As new fabrication and integration technologies reduce the cost and size of micro-sensors and wireless interfaces, it becomes feasible to deploy densely distributed wireless networks of sensors and actuators. These systems promise to revolutionize biological, earth, and environmental monitoring applications, providing data at granularities unrealizable by other means. In addition to the challenges of miniaturization, new system architectures and new network algorithms must be developed to transform the vast quantity of raw sensor data into a manageable stream of high-level data. To address this, we propose a tiered system architecture in which data collected at numerous, inexpensive sensor nodes is filtered by local processing on its way through to larger, more capable and more expensive nodes.We briefly describe Habitat monitoring as our motivating application and introduce initial system building blocks designed to support this application. The remainder of the paper presents details of our experimental platform.

Habitat monitoring: Application driver for wireless communications technology

The Man-In-The-Middle (MITM) attack is one of the most well known attacks in computer security, representing one of the biggest concerns for security professionals. MITM targets the actual data that flows between endpoints, and the confidentiality and integrity of the data itself. In this paper, we extensively review the literature on MITM to analyse and categorize the scope of MITM attacks, considering both a reference model, such as the open systems interconnection (OSI) model, as well as two specific widely used network technologies, i.e., GSM and UMTS. In particular, we classify MITM attacks based on several parameters, like location of an attacker in the network, nature of a communication channel, and impersonation techniques. Based on an impersonation techniques classification, we then provide execution steps for each MITM class. We survey existing countermeasures and discuss the comparison among them. Finally, based on our analysis, we propose a categorisation of MITM prevention mechanisms, and we identify some possible directions for future research.

A Survey of Man In The Middle Attacks

Safety-critical applications in cooperative vehicular networks require authentication of nodes and messages. Yet, privacy of individual vehicles and drivers must be maintained. Pseudonymity can satisfy both security and privacy requirements. Thus, a large body of work emerged in recent years, proposing pseudonym solutions tailored to vehicular networks. In this survey, we detail the challenges and requirements for such pseudonym mechanisms, propose an abstract pseudonym lifecycle, and give an extensive overview and categorization of the state of the art in this research area. Specifically, this survey covers pseudonym schemes based on public key and identity-based cryptography, group signatures and symmetric authentication. We compare the different approaches, give an overview of the current state of standardization, and identify open research challenges.

Pseudonym Schemes in Vehicular Networks: A Survey

Vehicular ad hoc networks (VANETs) have stimulated interest in both academic and industry settings because, once deployed, they would bring a new driving experience to drivers. However, communicating in an open-access environment makes security and privacy issues a real challenge, which may affect the large-scale deployment of VANETs. Researchers have proposed many solutions to these issues. We start this paper by providing background information of VANETs and classifying security threats that challenge VANETs. After clarifying the requirements that the proposed solutions to security and privacy problems in VANETs should meet, on the one hand, we present the general secure process and point out authentication methods involved in these processes. Detailed survey of these authentication algorithms followed by discussions comes afterward. On the other hand, privacy preserving methods are reviewed, and the tradeoff between security and privacy is discussed. Finally, we provide an outlook on how to detect and revoke malicious nodes more efficiently and challenges that have yet been solved.

A Security and Privacy Review of VANETs

Vehicular ad hoc networks (VANETs) have attracted a lot of attention in the research community in recent years due to their promising applications. VANETs help improve traffic safety and efficiency. Each vehicle can exchange information to inform other vehicles about the current status of the traffic flow or a dangerous situation such as an accident. Road safety and traffic management applications require a reliable communication scheme with minimal transmission collisions, which thus increase the need for an efficient medium access control (MAC) protocol. However, the design of the MAC in a vehicular network is a challenging task due to the high speed of the nodes, the frequent changes in topology, the lack of an infrastructure, and various QoS requirements. Recently, several time-division multiple-access (TDMA)-based MAC protocols have been proposed for VANETs in an attempt to ensure that all the vehicles have enough time to send safety messages without collisions and to reduce the end-to-end delay and the packet loss ratio. In this paper, we identify the reasons for using the collision-free MAC paradigm in VANETs. We then present a novel topology-based classification, and we provide an overview of TDMA-based MAC protocols that have been proposed for VANETs. We focus on the characteristics of these protocols, as well as on their benefits and limitations. Finally, we give a qualitative comparison, and we discuss some open issues that need to be tackled in future studies in order to improve the performance of TDMA-based MAC protocols for vehicle-to-vehicle communications.

/pdf/tdma-based-mac-protocols-for-vehicular-ad-hoc-networks-a-3cu4otstng.pdf

TDMA-Based MAC Protocols for Vehicular Ad Hoc Networks: A Survey, Qualitative Analysis, and Open Research Issues

Lane changing process is an essential maneuver, however, the process is responsible for large number of collisions and traffic instability. In this work, the effectiveness of neural network for prediction of future lane change trajectory based only on the past vehicle path is presented. Existing lane change models and lane change process do not consider the uncertainties and perceptions in the human behavior that are involved in lane changing. A neural network may learn and incorporate these uncertainties to predict the lane changing trajectory in the near future more accurately. A multilayer perceptron (MLP) has been employed to train itself from existing NGSIM field data and predict the future path of a lane changing vehicle. The impact and effectiveness of the proposed technique is demonstrated. Prediction results show that an MLP is able to give the future path accurately only for discrete patches of the trajectory and not over the complete trajectory. The results confirm to the observation that a vehicle trajectory has immediate influence from its neighborhood whose information is imperative for trajectory prediction.

