Table of Contents

Abstract: As the usage and development of wireless sensor networks increases, problems related to these networks are becoming apparent. Dynamic deployment is one of the main topics that directly affects the performance of the wireless sensor networks. In this paper, biogeography-based optimization is applied to the dynamic deployment of static and mobile sensor networks to achieve better performance by trying to increase the coverage area of the network. A binary detection model is considered to obtain realistic results while computing the effectively covered area. Performance of the algorithm is compared with that of the artificial bee colony algorithm, Homo-H-VFCPSO and stud genetic algorithm that are also population-based optimization algorithms. Results show biogeography-based optimization can be preferable in the dynamic deployment of wireless sensor networks.

Abstract: In a residential or nursing home environment, using ZigBee/802.15.4 wireless network specifically to collect and gather various types of personal health data proves to be a feasible choice. The Continua Guidelines has defined both the sensor-LAN IF (sensor Local Area Network Interface) PHD (Personal Health Device) and PAN IF (Personal Area Network Interface) PHD, but only a Continua certified sensor-LAN IF PHD with Zigbee HC (Health Care) profile can connect with Continua AHD (Application Hosting Device) through Zigbee/802.15.4 network and allows data communicating between AHD and PHDs. In this paper, we present a distributed Continua AHD system design that divides the AHD device containing Continua PAN IF into Continua AHD Host and Continua AHD Gateway with communication through ZigBee/802.15.4 network. Under this structure, a Continua PHD connects with a Continua AHD Host through Continua AHD Gateway within ZigBee/802.15.4 network. One immediate advantage of the proposed system is that both of the Continua sensor-LAN IF and PAN IF PHDs can connect with Continua AHD (Host) through ZigBee/802.15.4 network. To further address the QoS (Quality of Service) issue for Continua PAN IF message transmission in a ZigBee network, we present a software approach to automatically determine the types of packet transmitted and execute Continua QoS control. Together with the QoS mechanism in the enhanced ZigBee MAC Layer, this approach realizes a complete Continua QoS control mechanism for the distributed AHD system.

Abstract: In this paper, we present a novel low power medium access control protocol for wireless sensor networks (WSNs). The proposed protocol, EP-MAC (Efficient MAC with Parallel Transmission) achieves high energy efficiency and high packet delivery ratio under different traffic load. EP-MAC protocol is basically based on the Time Division Multiple Access (TDMA) approach. The power of Carrier Sense Multiple Access (CSMA) is used in order to offset the fundamental problems that the stand-alone TDMA method suffers from, i.e., problems such as lack of scalability, adaptability to varying situations, etc. The novel idea behind the EP-MAC is that it uses the parallel transmission concept with the TDMA link scheduling. EP-MAC uses the methods for the transmission power adjustment, i.e., uses the minimum level power necessary to reach the intended neighbor within a specified bit error rate [BER] target. This reduces energy consumption, as well as further enhances the scope of parallel transmission of the protocol. The simulation studies support the theoretical results, and validate the efficiency of our proposed EP-MAC protocol.

Abstract: While traditional wired communication technologies have played a crucial role in industrial monitoring and control networks over the past few decades, they are increasingly proving to be inadequate to meet the highly dynamic and stringent demands of today’s industrial applications, primarily due to the very rigid nature of wired infrastructures. Wireless technology, however, through its increased pervasiveness, has the potential to revolutionize the industry, not only by mitigating the problems faced by wired solutions, but also by introducing a completely new class of applications. While present day wireless technologies made some preliminary inroads in the monitoring domain, they still have severe limitations especially when real-time, reliable distributed control operations are concerned. This article provides the reader with an overview of existing wireless technologies commonly used in the monitoring and control industry. It highlights the pros and cons of each technology and assesses the degree to which each technology is able to meet the stringent demands of industrial monitoring and control networks. Additionally, it summarizes mechanisms proposed by academia, especially serving critical applications by addressing the real-time and reliability requirements of industrial process automation. The article also describes certain key research problems from the physical layer communication for sensor networks and the wireless networking perspective that have yet to be addressed to allow the successful use of wireless technologies in industrial monitoring and control networks.

Abstract: In wireless sensor networks, replica node attacks are very dangerous because the attacker can compromise a single node and generate as many replicas of the compromised node as he wants, and then exploit these replicas to disrupt the normal operations of sensor networks. Several schemes have been proposed to detect replica node attacks in sensor networks. Although these schemes are capable of detecting replicas that are widely spread in the network, they will likely fail to detect replica cluster attacks in which replicas form a cluster in a small region. These attacks are also harmful because the attacker can leverage a replica cluster to harmfully impact on the much of the network. To defend against replica cluster attacks, we propose an efficient and effective replica cluster detection scheme using the Sequential Hypothesis Testing. We evaluate our proposed scheme through analysis and simulation. The evaluation results demonstrate that it accomplishes robust replica cluster detection capability.