistic radio propagation, and sparse network. Mobile Computing 2013