Nodes In Ad-hoc Network Research Articles

An efficient quantum based routing protocol with local link failure recovery algorithm for manet

The mobility factor of the nodes in a mobile Ad Hoc networks (MANET) changes the network topology leading to changes in size of the network. As the topology changes, link failure between the nodes takes place due to several reasons like channel interference and dynamic obstacles that give rise to severe performance degradation. Scalability and link failure recovery are the main criteria that will determine the performance of the network in terms of quality of service (QoS). While having different type of nodes, both mobile and immobile, that have several performance severity related to data transfer which is similar to the one in industrial parameter reporting and data logging, there exists a need to overcome performance related issues such as relatively faster and secured data transfer within the set of nodes. We developed the Quantum based Routing protocol (QRP) associated with Local Link Failure Recovery Algorithm (LLFR). The QRP is a routing protocol that uses DSR and AODV as an underlying protocol to improve the QoS in scalable wireless network. The QRP and LLFR establish link failure recovery spontaneously at the point of link breakage. The performance parameters like; packet delivery ratio, throughput, average end to end delay and routing overhead of the routing protocol QRP with LLFR is analyzed using NS2 simulator. Keywords: Ad Hoc Network, Link Failure, Routing Protocols, Scalability, Quality of Service.

Mobile Adhoc Routing Scheme in Reducing Energy Consuming

Mobile Ad hoc network, the author of this paper the energy consumption of a larger problem, analyses the reasons of large energy consumption. Mobile Ad Hoc network node has very limited resources, especially energy, through the design of effective power control strategy combined with routing to reduce the network energy consumption is very important and necessary. And as the goal, put forward the improvement strategy, proposed further reduce routing mechanism in mobile Ad-hoc energy costs, simulation and analysis show that the advantages of this solution.

LAR-1: Affirmative influences on Energy-Conservation and Network Lifetime in MANET

Nowadays, reduction of energy-consumption in Mobile Ad-Hoc Networks (MANETs) has been a herculean task. The LAR-1 position-based scheme in Ad-Hoc networks has recently invoked interest in the domain of energy conservation as it extends the network lifetime of the networks. The main objective of this new approach is, to achieve energy-aware routing by utilizing the sleep mode condition of mobile nodes in MANETs. In this paper, developments of performance-metrics using this new approach have been presented. Amazing results have been achieved through energy-aware routing by utilizing the sleep mode condition of mobile nodes in Ad-Hoc Networks. Using these developments, this approach has been found to be better than other protocols like DSR in networks.

Wave-propagation management in indoor environments using micro-radio-repeater systems

This paper investigates the ability of micro-radio repeaters for managing wave propagation by enhancing signal coverage for the nodes of a mobile ad-hoc network in a complex environment. Such radio repeaters can be considered to be scatterers with a large radar cross section (RCS). Strategically positioning them enables a chain of line-of-sight (LoS) propagation between the transmitter and receiver when the straight signal path is blocked by obstacles such as walls. To specify repeater parameters, wave propagation in various hallway junctions were analyzed using a ray-tracing method that accounted for reflection, penetration, and diffraction. By adding the repeater model to such propagation models, the ability of micro-radio-repeater systems to enhance wave propagation in indoor environments was demonstrated. The results were verified with various measurement examples using a bench-top repeater system at 2.4 GHz. To allow multiple access through a single repeater, a simple repeater structure, composed of two omnidirectional antennas and one amplifier with sufficient gain, was considered. Measurement results indicated that in the chosen various indoor scenarios, a repeater system with an active gain of more than 35 dB with omnidirectional antennas could present scattering larger than typical building diffraction, and thus could enhance signal connectivity at 2.4 GHz.

