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Enhanced Wireless Network Ad Hoc Pattern  [cached]
M. Kamalakannan,V. Khanaa
Research Journal of Applied Sciences, Engineering and Technology , 2012,
Abstract: Early simulation experience with wireless ad hoc networks suggests that their capacity can be surprisingly low, due to the requirement that nodes forward each others’ packets. The achievable capacity depends on network size, traffic patterns and detailed local radio interactions. This study examines these factors alone and in combination, using simulation and analysis from first principles. Our results include both specific constants and general relationship Scaling helpful in understanding the limitations of wireless ad hoc networks. We examine interactions of the 802.11 MAC and ad hoc forwarding and the effect on capacity for several simple configurations and traffic patterns. While 802.11 discovers reasonably good schedules, we nonetheless observe capacities markedly less than optimal for very simple chain and lattice networks with very regular traffic patterns. We validate some simulation results with experiments. We also show that the traffic pattern determines whether an ad hoc network’s per node capacity will scale to large networks. In particular, we show that for total capacity to scale up with network size the average distance between source and destination nodes must remain small as the network grows. Nonlocal traffic patterns in which this average distance grows with the network size result in a rapid decrease of per node capacity.
Enhanced Ad-Hoc on Demand Multipath Distance Vector Routing protocol  [PDF]
Sujata V. Mallapur,Sujata Terdal
Computer Science , 2010,
Abstract: Due to mobility in Ad-Hoc network the topology of the network may change randomly, rapidly and unexpectedly, because of these aspects, the routes in the network often disappear and new to arise. To avoid frequent route discovery and route failure EAOMDV was proposed based on existing routing protocol AOMDV. The EAOMDV (Enhanced Ad-Hoc on Demand Multipath Distance Vector) Routing protocol was proposed to solve the "route failure" problem in AOMDV. EAOMDV protocol reduces the route failure problem by preemptively predicting the link failure by the signal power received by the receiver (pr). This proposed protocol controls overhead, increases throughput and reduces the delay. The EAOMDV protocol was implemented on NS-2 and evaluation results show that the EAOMDV outperformed AOMDV.
Security Enhanced Adaptive TCP for Wireless Ad Hoc Networks  [PDF]
Waleed S. Alnumay
Journal of Information Security (JIS) , 2014, DOI: 10.4236/jis.2014.54019
Abstract: TCP is a reliable transport protocol designed to perform well in wired networks where packet losses are due congestion. However in wireless ad hoc networks, where packet losses are due to channel errors or link failures between mobile nodes, TCP degrades its performance. Further, it lacks certain protection mechanisms from internal and external malicious nodes. In this paper, a security enhanced and adaptive TCP, namely SA-TCP, has been proposed for wireless ad hoc networks. SA-TCP uses network layer information to detect various types of packet losses and adjusts the value of congestion window dynamically according to the conditions of the dynamic network. It works normally to collect the samples of congestion window and calculates the mean from these samples to set the value of future congestion window. SA-TCP also adjusts the value of congestion window limit according to network conditions. In order to make SA-TCP suitable in highly vulnerable wireless ad hoc networks, a less complex identity-based public key cryptography has been integrated with the proposed protocol. The three-way handshaking process of SA-TCP is made secure by generating a secret session key on-fly between source-destination. Simulation results show that SA-TCP gives higher throughput compared to the popular New Reno and ATCP in different wireless ad hoc network scenarios.
Enhanced Broadcasting and Code Assignment in Mobile Ad Hoc Networks
Jinfang Zhang,Zbigniew Dziong,Francois Gagnon,Michel Kadoch
Journal of Systemics, Cybernetics and Informatics , 2008,
Abstract: A CDMA-based mobile Ad Hoc networks face two main design challenges. One is to periodically update connectivity information, namely, neighboring nodes and the codes used by neighboring nodes. The other is to guarantee that there is no code collision in two hops' distance. This paper proposes an enhanced time-spread broadcasting schedule for connectivity information update. Based on the connectivity information, a code assignment and potential code collision resolution scheme to solve hidden/exposed nodes problem is proposed. Simulation results demonstrate the efficiency and effectiveness of the proposed schemes.
An Enhanced Transmission Power Controlled MAC Protocol for Ad Hoc Networks
P.Sivanesan,Dr.S.Thangavel
International Journal on Computer Science and Engineering , 2011,
Abstract: In mobile ad hoc networks (MANETs), every node overhears every data transmission occurring in its vicinity and thus consumes energy unnecessarily. Although lots of research has been done on energy efficiency remains it is an open problem. However, transmission power control (TPC) has been extensively used not only to save energy, but also to improve the network throughput. In this paper, we propose an enhanced transmission power controlled protocol, ETPMAC, which can improve the network throughput significantly using a single channel and a single transceiver. ETPMAC can enable several concurrent transmissions without interfering with each other by controlling the transmission power. Moreover, it does not introduce any additional control overhead. We show by simulation that ETPMAC can improve the network throughput by up to 71% compared to IEEE 802.11 in a random topology.
