Resilient networking in wireless sensor networks

This report deals with security in wireless sensor networks (WSNs), especially in network layer. Multiple secure routing protocols have been proposed in the literature. However, they often use the cryptography to secure routing functionalities. The cryptography alone is not enough to defend against multiple attacks due to the node compromise. Therefore, we need more algorithmic solutions. In this report, we focus on the behavior of routing protocols to determine which properties make them more resilient to attacks. Our aim is to find some answers to the following questions. Are there any existing protocols, not designed initially for security, but which already contain some inherently resilient properties against attacks under which some portion of the network nodes is compromised? If yes, which specific behaviors are making these protocols more resilient? We propose in this report an overview of security strategies for WSNs in general, including existing attacks and defensive measures. In this report we focus at the network layer in particular, and an analysis of the behavior of four particular routing protocols is provided to determine their inherent resiliency to insider attacks. The protocols considered are: Dynamic Source Routing (DSR), Gradient-Based Routing (GBR), Greedy Forwarding (GF) and Random Walk Routing (RWR)

Practical security scheme design for resource-constrained wireless networks

The implementation of ubiquitous computing (or pervasive computing) can leverage various types of resource-constrained wireless networks such as wireless sensor networks and wireless personal area networks. These resource-constrained wireless networks are vulnerable to many malicious attacks that often cause leakage, alteration and destruction of critical information due to the insecurity of wireless communication and the tampers of devices. Meanwhile, the constraints of resources, the lack of centralized management, and the demands of mobility of these networks often make traditional security mechanisms inefficient or infeasible. So, the resource-constrained wireless networks pose new challenges for information assurance and call for practical, efficient and effective solutions. In this research, we focus on wireless sensor networks and aim at enhancing confidentiality, authenticity, availability and integrity, for wireless sensor networks. Particularly, we identify three important problems as our research targets: (1) key management for wireless sensor networks (for confidentiality), (2) filtering false data injection and DoS attacks in wireless sensor networks (for authenticity and availability), and (3) secure network coding (for integrity). We investigate a diversity of malicious attacks against wireless sensor networks and design a number of practical schemes for establishing pairwise keys between sensor nodes, filtering false data injection and DoS attacks, and securing network coding against pollution attacks for wireless sensor networks. Our contributions from this research are fourfold: (1) We give a taxonomy of malicious attacks for wireless sensor networks. (2) We design a group-based key management scheme using deployment knowledge for wireless sensor networks to establish pair-wise keys between sensor nodes. (3) We propose an en-route scheme for filtering false data injection and DoS attacks in wireless sensor networks. (4) We present two efficient schemes for securing normal and XOR network coding against pollution attacks. Simulation and experimental results show that our solutions outperform existing ones and are suitable for resource-constrained wireless sensor networks in terms of computation overhead, communication cost, memory requirement, and so on

TRUST-BASED DEFENSE AGAINST INSIDER PACKET DROP ATTACKS IN WIRELESS SENSOR NETWORKS

In most wireless sensor networks (WSNs), sensor nodes generate data packets and send them to the base station (BS) by multi-hop routing paths because of their limited energy and transmission range. The insider packet drop attacks refer to a set of attacks where compromised nodes intentionally drop packets. It is challenging to accurately detect such attacks because packets may also be dropped due to collision, congestion, or other network problems. Trust mechanism is a promising approach to identify inside packet drop attackers. In such an approach, each node will monitor its neighbor's packet forwarding behavior and use this observation to measure the trustworthiness of its neighbors. Once a neighbor's trust value falls below a threshold, it will be considered as an attacker by the monitoring node and excluded from the routing paths so further damage to the network will not be made. In this dissertation, we analyze the limitation of the state-of-the-art trust mechanisms and propose several enhancement techniques to better defend against insider packet drop attacks in WSNs. First, we observe that inside attackers can easily defeat the current trust mechanisms and even if they are caught, normally a lot of damage has already been made to the network. We believe this is caused by current trust models' inefficiency in distinguishing attacking behaviors and normal network transmission failures. We demonstrate that the phenomenon of consecutive packet drops is one fundamental difference between attackers and good sensor nodes and build a hybrid trust model based on it to improve the detection speed and accuracy of current trust models. Second, trust mechanisms give false alarms when they mis-categorize good nodes as attackers. Aggressive mechanisms like our hybrid approach designed to catch attackers as early as possible normally have high false alarm rate. Removing these nodes from routing paths may significantly reduce the performance of the network. We propose a novel false alarm detection and recovery mechanism that can recover the falsely detected good nodes. Next, we show that more intelligent packet drop attackers can launch advanced attacks without being detected by introducing a selective forwarding-based denial-of-service attack that drops only packets from specific victim nodes. We develop effective detection and prevention methods against such attack. We have implemented all the methods we have proposed and conducted extensive simulations with the OPNET network simulator to validate their effectiveness

