Ram Shringar Raw

T-MQM: Testbed-Based Multi-Metric Quality Measurement of Sensor Deployment for Precision Agriculture—A Case Study

Efficient sensor deployment is one of the primary requirements of the precision agriculture use case of wireless sensor networks (WSNs) to provide qualitative and optimal coverage and connectivity. The application-based performance variations of the geometrical-model-based sensor deployment patterns restrict the generalization of a specific deployment pattern for all applications. Furthermore, single or double metrics-based evaluation of the deployment patterns focusing on theoretical or simulation aspects can be attributed to the difference in performance of real applications and the reported performance in the literature. In this context, this paper proposes a testbed-based multi-metric quality measurement of sensor deployment for the precision agriculture use case of WSNs. Specifically, seven metrics are derived for the qualitative measurement of sensor deployment patterns for precision agriculture. The seven metrics are quantified for four sensor deployment patterns to measure the quality of coverage and connectivity. Analytical- and simulation-based evaluations of the measurements are validated through testbed experiment-based evaluations which are carried out in “INDRIYA” WSNs testbed. Toward realistic research impact, the investigative evaluation of the geometrical-model-based deployment patterns presented in this paper could be useful for practitioners and researchers in developing performance guaranteed applications for precision agriculture and novel coverage and connectivity models for deployment patterns.

Analytical Evaluation of Directional-Location Aided Routing Protocol for VANETs

Vehicular Ad-hoc Networks (VANETs) are now considered as a way to realize active safety, by providing the position information of each other or the possible danger warning by wireless vehicular communications. Multi-hop data delivery in VANETs is a challenging task, since it encounters rapid changes in network topology and frequent fragmentation in the network. Because of these characteristics, routing algorithms based on greedy forwarding are known to be very suitable for VANETs. The design and implementation of efficient and scalable routing protocols for VANETs is a challenging task due to high dynamics and mobility constraints. In this paper, we have worked on a routing protocol over VANETs to efficiently broadcast the information for the sake of active safety applications, such as the positions and the directions of the vehicles. Therefore, we have explained a position-based routing protocol called directional-location aided routing (D-LAR) with (1) location-aided routing utilizes location information using GPS to limit the area for discovering a new route to a smaller request zone and (2) directional routing having direction closest to the line drawn between source and destination. D-LAR protocol is a greedy based approach to forward packet to the node present in request zone part of sender’s transmission range as a most suitable next-hop node. Further, we have justified the feasibility of D-LAR routing protocol for VANETs. Through analytical analysis we have also given the relationship among the average number of hop counts, link lifetime, and path throughput metrics for the protocol. Finally, simulation results show that the proposed formulation can be used to evaluate path throughput accurately in the network.

Geometrical Localization Algorithm for Three Dimensional Wireless Sensor Networks

The issue of localization has been addressed in many research areas such as vehicle navigation systems, virtual reality systems, user localization in wireless sensor networks (WSNs). In this paper, we have proposed an efficient range-free localization algorithm: Geometrical Localization Algorithm (GLA) for large scale three dimensional WSNs. GLA uses moving anchors to localize static sensors. GLA consists of beacon message selection, circular cross section selection. Three beacon messages are used to compute the center of circular cross section using vector method and perpendicular bisector method. The static sensors are localized with help of the center of circular cross section and geometrical rules for sphere. GLA is simulated in SINALGO software and results have been compared with existing methods namely chord selection and point localization. GLA outperforms both the compared methods in terms of average localization time and beacon overhead.

Detection of Web-Based Attacks by Analyzing Web Server Log Files

In today’s scenario, Web traffic is increasing everyday in the world and has overtaken P2P traffic. The Websites are getting hacked on daily basis. These rises in hacking activity pose a greater threat than the network attacks as they threaten to steal crucial and important information from Website. This information can be related to the users, employee, and other important data stored in applications and database linked to the Website. Increase in Web network traffic has opened new and more efficient attack vectors for the hackers and attackers to work with. Attackers take advantage of the vulnerability in traditional firewalls deployed on Website. These firewalls are not designed to protect Web applications; lots of Websites are getting attacked by malicious scripts and users. In this paper, many Web attacks are carried out on Web applications hosted on local server to analyze the log file created after the attacks. A Web application log file allows a detailed analysis of a user action. We have simulated some Web attacks using MATLAB. Results extracted from this process helps in the recognition of majority of the attacks and helps in prevention from further exploitation.

Performance Analysis of Routing Protocols for VANETs with Real Vehicular Traces

In this study, we have evaluated the performance vehicular ad hoc network (VANET) with real vehicular traces. The vehicular movements are generated with IDM_IM mobility model. This mobility model used to emulate the movement pattern of nodes, i.e., vehicles on streets defined by maps. Our objective is to provide a comparative performance analysis among various ad hoc routing protocols, i.e., LAR1, AODV, and DSR protocols. The simulation work has been conducted using the Glomosim 2.03 simulator. The results show that LAR1 protocol achieves maximum packet delivery ratio is 100 % in the sparsely populated network. The results show that LAR1 outperforms DSR and AODV in terms of packet delivery ratio.