ENHANCED RELIABLE TCP FOR CONGESTION CONTROL WITH CORRUPTION CONTROL IN MOBILE AD HOC NETWORKS  [cached]
Poonam Tomar,Shweta Yadav
Journal of Global Research in Computer Science , 2012,
Abstract: Ad hoc networks are mobile networks that can be formed spontaneously without the requirement of a centralized access point or an existing infrastructure. There are several unique characteristics of an Ad hoc network that differentiates it from other classes of networks. Most of the TCP variants have been designed in the context of wired networks and the reason of poor performance of TCP is due to ignoring the properties of wireless Ad hoc networks. For TCP to adapt itself to Ad hoc environments, several improvements have been proposed that helps to differentiate between different types of losses. This is because in mobile Ad hoc network losses are not always due to congestion .In this paper we are presenting a new enhanced mechanism for TCP corruption control. This scheme will use the congestion control mechanism while the network is congested and vary the congestion window to hold the packet sending rate while the wireless link is corrupted Further the drop rate is calculated. A comparative study of Enhanced Reliable TCP is carried out with other TCP variants like TCP Tahoe and TCP New Reno on the basis of various parameters. ERTCP is implemented and all the implementations and simulations are performed on QualNet 5.0 simulator.
Enhanced DSR Protocol with Multicost Algorithm in Wireless Ad hoc Networks
D.LOGANATHAN,P.RAMAMOORTHY
International Journal of Engineering Science and Technology , 2012,
Abstract: A Wireless ad hoc network is a collection of wireless mobile nodes that dynamically form a network connection temporarily without any support of static infrastructre. The dynamics of an ad hoc network are a challenge to protocol design because mobility of nodes leads to unstable routing, and consequently flows encounter fluctuations in resource availability on various paths during the lifetime of a session. There are several routing protocols like DSDV, AODV, DSR, OLSR, Etc… which have been proposed for providing communicationamong all the nodes in the network. This paper presents the comparision performance of DSR protocol with enhancecd DSR protocol which is combined with the multicost algorithm in DSR. In the modified approach of DSR,to enhance the performance of Packet Delivery Ratio and throughput of the wireless ad hoc networks.
Enhanced Partial Dominant Pruning (EPDP) Based Broadcasting in Ad hoc Wireless Networks  [cached]
Ashikur Rahman,Md. Endadul Hoque,Farzana Rahman,Sabuj Kumar Kundu
Journal of Networks , 2009, DOI: 10.4304/jnw.4.9.895-904
Abstract: In many applications of ad-hoc wireless networks, one often has to broadcast the same message to all nodes. The major goal of any broadcasting algorithm is to minimize the number of retransmissions, i.e., to accomplish the goal with the minimum amount of traffic in the network. In addition to reducing the bandwidth expense needed to convey the message to all the nodes, this objective will try to minimize the total amount of energy spent by the nodes on this communal task. This is of paramount importance in sensor networks, which are often built of disposable nodes, whose life-time is directly determined by the efficiency of their power management scheme. In this paper, we present a heuristic broadcast algorithm dubbed EPDP, for Enhanced Partial Dominant Pruning, and demonstrate its superiority, in terms of the total number of retransmissions, over other solutions addressing the same issue.
Enhanced Antenna Position Implementation Over Vehicular Ad Hoc Network (VNET) In 3D Space  [PDF]
Soumen Kanrar,Mohammad Siraj
International Journal of Wireless & Mobile Networks , 2010,
Abstract: The technology related to networking moves wired connection to wireless connection. The basic problem concern in the wireless domain, random packet loss for the end to end connection. Inthis paper we show the performance and the impact of the packet loss and delay, by the bit error rate throughput etc with respect to the real world scenario vehicular ad hoc network in 3-dimension space(VANET in 3D). Over the years software development has responded to the increasing growth of wireless connectivity in developing network enabled software. In this paper we consider the real world physicalproblem in three dimensional wireless domain and map the problem to analytical problem . In this paper we simulate that analytic problem with respect to real world scenario by using enhanced antenna position system (EAPS) mounted over the mobile node in 3D space. In this paper we convert the real world problem into lab oriented problem by using the EAPS –system and shown the performance inwireless domain in 3 dimensional space.
Enhanced Antenna Position Implementation Over Vehicular Ad Hoc Network (VNET) In 3D Space  [PDF]
Soumen Kanrar,Mohammad Siraj
Computer Science , 2011,
Abstract: The technology related to networking moves wired connection to wireless connection.The basic problem concern in the wireless domain, random packet loss for the end to end connection. In this paper we show the performance and the impact of the packet loss and delay, by the bit error rate throughput etc with respect to the real world scenario vehicular ad hoc network in 3-dimension space (VANET in 3D). Over the years software development has responded to the increasing growth of wireless connectivity in developing network enabled software. In this paper we consider the real world physical problem in three dimensional wireless domain and map the problem to analytical problem . In this paper we simulate that analytic problem with respect to real world scenario by using enhanced antenna position system (EAPS) mounted over the mobile node in 3D space. In this paper we convert the real world problem into lab oriented problem by using the EAPS -system and shown the performance in wireless domain in 3 dimensional space.
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