EVALUATING THE PERFORMANCE OF THE LOCATION-AIDED ROUTING-1P ROUTE DISCOVERY ALGORITHM

Dynamic Routing Protocols (DRPs) are widely-used for routing information among mobile nodes in Mobile Ad Hoc Network (MANET) and establish and maintain connectivity within the network. A DRP comprises two main phases: route discovery and route maintenance. The route discovery phase involves transmission of large number of redundant control packets consuming significant portion of the nodes power and increase communication overheads. Recently, a new efficient and effective route discovery algorithm has been developed, namely, the LAR-1P algorithm, which combines two well-known routing protocols; these are: the Location-Aided Routing scheme 1 (LAR-1) and probabilistic algorithms. This study evaluates and compared the performance of the LAR-1P algorithm against the performance of a number of route discovery algorithms through simulation. For each simulation, the number of retransmissions and reachability are estimated and compared. The simulations results demonstrated that LAR-1P provides better performance than all other algorithms it is compared with, as it significantly reduces communication overheads while maintaining almost the same network connectivity.

Broadcasting Mechanism with Less Flooding Packets by Optimally Constructing Forwarding and Non-Forwarding Nodes in Mobile Ad Hoc Networks

Broadcasting Mechanism with Less Flooding Packets by Optimally Constructing Forwarding and Non-Forwarding Nodes in Mobile Ad Hoc Networks

Efficient topology control scheme for wireless ad-hoc networks

An ad-hoc network considers an automatic network formation and maintenance of critical services as nodes come closer or go far away from each other. There is no wired infrastructure or cellular network in wireless ad-hoc network. Each mobile node has an adjustable transmission range. A node n can receive signal from another node m if node n is within the transmission range of the sender m otherwise, two nodes communicate by relaying the message using intermediate nodes. In this paper, we studied how to construct a sparse spanner efficiently for wireless ad-hoc network topology. For any given pair of nodes there is a power efficient path. Power values may be assigned to the nodes in ad-hoc networks, to tackle the topology control issue. This paper considers topology control problems under optimisation objectives to include minimising the maximum power and also overall power. We have tackled the topology control problem, by formulating as a linear programming for the traffic loads and an optimal solution was computed. Theoretical analysis and simulation study verify that the proposed scheme is better up to some extent.

Enhanced Adaptive Acknowledgement Method for Detecting Malicious Nodes in MANETs

Mobile Ad hoc Network is a collection of mobile nodes that communicate with each other without base station. These networks are developed instantly or on-demand when some nodes come in the mobility range of each other and decide to cooperate for data transfer and communication. MANETs are more vulnerable to various types of attacks due to its deployment nature. The security in the mobile ad hoc network is very hard to achieve because of its fundamental characteristics such as dynamic topology, open medium, limited power, limited bandwidth and remote transmission. The prevention mechanisms like cryptography or authentication alone cannot detect malicious nodes in Ad-hoc networks. Hence we propose and implement a new intrusion detection system named Enhanced Adaptive Acknowledgement method specially designed for MANETs. Using MRA scheme, this method is capable of detecting malicious nodes even in the presence of false misbehavior report. Compared to other detection methods, this method is capable of detecting high malicious nodes and hence increases the security and network performances.

Performance and Comparative Analysis of ADSA in a Vehicular Network: MAC Approach in IEEE 802.11p

Vehicular network (VN) technologies have become an attractive area of attention all over the world. Two factors that have contributed in the development, design and implementation of the VN standards include the need to ensure safety and the need to consider road accident avoidance strategies. However, the innate dynamic and the high topological mobility of the nodes in Vehicular Ad Hoc Networks (VANETs) raise complex and challenging issues with the standard. One of the complexities is the problem posed by Doppler Effect (DE) resulting from the high mobility of the VANET nodes. In an attempt to compensate the induced Doppler Shift (DS), Automatic Doppler Shift Adaptation (ADSA) was recently introduced to combat DE in a VANET. ADSA proved to be more resilient and effective in term of Bit Error Rate (BER). Moreover, for realistic applications, BER tests alone are insufficient. Therefore, this work explores the strength of the refined ADSA method in terms of throughput and presents a comparative analysis of ADSA versus Adaptive Modulation Code (AMC) and Auto-Rate Fallback (ARF). Results from the analysis shows that the ADSA approach demonstrates strong robustness compared to AMC and ARF with up to 44 to 55% improvement in throughput and a 174 to 182% reduction in consumed time.

