Eirini D. Karapistoli

An overview of the IEEE 802.15.4a Standard

This article presents the IEEE 802.15.4a standard, the first international standard that specifies a wireless physical layer to enable precision ranging. As an amendment to the popular IEEE 802.15.4-2006, the IEEE 802.15.4a-2007 standard introduces new options for the physical layer in order to support higher data rates, extended range, improved robustness against interference, and mobility, while enabling new applications based on distance information of the devices in a low-rate wireless personal area network.

Detecting Sybil attacks in wireless sensor networks using UWB ranging-based information

Development of a novel rule-based Sybil attack detection system for large-scale WSNs.Integration of UWB ranging-features with expert knowledge in the detection process.Development of a defense scheme against direct, simultaneous Sybil attacks.Derivation of a rigorous analytic framework to determine the system performance.Introduction of an accurate simulation environment to validate the detection analysis. Security is becoming a major concern for many mission-critical applications wireless sensor networks (WSNs) are envisaged to support. The inherently vulnerable characteristics of WSNs appoint them susceptible to various types of attacks. This work restrains its focus on how to defend against a particularly harmful form of attack, the Sybil attack. Sybil attacks can severely deteriorate the network performance and compromise the security by disrupting many networking protocols. This paper presents a rule-based anomaly detection system, called RADS, which monitors and timely detects Sybil attacks in large-scale WSNs. At its core, the proposed expert system relies on an ultra-wideband (UWB) ranging-based detection algorithm that operates in a distributed manner requiring no cooperation or information sharing between the sensor nodes in order to perform the anomaly detection tasks. The feasibility of the proposed approach is proven analytically, while the performance of RADS in exposing Sybil attacks is extensively assessed both mathematically and numerically. The obtained results demonstrate that RADS achieves high detection accuracy and low false alarm rate appointing it a promising ADS candidate for this class of wireless networks.

Basic guidelines for deploying Wireless Sensor Networks in agriculture

This paper provides basic guidelines for deploying Wireless Sensor Networks (WSNs) in Agriculture, and more specifically in applications requiring crop monitoring. Firstly, it reviews the main components that existing WSN applications use, namely node platforms, operating systems (OSs), power supply, etc. Based on these data, a generic guide is proposed discussing basic considerations for deploying WSNs in applications relevant to agriculture.

Wireless sensor network security visualization

Security is becoming a major concern for many mission-critical applications wireless sensor networks (WSNs) are envisaged to support. This is because WSNs are susceptible to various types of attacks or to node compromises that exploit known and unknown vulnerabilities of protocols, software and hardware, and threaten the security, integrity, authenticity, and availability of data that resides in these networked systems. While various security mechanisms have been proposed for these networks dealing with either MAC layer or network layer security issues, or key management problems, the security benefits that can be obtained from an upper visualization layer have not been adequately considered in their design. In this paper, we explore the issues and concerns surrounding the application of visual analysis for wireless sensor network security purposes. This paper focuses on several distinct advantages information visualization and visual analytics can offer in the security domain. In addition, this paper reviews security visualization tools that are available to network security analysts. Finally, it concludes by identifying challenges for this new area of research.

Performance comparison of MANET routing protocols based on real-life scenarios

In order to ensure a reliable and efficient end-to-end communication among the network nodes in a Mobile Ad Hoc Network (MANET), an appropriate routing protocol is needed. In this paper, we present an extensive simulation-based comparison of three well-known MANET routing protocols (AODV, DSDV and OLSR) evaluating their performance in three real-life scenarios. Considering various performance metrics (PDR, Delay, Average Delay, Throughput and Total Energy Consumption), we suggest the most appropriate routing protocol in every scenario.

