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The smart grid is an emerging technology that integrates power infrastructures with information technologies to enable intelligent energy managements. As one of the most important facilities of power infrastructures, electrical substations undertake responsibilities of energy transmissions and distributions by operating interconnected electrical devices in a coordinated manner. Accordingly, it imposes a great challenge on information security, since any falsifications may trigger mal-operations, and result in damages to power usage. In this paper, we aim at authentication and integrity protections in substation automation systems (SAS), by an experimental approach on a small scale SAS prototype, in which messages are transmitted with commonly-used data origin authentication schemes, such as RSA, Message Authentication Code, and One-Time Signature. Through experimental results, we find that, current security solutions cannot be applied directly into the SAS due to insufficient performance considerations in response to application constraints, including limited device computation capabilities, stringent timing requirements and high data sampling rates. Moreover, intrinsic limitations of security schemes, such as complicated computations, shorter key valid time and limited key supplies, can easily be hijacked by malicious attackers, to undermine message deliveries, thus becoming security vulnerabilities. Our experimental results demonstrate guidelines in design of novel security schemes for the smart grid. [ABSTRACT FROM AUTHOR]

Navigation with wireless sensor networks (WSNs) is the key to provide an effective path for the mobile node. Without any location information, the path planning algorithm generates a big challenge. Many algorithms provided efficient paths based on tracking sensor nodes which forms a competitive method. However, most previous works have overlooked the distance cost of the path. In this paper, the problem is how to obtain a path with minimum distance cost and effectively organize the network to ensure the availability of this path. We first present a distributed algorithm to construct a path planning infrastructure by uniting the neighbors' information of each sensor node into an improved connected dominating set. Then, a path planning algorithm is proposed which could produce a path with its length at most c times the shortest Euclidean length from initial position to destination. We prove that the distributed algorithm has low time and message complexity and c is no more than a constant. Under different deployed environments, extensive simulations evaluate the effectiveness of our work. The results show that factor c is within the upper bound proved in this paper and our distributed algorithm achieves a smaller infrastructure size. [ABSTRACT FROM AUTHOR]

Optimal sensor placement (OSP) technique plays a key role in the structural health monitoring (SHM) of large-scale civil infrastructures. This paper outlines an overview of current research and development in the field of OSP problems in a perspective of both researchers and engineers. The paper begins with a definition of the model of sensor placement and provides the basic issues covering relevant methodologies. The primary evaluation criteria and main sensor placement methods are then discussed in details. Following that, the linkage between several influential sensor placement methods is described. Finally, existing problems and promising research efforts in the OSP problem of civil SHM are discussed. [ABSTRACT FROM AUTHOR]

Indoor localization in smoke conditions is one of the EU GUARDIANS project goals. When smoke density grows, optical sensors such as laser range finders and cameras cease to be efficient. Zigbee sensor networks provide an interesting approach due to the fact that radiofrequency signals are propagated easily in such conditions. Moreover, they permit having an alternative communication infrastructure to the emergency brigades, allowing also the implementation of localization algorithms for the mobile sensors, actuators, and firefighters. The overall localization method (i.e., ARIEL) aims to acquire the nodes position in real time during an intervention, using different sensor inputs such as laser, sonar, Zigbee, and Wifi signals. Moreover, a fine grained localization algorithm has been implemented to localize special points of interest such as emergency doors and fire extinguishers, using a Zigbee programmable high-intensity LED panel. This paper focuses on the Zigbee fingerprinting localization method used to obtain the position of the mobile sensors and actuators by training a database of radio signals for each scenario. Once this is done the proposed recognition method runs in a quite stable and accurate manner without needing any sophisticated hardware. Results compare the procedure with others such as KNN, and neural networks, demonstrating the feasibility of the method for a real emergency intervention. [ABSTRACT FROM AUTHOR]