Investigation of traffic impact on RDCLRP

Routing fails frequently owing to scarce energy resources and movement of nodes in mobile adhoc network (MANET). This hampers the data flow continuity and limits the performance of routing protocol. Maintaining an uninterrupted flow of traffic is the key challenge in the design of efficient routing protocol. An algorithm RDCLRP (route discovery using cross layer routing protocol) is proposed to reduce discontinuity of data flow. An on-demand route is discovered in advance before route failure to avoid route instability. The modifications are made to the AODV protocol's route maintenance mechanism in order to develop RDCLRP. Three variants of proposed work are developed and their results are discussed. Performance of proposed algorithm is investigated for change in traffic. Proposed algorithm illustrates that the data flow discontinuity rate is reduced by 90% over AODV.

A time stamp-based elliptic curve cryptosystem for wireless ad-hoc sensor networks

Public key cryptography has been playing an important and vital role in providing security in various domains including secure electronic transactions in distributed environment and secure communication between different nodes in a wireless ad-hoc network. The security in wireless sensor networks is currently provided mostly through symmetric key cryptography. The proposed protocols in this domain are mainly based on the idea of keys before the deployment of the wireless sensor network. However, due to the limitation on memory resources of wireless sensor nodes, these protocols are not able to achieve perfect security and also face a key management problem in large scale wireless sensor networks. On the other hand asymmetric key cryptography offers flexibility to node and clean interface for the security component in the sensor network. This paper proposes a new mutual authentication and key management scheme for a particular session between any two corresponding nodes of a wireless sensor network based on elliptic curve cryptography with a novel time stamp mechanism. Nevertheless the same mutual authentication and key management scheme for a particular session in wireless sensor networks can be extended efficiently for a multi-session scenario in domain of wireless sensor networks or in the wired or wireless ad-hoc networks.

Congestion Controlled d-Adapt-OR for Adhoc Networks

Opportunistic routing scheme is used to route data packet from source to destination. Broadcasting nature of the wireless networks is utilized here to send data packets. A suitable forwarder node is selected from the neighboring node based on the rank ordering of the nodes. The nodes are ranked according to a score called Estimated Best Score (EBS). This score is calculated by considering the network congestion which is one of the major problems in adhoc networks. Probability of unsuccessful delivery of the packet become very less. Different types of packets are used to communicate between different nodes. A distributed and asynchronous routing scheme is introduced to route the packet. The proposed routing scheme doesn't require any initial knowledge about the network topology. Another problem with adhoc wireless networks is the presence of selfish nodes. For the successful delivery of the packet at the destination we have to avoid the presence of selfish nodes in the networks. So each node calculate the selfishness of its neighboring nodes. The data packet is forwarded by considering the selfishness of the node. I. Introduction Wireless adhoc networks are decentralized type of networks. A node in wireless adhoc networks communicate with the node which is in the range of the node. Wireless adhoc networks are considered in this work. Routing in adhoc networks is very important in order to communicate with the node which is not directly reachable. Different conventional routing scheme is now used to direct packet from source to destination. But most of them is not deal with the network congestion. They always result in unnecessary packet retransmission. Conventional routing scheme always find a fixed path along source to destination. So it always requires maintaining the knowledge about the network topology and statistics to find a path. Here a routing scheme called opportunistic routing is used. Opportunistic routing scheme doesn't require any previous knowledge about the networks and statistics. It dynamically route the packet from source to destination without any initial knowledge about the networks. This routing scheme exploits the broadcast nature and the opportunities available in the networks. It selects a node from its neighbors as next relay node based on some conditions. According to these conditions order the neighboring nodes and select one node as the relay node. And this process continues until it reaches the destination. The selection of next relay node may based on some geographical location or shortest path etc. Here proposed a routing framework called d-Adapt-OR that is distributed adaptive, asynchronous opportunistic routing scheme to route the packet. This routing scheme has low complexity and low overhead. While routing the routing scheme considered the congestion in the network and finds a path with less congestion. And it assumes no knowledge about network topology. One of the major problems in wireless adhoc networks is the presence of selfish nodes. A node is said to be selfish if it doesn't provides its own resources to forward others packet. But it takes the advantage of other node's resources and memory to forward its own packets. The nodes that drop the packet without forwarding it is a selfish node. A node may selfish even if it doing some other tasks at the packet arrival time. So the presence of selfish nodes reduces the packet success probability and deteriorates the performance of the network. So we have to avoid this type of nodes from the networks for improving the probability of successful delivery of the packet.