ADLU: a novel anomaly detection and location-attribution algorithm for UWB wireless sensor networks

Wireless sensor networks (WSNs) are gaining more and more interest in the research community due to their unique characteristics. Besides energy consumption considerations, security has emerged as an equally important aspect in their network design. This is because WSNs are vulnerable to various types of attacks and to node compromises, and as such, they require security mechanisms to defend against them. An intrusion detection system (IDS) is one such solution to the problem. While several signature-based and anomaly-based detection algorithms have been proposed to date for WSNs, none of them is specifically designed for the ultra-wideband (UWB) radio technology. UWB is a key solution for wireless connectivity among inexpensive devices characterized by ultra-low power consumption and high precision ranging. Based on these principles, in this paper, we propose a novel anomaly-based detection and location-attribution algorithm for cluster-based UWB WSNs. The proposed algorithm, abbreviated as ADLU, has dedicated procedures for secure cluster formation, periodic re-clustering, and efficient cluster member monitoring. The performance of ADLU in identifying and localizing intrusions using a rule-based anomaly detection scheme is studied via simulations.

SRNET: a real-time, cross-based anomaly detection and visualization system for wireless sensor networks

Security concerns are a major deterrent in many applications wireless sensor networks are envisaged to support. To date, various security mechanisms have been proposed for these networks dealing with either Medium Access Control (MAC) layer or network layer security issues, or key management problems. Security visualization is the latest weapon that has been added in the arsenal of a security officer who is tasked with detecting network anomalies by analyzing large amounts of audit data. This paper proposes a novel security visualization system for analyzing and detecting complex patterns of sensor network attacks, called SRNET. Both selective forwarding and jamming attacks are identified through visualizing and analyzing network traffic data on multiple coordinated views, namely the multidimensional crossed view, the crossed view perspective, and the track area view. Through simulations, we demonstrate that SRNET is able to help detect and further identify the root cause of the aforementioned sensor network attacks.

MAC protocols for ultra-wideband ad hoc and sensor networking: A survey

Ultra-wideband (UWB) transmission is an emerging wireless communication technology that is gaining significant interest for future broadband wireless access. This transmission technique based mainly on the Impulse-Radio (IR) paradigm, has the potential to deliver high-speed wireless connectivity at low power and low proximity, characteristics that makes it an ideal choice for wireless sensor networks (WSNs). The distinct physical layer properties call, however, for innovative solutions at the medium access control (MAC) layer. Various MAC protocols with different objectives were proposed for these pulse-based networks. In this article, we first outline the issues related to MAC layer design relying on an IR-UWB physical layer. Then, we describe several MAC protocols emphasizing their strengths and weaknesses. Finally, we identify the cross-layer dependencies between the specified physical and the higher layers of the communication stack and investigate open research issues.

VisIoT: A threat visualisation tool for IoT systems security

Without doubt, the Internet of Things (IoT) is changing the way people and technology interact. Fuelled by recent advances in networking, communications, computation, software, and hardware technologies, IoT has stepped out of its infancy and is considered as the next breakthrough technology in transforming the Internet into a fully integrated Future Internet. However, realising a network of physical objects accessed through the Internet brings a potential threat in the shadow of the numerous benefits. The threat is “security”. Given that Wireless Sensor Networks (WSNs) leverage the potential of IoT quite efficiently, this paper faces the challenge of security attention on a particular, yet broad, context of IP-enabled WSNs. In particular, it proposes a novel threat visualisation tool for such networks, called VisIoT. VisIoT is a human-interactive visual-based anomaly detection system that is capable of monitoring and promptly detecting several devastating forms of security attacks, including wormhole attacks, and Sybil attacks. Based on a rigorous, radial visualisation design, VisIoT may expose adversaries conducting one or multiple concurrent attacks against IP-enabled WSNs. The systems visual and anomaly detection efficacy in exposing complex security threats is demonstrated through a number of simulated attack scenarios.

Location-aided medium access control for low data rate UWB wireless sensor networks

This paper presents a distributed medium access control (MAC) protocol for low data rate ultra-wideband (UWB) wireless sensor networks (WSNs), named LA-MAC. Current MAC proposal is closely coupled to the IEEE 802.15.4a physical layer and it is based on its Impulse-Radio (IR) paradigm. LA-MAC protocol amplifies its admission control mechanism with location-awareness, by exploiting the ranging capability of the UWB signals. The above property leads to accurate interference predictions and blocking assessments that each node in the network can perform locally, limiting at the same time the actions needed to be performed towards the admission phase. LA-MAC is evaluated through extensive simulations, showing a significant improvement in many critical parameters, such as throughput, admission ratio, energy consumption, and delay, under different traffic load conditions. Copyright