Prediction of Lane Change Trajectories through Neural Network

Use of discontinuities in ground planes or in micro strip lines is currently employed to improve the performance of different passive circuits. It includes size reduction of amplifiers, enhancement of filter characteristics and applications to suppress harmonics in patch antennas. This paper presents an improved method of size reduction of a micro strip antenna using Defected Micro strip Structure. It does so by introducing imperfections in the micro strip antenna on the conducting layer using a DMS designed defect. The design was simulated using IE3D Electromagnetic Simulator. The results are very encouraging as it increases the number of components in a given constant area. On the other hand, a new proposal, called defected micro strip structure (DMS), has been successfully used in reducing the size of, and can be further used as tuning technique for, rectangular patch antennas.

Size Reduction of Microstrip Patch Antenna Using Defected Microstrip Structures

Wireless sensor networks have grown rapidly with the innovation in Information Technology. Sensor nodes are distributed and deployed over the area for gathering requisite information. Sensor nodes possess a negative characteristic of limited energy which pulls back the network from exploiting its peak capabilities. Hence, it is necessary to gather and transfer the information in an optimized way which reduces the energy dissipation. Ant Colony Optimization (ACO) is being widely used in optimizing the network routing protocols. Ant Based Routing can play a significant role in the enhancement of network life time. In this paper, Intercluster Ant Colony Optimization algorithm (IC-ACO) has been proposed that relies upon ACO algorithm for routing of data packets in the network and an attempt has been made to minimize the efforts wasted in transferring the redundant data sent by the sensors which lie in the close proximity of each other in a densely deployed network. The IC-ACO algorithm was studied by simulation for various network scenarios. The results depict the lead of IC-ACO as compared to LEACH protocol by indicating higher energy efficiency, prolonged network lifetime, enhanced stability period, and the elevated amount of data packets in a densely deployed wireless sensor network.

Intercluster Ant Colony Optimization Algorithm for Wireless Sensor Network in Dense Environment

This paper presents two-stage detectors for spectrum sensing in cognitive radio networks. The first stage consists of multiple energy detectors, where each energy detector (ED) has a single antenna with fixed threshold for making a local binary decision. If required, the second stage comprised of ED with adaptive double threshold is invoked. The detection performance of the proposed scheme is compared with a cyclostationary-based sensing method and adaptive spectrum sensing scheme. The numerical results show that the proposed scheme improves detection performance and outperforms the cyclostationary-based sensing method and adaptive spectrum sensing by 12.3% and 14.4% at signal-to-noise ratio (SNR) setting of as low as -8 dB, respectively. Performance was also measured in terms of sensing time and scheme has smaller sensing time than cyclostationary detection and adaptive spectrum sensing scheme in the order of 4.3 and 0.1 ms at -20-dB SNR, respectively. Furthermore, the scheme was analyzed in conjunction with cooperative spectrum sensing (CSS), where each cognitive radio (CR) user used two-stage spectrum sensing detectors for local detection and sent detection decisions to the fusion center to give the final decision based on hard decision OR rule. It is further found that the proposed two-stage spectrum sensing scheme with CSS achieves spectrum detection performance in the order of 0.9 for an SNR value of as low as -19 dB as the number of CR users (K) is 10.

Cooperative Spectrum Sensing Based on Two-Stage Detectors With Multiple Energy Detectors and Adaptive Double Threshold in Cognitive Radio Networks

Modern computer system rely more and more on -- chip communication protocol to exchange data. System-on-chip (SoC) designs use bus protocols for high performance data transfer among the Intellectual Propert (IP) cores. These protocols incorporate advanced features such as pipelining, burst and split transfers. In this paper, we describe a case study for different AMBA SOC bus protocol and their performance comparison: the Advanced Micro-controller Bus Architecture (AMBA) protocol from ARM. It starts ith a brief introduction AMBA 2.0 protocol, AMBA 3.0 protocol and AMBA 4.0 protocol, and concludes with a discussion related to a comparison performance analysis of all three AMBA bus protocol.

Geetam Singh Tomar

Papers

Prediction of Lane Change Trajectories through Neural Network

Size Reduction of Microstrip Patch Antenna Using Defected Microstrip Structures

Intercluster Ant Colony Optimization Algorithm for Wireless Sensor Network in Dense Environment

Cooperative Spectrum Sensing Based on Two-Stage Detectors With Multiple Energy Detectors and Adaptive Double Threshold in Cognitive Radio Networks

Performance Comparison of AMBA Bus-Based System-On-Chip Communication Protocol