A Tutorial of Mobile Ad-Hoc Network (Manet) Routing Protocols

In mobile adhoc network nodes dynamically forms networks, there is no any central infrastructure, thus routing becomes a very important issue. Routing protocols used in mobile ad hoc networks (MANET) must adapt to frequent or continual changes of topology, while simultaneously limiting the impact of following these changes on wireless resources. This paper presents a comprehensive report and a comparative study of the different MANET routing protocols. The performance of such communication between nodes depends on various protocols. we have tendency to survey variety of the recent analysis results in routing space. In the following sections we have a tendency to present various existing routing protocols with their merits and demerits

Directed information dissemination in vehicular ad-hoc networks

In this article, we utilize the idea of multipoint relays (MPRs) found in literature (Jacquet et al. in Proceedings of IEEE INMIC, 2001), to propagate accident information in a restricted way (e.g., only backwards). We devise an algorithm to identify MPRs that are geographically situated behind a particular node using only its neighbor table, and speed information of the neighboring vehicles. With the identification of the backward MPRs, it is possible to restrict the information dissemination to vehicles behind a particular vehicular ad-hoc network (VANET) node only. This might benefit the approaching vehicles so that the driver could take preventive measures in real-time since he/she will have an indication of the severity of road conditions ahead. We assume that there exists an inter vehicular network using optimized link state routing (OLSR) where accident information can be propagated to all nodes using on-going OLSR control packets. We envision our application will run on top of existing routing protocols (e.g., OLSR), thereby resulting in very little integration effort, and retaining OLSR’s reduced network traffic advantage through the use of MPRs. We analyze our back MPR identification algorithm in a detailed manner. We also show that by using our approach the location of the accident alert instigator node could be pinpointed if a subset of the nodes in the same VANET know their geographical positions. We use VANET mobility models generated by SUMO into NS-3 for our simulations, and also perform preliminary experiments to verify the algorithm’s effectiveness. Our analysis and experiments show favorable results.

A tree-based mobility management using message aggregation based on a skewed wait time assignment in infrastructure based MANETs

For the effective mobility management of mobile nodes in Infrastructure-based Mobile Ad Hoc Networks, every mobile node is obliged to send a registration message to the Internet Gateway (IG) periodically. Not only do the registration messages and the additional control messages to establish paths from mobile nodes to the IG to send the registration messages incur a considerable amount of control overhead, but also they impose high traffic congestion on the mobile nodes in the vicinity of the IG which is referred to as the "funneling effect." The control overhead and the funneling effect make it hard to handle mobility management with little impact on the performance of a routing protocol. Therefore, in this paper we propose a tree-based mobility management approach using a message aggregation technique that employs a novel timing model suitable for tree topology, referred to as a skewed wait time assignment technique, in order to maximize message aggregation. Despite its superior performance, this wait time assignment technique differs from the other techniques in that it does not require clock synchronization over nodes. By resorting to simulations, we show that the proposed approach can significantly alleviate the funneling effect as well as improve the performance of mobility management compared with the Tree-based and Quasi-tree based mobility management schemes.

Practical Enhanced Topology Discovery Algorithm for MANET

In order to effectively manage the communication nodes in Mobile Ad Hoc Network (MANET), it is important to know the topology of such networks. Traditional Ad-hoc On-demand Distance Vector (AODV) protocol can not get the MANET topology due to the lack of the topology discovery mechanism. Aiming at this problem, an enhanced topology discovery algorithm based on AODV (AODV-TD) is proposed. AODV-TD can not only obtain the topology of dynamic network by topology discovery request, but also realize route discovery among nodes. Finally, the proposed algorithm is implemented on a hardware platform using CC1100, and the experiment results show that, even the network changes dynamically, AODV-TD can still discover the network topology rapidly and accurately, so that contribute to reducing the route discovery time and the RREQ forwarding packets.