Ad hoc networks are built on the basis of a communication without infrastructure and major investigations have focused on the routing and auto configuration problems. However, there is a little progress in solving the secure auto configuration problems in mobile ad hoc networks (MANETs), which has led to the proliferation of threats given the vulnerabilities of MANETs. It is clear that ad hoc networks have no centralized mechanism for defense against threats, such as a firewall, an intrusion detection system, or a proxy. Therefore, it is necessary that the defense of interests of each of the ad hoc components is the responsibility of each member node. This paper shows the most common threats to ad hoc networks and reviews several proposals that attempt to minimize some of these threats, showing their protection ability and vulnerabilities in light of the threats that might arise. [ABSTRACT FROM AUTHOR]

Wireless sensor network (WSN) application development is not an easy task due to its resource constrained nature and vast feature rich application space. Several abstractions are harnessed to ease out the difficult WSN application development. In this paper, three levels of abstractions are classified fromthe existing literature: node, network, and infrastructure abstractions. Since the node and network abstractions are already a well-studied area, the infrastructure abstraction is surveyed in detail to complete knowledge. Technology interoperability, service discovery, metadata support, and processing support are found as basic requirements for infrastructure abstraction. Problematic security and quality of service topics are discussed and the open research questions of ontology, service discovery, distributed processing, and performance metrics are defined. Finally, a distributed middleware design is presented as a possible solution for the key open research question: how to utilize capabilities of the abstracted technologies. [ABSTRACT FROM AUTHOR]

In the twenty-first century, the impact of wireless and ubiquitous technologies is changing the way people perceive and interact with the physical world. These communication paradigms promise to change and redefine, in a reasonably short period of time, themost common way of our everyday living. The continuous advances in the field of Wireless Sensor Networks and their direct application in Smart Spaces are clear examples of it. However, in order for this kind of new generation infrastructures to have a large-scale dissemination, there are still some open issues to tackle. In this way, this paper presents nSOM, a service-oriented framework based on sensor network design that provides internet working services with the Internet cloud. This light weight middleware architecture implements an agent-based virtual sensor service approach which is a compact semantic knowledge management scheme based on a dynamic composition model. [ABSTRACT FROM AUTHOR]

Critical infrastructure monitoring applications are rapidly increasing. Application requirements include reliable data transfer, energy efficiency, and long deployment lifetime. These applications must also be able to operate in an extremely low-cost communication environment in order to be attractive to potential users. A low rate wireless personal area network can help control and manage the operations of such applications. In this paper, we present a medium access control (MAC) protocol for low-energy critical infrastructure monitoring (LECIM) applications. The proposed MAC protocol is based on a framed slotted aloha multiple access schemes. For downlink communication, we use a wakeup radio approach to avoid complex bookkeeping associated with the traditional MAC protocols. Analytical expressions for power consumption and delay are derived to analyze and compare the performance of our proposed protocol with the existing well-known T-MAC, B-MAC, X-MAC, ZigBee, and Wise MAC protocols. It is shown that our proposed protocol outperforms all the other protocols in terms of power consumption and delay. [ABSTRACT FROM AUTHOR]

The concept of Intelligent Transportation Systems (ITSs) has been recently introduced to define modern embedded systems with enhanced digital connectivity, combining people, vehicles, and public infrastructure. The smart transducer concept, on the other hand, has been established by the IEEE 1451 standard to simplify the scalability of networked electronic equipments. The synergy of both concepts will establish a new paradigm in the near future of the ITS area. The purpose of this paper is to analyze the integration of electronic equipments into intelligent road-traffic management systems by using the smart transducer concept. An automated video processing sensor for road-traffic monitoring applications is integrated into an ITS network as a case study. The impact of the IEEE 1451 standard in the development and performance of ITS equipments is analyzed through its application to this video-based system, commercialized under the name VisioWay. [ABSTRACT FROM AUTHOR]

