The Internet of Things (IoT) vision is to connect uniquely identifiable devices that surround us to the Internet, which is best described through ontologies. Thereby, new emerging technologies such... Show More

The Internet of Things (IoT) vision is to connect uniquely identifiable devices that surround us to the Internet, which is best described through ontologies. Thereby, new emerging technologies such as wireless sensor networks (WSN) are recognized as an essential enabling component of the IoT today. Hence, given the increasing interest to provide linked sensor data through the Web either following the Semantic Web Enablement (SWE) standard or the Linked Data approach, there is a need to also explore those data for potential hidden knowledge through data mining techniques utilized by a domain ontology. Following that rationale, a new lightweight IoT architecture SEMDPA has been developed. It supports linking sensors and other devices, as well as people via a single web by mean of a device-person-activity (DPA) crossroad ontology. The architecture is validated by mean of three rich-in-semantic services: contextual data mining over WSN, semantic WSN web enablement, and Linked WSN data. SEMDPA could be easily extensible to capture semantics of input sensor data from other domains as well.

Security in mobile wireless sensor networks is a big challenge because it adds more complexity to the network in addition to the problems of mobility and the limited sensor node resources. Even with... Show More

Security in mobile wireless sensor networks is a big challenge because it adds more complexity to the network in addition to the problems of mobility and the limited sensor node resources. Even with authentication and encryption mechanisms, an attacker can compromise nodes and get all the keying materials. Therefore, an intrusion detection system is necessary to detect and defend against the insider attackers. Currently, there is no intrusion detection system applied to IPv6-based mobile wireless sensor networks. This paper is mainly interested in detecting the selective forwarding and clone attacks because they are considered among the most dangerous attackers. In this work, the authors design, implement, and evaluate a novel intrusion detection system for mobile wireless sensor networks based on IPv6 routing protocol for low power and lossy networks. The new intrusion detection system can be extended to other attacks such as wormhole and sybil attacks. The simulations results show that the detection probability is 100% for selective attackers under some cases.

As the energy efficiency remains a key issue in wireless sensor networks, duty-cycled mechanisms acquired much interest due to their ability to reduce energy consumption by allowing sensor nodes to... Show More

As the energy efficiency remains a key issue in wireless sensor networks, duty-cycled mechanisms acquired much interest due to their ability to reduce energy consumption by allowing sensor nodes to switch to the sleeping state whenever possible. The challenging task is to authorize a sensor node to adopt a duty-cycle mode without inflicting any negative impact on the performance of the network. A context-aware paradigm allows sensors to adapt their functional behavior according to the context in order to enhance network performances. In this context, the authors propose an enhanced version the Efficient Context-Aware Multi-hop Broadcasting (E-ECAB) protocol, which combines the advantages of context awareness by considering a multi criteria and duty-cycle technique in order to optimize resources usage and satisfy the application requirements. Simulation results show that E-ECAB achieves a significant improvement in term of throughput and end-to-end delay without sacrificing energy efficiency.

While existing localization approaches mainly focus on enhancing the accuracy, particular attention has recently been given to reducing the localization algorithm implementation costs. To obtain a... Show More

While existing localization approaches mainly focus on enhancing the accuracy, particular attention has recently been given to reducing the localization algorithm implementation costs. To obtain a tradeoff between location accuracy and implementation cost, recursive localization approaches are being pursued as a cost-effective alternative to the more expensive localization approaches. In the recursive approach, localization information increases progressively as new nodes compute their positions and become themselves reference nodes. A strategy is then required to control and maintain the distribution of these new reference nodes. The lack of such a strategy leads, especially in high density networks, to wasted energy, important communication overhead and even impacts the localization accuracy. In this paper, the authors propose an efficient recursive localization approach that reduces the energy consumption, the execution time, and the communication overhead, yet it increases the localization accuracy through an adequate distribution of reference nodes within the network.

Taxis have a vital role in the transportation system and Internet of Vehicles (IoV) techniques can be used to improve the fuel and time efficiencies of taxis. However, the existing work does not... Show More

Taxis have a vital role in the transportation system and Internet of Vehicles (IoV) techniques can be used to improve the fuel and time efficiencies of taxis. However, the existing work does not address the traffic congestion that may occur when a large amount of taxis gathers in certain queuing areas. This paper proposes an adaptive and hotspot-aware taxi zone queuing system to deal with the problem while still guarantees the fuel and time efficiencies. The adaptive scheme features data collection, hotspot extraction, an adaptive zone queuing protocol, and navigation services for taxi drivers. Real data were collected from Taiwan Taxi Inc., the largest taxi company in Taiwan. Queuing zone hotspots were identified through the analysis of the collected data. The hotspots represented. A navigation service was based on the proposed protocol. To verify the feasibility of the proposed system, a prototype was implemented. The experimental results demonstrated that the proposed scheme outperformed other schemes in reducing waiting time and the average number of taxis.