Attacks with Steganography in PHY and MAC Layers of 802.15.4 Protocol

International audienceWireless sensor networks are threatened by numerous attacks. Therefore, security is now becoming an important new path of research and attempts to counter these attacks. However, even if research finds solutions to counter known attacks, we show in this article that there is a threat in wireless sensor networks by using the 802.15.4 protocol. It is possible to hide data in PHY and MAC layers with steganographic techniques. In this article, we explain what steganography is, how we can use it in the layers of 802.15.4 protocol, how an attacker can do an attack and what we can do to detect this kind of threat

Improvement of LEACH for fault tolerance in sensor networks

International audienceIn wireless sensor networks, failures occur due to energy depletion, environmental hazards, hardware failure, communication link errors, etc. These failures could prevent them to accomplish their tasks. Moreover, most routing protocols are designed for ideal environment such as LEACH. Hence, if nodes fail the performance of these protocols degrade. In this context, we propose two improved versions of LEACH so that it becomes a fault-tolerant protocol. In the first version, we propose a clustered architecture for LEACH in which there are two cluster-heads in each cluster: one is primary (CHp) and the other is secondary (CHs). In the second version, we propose to use the checkpoint technique. Finally, we conducted several simulations to illustrate the performance our contribution and compared obtained results to LEACH protocol in a realistic environment

Steganography in {MAC} Layers of 802.15.4 Protocol for securing Wireless Sensor Networks

International audienceIn many applications, wireless sensor networks need to secure information. Actual researchs found efficient solutions for this kind of network, principally by using cryptography to secure the data transfer. However an encrypted information send by the network can be sufficient to prevent an attacker, who eavesdrops the network, that something important has been detected. To avoid this situation, we propose another way to secure wireless sensor networks by using steganography, specifically by hiding data in the MAC layer of the 802.15.4 protocol.We show that this solution can be an energy-efficient way with a good latency to hide data in a wireless sensor network

Checkpoint-based Fault-tolerance for LEACH Protocol

International audienceMost routing protocols designed for wireless sensor networks provide good results in ideal environments. However, their performance degrades dramatically when nodes stop working for various causes such as loss of energy, crushed by animal or climatic conditions. In this paper, we highlight the weaknesses of LEACH (Low Energy Adaptive Clustering Hierarchy) protocol by evaluating its performance. Then we propose an improved version of this protocol based on checkpoint approach that allows it to become a fault-tolerant protocol. Finally, several simulations were conducted to illustrate the benefits of our contribution

A Fault Tolerant Parallel Computing Scheme of Scalar Multiplication for Wireless Sensor Networks

International audienceIn event-driven sensor networks, when a critical event occurs, sensors should transmit messages back to base station in a secure and reliable manner. We choose Elliptic Curve Cryptography to secure the network since it offers faster computation and good security with shorter keys. In order to minimize the running time, we propose to split and distribute the computation of scalar multiplications by involving neighboring nodes in this operation. In order to improve the reliability, we have also proposed a fault tolerance mechanism. It uses half of the available cluster members as backup nodes which take over the work of faulty nodes in case of system failure. Parallel computing does consume more resources, but the results of simulation show that the computation can be significantly accelerated. This method is designed specially for applications where running time is the most important factor

Wireless sensor network system helping navigation of the visually impaired

International audienceNavigation aids for the pedestrians are considered new research challenges. The visually impaired are particularly concerned, because of their need to detect and avoid obstacles, as well as to orient themselves in unknown environments. In this paper, we discuss some existing projects in this domain and we propose a novel aid system formed of wireless sensors, meant to help navigation of the visually impaired, which addresses both orientation and obstacle negotiation. The proposed system is GPS-free and does not need external assistance in navigation

A Survey of Fast Scalar Multiplication on Elliptic Curve Cryptography for Lightweight Embedded Devices

Elliptic curve cryptography (ECC) is one of the most famous asymmetric cryptographic schemes which offers the same level of security with much shorter keys than the other widely used asymmetric cryptographic algorithm, Rivest, Shamir, and Adleman (RSA). In ECC, the main and most heavily used operation is the scalar multiplication kP, where the scalar value k is a private integer and must be secured. Various methods for fast scalar multiplication are based on the binary/ternary representation of the scalar. In this chapter, we present various methods to make fast scalar multiplication on ECC over prime field for lightweight embedded devices like wireless sensor network (WSN) and Internet of Things (IoT)

Wireless Sensor Network Infrastructure: Construction and Evaluation

International audienceLarge area wireless sensor deployments rely on multi-hop communications. Efficient packet transmissions and virtual topologies, which structure sensor networks, are two main features for efficient energy management in wireless sensor networks. This paper aims to present a distributed and low-cost topology construction algorithm for wireless sensor networks, addressing the following issues: large-scale, random network deployment, energy efficiency and small overhead. We propose structuring nodes in zones, meant to reduce the global view of the network to a local one. This zone-based architecture is the infrastructure used by our hierarchical routing protocol. The experimental results show that the proposed algorithm has low overhead and is scalable

A Hybrid Cluster and Chain-based Routing Protocol for Lifetime Improvement

International audienceThe main challenge in the field of Wireless Sensor Networks (WSNs) is the energy conservation as long as possible. Clustering paradigm has proven its ability to prolong the network lifetime. The present paper proposes two algorithms using an approach that combines fuzzy c-means and ant colony optimization to form the clusters and manage the transmission of data in the network. First, fuzzy c-means is used to construct a predefined number of clusters. Second, we apply Ant Colony Optimization (ACO) algorithm to form a local shortest chain in each cluster. A leader node is randomly chosen at the beginning since all cluster nodes have the same amount of energy. In the next transmission, a remaining energy parameter is employed to select leader node. In the first algorithm, leader nodes transmit data in single hop to the distant base station (BS) while in the second the ACO algorithm is applied again to form a global chain between leader nodes and the BS. Simulation results show that the second proposed algorithm consumes less energy and effectively prolongs the network lifetime compared respectively with the first proposed and the LEACH algorithms

Using Data Compression for Delay Constrained Applications in Wireless Sensor Networks

International audienceData compression is a technique used to save energy in Wireless Sensor Networks by reducing the quantity of data transmitted and the number of transmission. Actually, the main cause of energy consumption in WSN is data transmission. There exist critical applications such as delay constrained activities in which the data have to arrive quickly to the Sink for rapid analysis. In this article, we explore the use of data compression algorithms for delay constrained applications by evaluating a recent data compression algorithm for WSN named K-RLE with optimal parameters on an ultra-low power microcontroller from TI MSP430 series. The relevance of the parameter K for the lossy algorithm K-RLE led us to propose and compare two methods to characterize K: the Standard deviation and the Allan deviation. The last one allow us to control the percentage of data modified. Experimental results show that data compression is an energy efficient technique which can also perform in certain cases the global data transfer time (compression plus transmission time) compared to direct transmission