Vehicular sensors capture a large amount of data, and a routing algorithm is needed to effectively propagate the data in vehicular sensor network (VSN). The existing routing algorithms in vehicular ad hoc network (VANET) can not be transplanted to VSN directly. After analyzing the mobility of vehicles, we find that the delivery time of vehicle to vehicle (V2V) or vehicle to infrastructure (V2I) is very short especially when a deliverer is at a corner or crossroad and tries to deliver data to its left/right direction. Using existing routing algorithms in VANET will cause the big amount of data to stuck at corners or crossroads and to be transmitted back and forth with very few data packets being delivered. It is very time consuming and computation consuming. In this paper, we propose a data delivery algorithm called distribution-based data delivery to handle the above-mentioned corner problem with the help of some vehicular sensors like accelerometer. Evaluations show that the time cost of data delivery at corners is saved for at least 30% by our algorithm comparing to other routing algorithms like VADD in VANET. [ABSTRACT FROM AUTHOR]

Recently, wireless sensor networks (WSNs) have gained great attention from the research community for various smart grid applications, including advanced metering infrastructure (AMI), power outage detection, distribution automation, towers and poles monitoring, line fault diagnostics, power fraud detection, and underground cable system monitoring. However, multipath, fading, environmental noise, and obstructions in harsh smart grid environments make reliable communication a challenging task for wireless-sensor-network- (WSN-) based smart grid applications. To overcome varying link conditions in smart grid environments, sensor nodes must be capable of estimating link quality dynamically and reliably. In this paper, the performance of the state-of-the-art link-quality estimation methods is investigated for different smart power grid environments, such as outdoor substation, underground network transformer vault, and main power control room, in terms of packet delivery ratio, average number of packet retransmissions, average number of parent changes, average number of hops, and average communication delay. In addition, main smart grid characteristics and potential applications of WSNs in smart grid have been introduced along with the related technical challenges. Overall, our performance evaluations show that the link-quality estimators, called Expected Transmission Count (ETX) and four-bit, show the best performance in harsh smart grid environments. [ABSTRACT FROM AUTHOR]

The smart grid is an emerging technology that integrates power infrastructures with information technologies to enable intelligent energy managements. As one of the most important facilities of power infrastructures, electrical substations undertake responsibilities of energy transmissions and distributions by operating interconnected electrical devices in a coordinated manner. Accordingly, it imposes a great challenge on information security, since any falsifications may trigger mal-operations, and result in damages to power usage. In this paper, we aim at authentication and integrity protections in substation automation systems (SAS), by an experimental approach on a small scale SAS prototype, in which messages are transmitted with commonly-used data origin authentication schemes, such as RSA, Message Authentication Code, and One-Time Signature. Through experimental results, we find that, current security solutions cannot be applied directly into the SAS due to insufficient performance considerations in response to application constraints, including limited device computation capabilities, stringent timing requirements and high data sampling rates. Moreover, intrinsic limitations of security schemes, such as complicated computations, shorter key valid time and limited key supplies, can easily be hijacked by malicious attackers, to undermine message deliveries, thus becoming security vulnerabilities. Our experimental results demonstrate guidelines in design of novel security schemes for the smart grid. [ABSTRACT FROM AUTHOR]

Data dissemination is the fundamental operation in vehicular ad hoc networks (VANETs); for example, after an accident or congestion is detected by the corresponding sensors mounted on the vehicles, an alert message should be swiftly disseminated to the vehicles moving towards the affected areas. However, the unique characteristics of VANETs, such as high mobility of vehicle nodes, intermittent connectivity, and rapidly dynamic topology, make data dissemination over them extremely challenging. Motivated by the fact that there are large amounts of roadside parked vehicles in urban areas, this paper proposes a parking-based data dissemination scheme for VANETs. Data to be disseminated are buffered at the roadside parked vehicle, which continuously provides data dissemination services for the vehicles passing by. We analyze the challenging issues in achieving parking-based data dissemination and provide possible solution for each issue. Theoretical results illustrate the effectiveness of our approach, and simulation results based on a real city map and realistic traffic situations show that the proposed data dissemination paradigm achieves a higher delivery ratio with lower network load and reasonable delivery delay. [ABSTRACT FROM AUTHOR]