Enhanced AODV for Mobile Ad-hoc Networks

A mobile ad-hoc network comprises of mobile nodes that can communicate with the nodes within their radio range and also with those which are outside range by using route discovery mechanisms. The nodes in an ad-hoc network can act as a host and also as a router that can route data to or from the other nodes. The topology of mobile ad-hoc networks changes dynamically which is mainly due to arrival or departure of nodes from the network. The nodes in ad-hoc network are self-adjusting and can adapt to the changes occurred in the topology. The main limitation of mobile ad-hoc networks is the energy constraints. There are three states of a node that results in energy consumption that are transmitting, receiving and idle state. The energy consumption of a node leads it to get down and makes it out of the network. This will lead to change in topology which incurs routing overhead when information about the down node has to be transferred to each node in the network. Again it will result in consumption of energy which incurs due to processing of these packets containing the information about the down node. In this paper we are presenting an enhanced on demand routing protocol in which each node uses a threshold value for energy and when the value of energy of that node reaches the threshold that node will not participate in the data transfer and when all the nodes in the network possess the set threshold value the threshold value is decreased. The enhanced protocol is based on Ad-hoc On Demand Distance vector (AODV) and hence named as Enhanced AODV (EAODV). In this paper the working of the EAODV is explained and also the simulation of the protocol is shown using the NS2 simulator. The paper also shows how this protocol is better than simple AODV based on different performance factors. The EAODV mainly concentrates on using the energy of nodes in an efficient manner so that the lifetime of a network can be increased.

Simulation and Performance Analysis of Reactive Routing Protocols

ad-hoc network is a collection of two or more devices equipped with wireless communications and having networking capability. The devices in the network can communicate with another node that is immediately within their radio range or one that is outside their range. The intermediate node is used to relay or forward the packet from the source to the destination. An Ad-hoc Network is a self- organizing and self-configuring wireless network. It is a temporary network established without the aid of stand-alone infrastructure. The topology of an ad-hoc network changes dynamically. The topology changes due to departure or arrival of a node. The nodes in mobile ad-hoc network acts as host as well as routers that routes the packets to the destination node. The mobile ad-hoc network is established for a single session and it does not require router of a base station. In this research two Reactive Routing (On-demand) protocols have been studied and compared with each other on various performance factors. The protocols that have to be examined are Dynamic Source Routing (DSR) and Ad-hoc On Demand Distance Vector (AODV).The main part of the research is the energy consumption by these protocols to transfer the data from the source to destination. Various other factors have also been examined in this paper based on which we come to know which protocol can be used according to our requirements and produces better results. KeywordsDSR, Mobile Ad-hoc Network

Link Analysis of Mobile Nodes in Ad Hoc Network Using Ricean Fading Channel Model

Communication channels are one of the important components of the wireless mobile ad hoc network. The link connectivity among mobile nodes moving in these channels can be measured through various performance metrics. This paper analysis the link connectivity of mobile nodes in one of the well known channel model, the Ricean fading channel, in which a strong dominant signal component is always present among several multipath signals received by receiver. Two performance matrices have been used to evaluate the link analysis of nodes. These are Link duration and Link ratio. It is discovered that the link duration is dependent on Ricean Factor K where as Link ratio shows irregular results, which represent true picture of link connectivity in the presence of fading.

Effectual Routine for Trilateral Authentication in Ad-hoc Networks using Multicast Conventions

Ad-hoc networks have mass of applications; though, a dynamic problem regarding their security aspects must be answered in order to realize these applications. Validating the source and ensuring the integrity of the message traffic become an essential constraint for the operation and management of the network. We focus on the security problem of protecting the network connectivity between nodes in ad-hoc network. New nodes start to contribute in the network as guests; they can only become full members with a network signed certificate after their authenticity has been warranted by some other members. In this paper we introduce routine of multicast Protocol for tired authentication between the multilevel of ad-hoc network. In this proposed protocol Central Authority with trilateral authentication for managing key authentication and certification process which leads to increase the security and reliability of the network.