A New Approximate Closed-Form Distribution and Performance Analysis of a Composite Weibull/Log-Normal Fading Channel

The presence of both the fading and shadowing effects (also called composite multipath/shadowed fading) is often encountered in a realistic radio propagation scenario, thus, making it necessary to consider the simultaneous effect of fading and shadowing on the received signal. The multipath effect is captured using models such as Rician, Nakagami-m, Weibull distribution and shadowing effect is modeled using Log-normal distribution. In this paper we present the closed-form expression of composite (Weibull/log-normal shadowed) fading using the efficient tool proposed by Holtzman. Using this result, the closed-form expression of combined (time-shared) shadowed/unshadowed fading is presented. The performance measures of fading communication systems such as probability density function of signal to noise ratio, amount of fading, outage probability (Pout) and channel capacity are analyzed and expressed in closed form.

Distance and direction-based location aided multi-hop routing protocol for vehicular ad-hoc networks

Vehicular ad-hoc network VANET is an important technology for future development of intelligent transportation systems. Due to the highly-dynamic nature of vehicular nodes, network topology changes very frequently which complicate the routing of data packets. A number of routing protocols have been developed by various researchers. Hop count is a key parameter in evaluating the performance of a routing protocol. Number of hops required in directional routing protocols is more in comparison to other routing protocols. For a city vehicular traffic scenario we propose an improved direction-based location aided routing D-LAR protocol that we call distance and direction-based location aided routing DD-LAR protocol. A mathematical model for DD-LAR protocol has been developed to examine its performance on path duration and hop count metric. Simulations have been done in MATLAB and from the results, it can be seen that DD-LAR routing protocol shows significant performance improvement over D-LAR and LAR in terms of reducing the hop count and maximising the path duration.

A probabilistic analysis of border node-based MFR routing protocol for vehicular ad hoc networks

In this paper, we examined the significance of position-based routing with border-node-based forwarding for vehicular ad hoc network VANET to optimise path length between vehicles. We have mathematically evaluated the performance of border node-based forwarding method such as Border node-based MFR B-MFR. B-MFR strongly avoids the interior nodes within the transmission range for further transmitting the packets. Furthermore, we have developed a mathematical model for B-MFR to determine average number of hop counts, expected distance between source and destination, and maximum progress of the next-hop node towards the destination node using Poisson distribution for node deployment. Analytical and simulation results indicate that B-MFR can provide efficient routing in VANETs. In our work, results clearly show that using the border-nodes is an advantage to maximise the performance of routing protocol in terms of average number of hops with minimum delay. We have mathematically simulated the proposed protocol in MATLAB and compared the result with existing routing protocol MFR.

Cloud Computing in VANETs: Architecture, Taxonomy, and Challenges

ABSTRACT Cloud computing in VANETs (CC-V) has been investigated into two major themes of research including vehicular cloud computing (VCC) and vehicle using cloud (VuC). VCC is the realization of autonomous cloud among vehicles to share their abundant resources. VuC is the efficient usage of conventional cloud by on-road vehicles via a reliable Internet connection. Recently, a number of advancements have been made to address the issues and challenges in VCC and VuC. This paper qualitatively reviews CC-V with the emphasis on layered architecture, network component, taxonomy, and future challenges. Specifically, a four-layered architecture for CC-V is proposed including perception, coordination, artificial intelligence and smart application layers. Three network components of CC-V, namely, vehicle, connection, and computation are explored with their cooperative roles. A taxonomy for CC-V is presented considering major themes of research in the area including design of architecture, data dissemination, security, and applications. Related literature on each theme is critically investigated with comparative assessment of recent advances. Finally, some open research challenges are identified as future issues. The challenges are the outcome of the critical and qualitative assessment of the literature on CC-V.

Effect of traffic density patterns on the performance of routing protocols for VANETs

In this paper, we have evaluated performance of various routing protocols for Vehicular Ad Hoc Network (VANET) in different traffic patterns with real vehicular traces. The vehicular movements are based on intelligent driver model with road intersection. Our objectives is to provide a comparative analysis among various ad hoc routing protocols based on packet delivery ratio. Routing protocols are LAR1, AODV and DSR protocols. The traffic patterns categorize as sparse, moderate and dense based on the number of nodes. The results show that LAR1 protocol outperform others. The maximum packet delivery ratio obtained is 99.52% in the sparsely populated network. We have used Glomosim 2.03 and VANETMobiSim simulator for our analysis.