Secure Routing in Wireless Mesh Networks

Wireless mesh networks (WMNs) have emerged as a promising concept to meet the challenges in next-generation networks such as providing flexible, adaptive, and reconfigurable architecture while offering cost-effective solutions to the service providers. Unlike traditional Wi-Fi networks, with each access point (AP) connected to the wired network, in WMNs only a subset of the APs are required to be connected to the wired network. The APs that are connected to the wired network are called the Internet gateways (IGWs), while the APs that do not have wired connections are called the mesh routers (MRs). The MRs are connected to the IGWs using multi-hop communication. The IGWs provide access to conventional clients and interconnect ad hoc, sensor, cellular, and other networks to the Internet. However, most of the existing routing protocols for WMNs are extensions of protocols originally designed for mobile ad hoc networks (MANETs) and thus they perform sub-optimally. Moreover, most routing protocols for WMNs are designed without security issues in mind, where the nodes are all assumed to be honest. In practical deployment scenarios, this assumption does not hold. This chapter provides a comprehensive overview of security issues in WMNs and then particularly focuses on secure routing in these networks. First, it identifies security vulnerabilities in the medium access control (MAC) and the network layers. Various possibilities of compromising data confidentiality, data integrity, replay attacks and offline cryptanalysis are also discussed. Then various types of attacks in the MAC and the network layers are discussed. After enumerating the various types of attacks on the MAC and the network layer, the chapter briefly discusses on some of the preventive mechanisms for these attacks.Comment: 44 pages, 17 figures, 5 table

A Survey on Wireless Sensor Network Security

Wireless sensor networks (WSNs) have recently attracted a lot of interest in the research community due their wide range of applications. Due to distributed nature of these networks and their deployment in remote areas, these networks are vulnerable to numerous security threats that can adversely affect their proper functioning. This problem is more critical if the network is deployed for some mission-critical applications such as in a tactical battlefield. Random failure of nodes is also very likely in real-life deployment scenarios. Due to resource constraints in the sensor nodes, traditional security mechanisms with large overhead of computation and communication are infeasible in WSNs. Security in sensor networks is, therefore, a particularly challenging task. This paper discusses the current state of the art in security mechanisms for WSNs. Various types of attacks are discussed and their countermeasures presented. A brief discussion on the future direction of research in WSN security is also included.Comment: 24 pages, 4 figures, 2 table

Detection of Hidden Wormhole Attack in Wireless Sensor Networks using Neighborhood and Connectivity Information

Wireless sensor networks (WSNs) have inspired many applications such as military applications, environmental monitoring and other fields. WSN has emergence in various fields, so security is very important issue for sensor networks. Security comes from attacks. Due to the wireless and distributed nature anyone can connect with the network. Among all possible attacks, wormholes are very hard to detect because they can cause damage to the network without knowing the protocols used in the network. It is a powerful attack that can be conducted without requiring any cryptographic breaks. Wormholes are hard to detect because they use a private, out-of-band channel invisible to the underlying sensor network. In this paper we have proposed a wormhole detection protocol based on neighborhood and connectivity information. Performance analysis shows that our proposed approach can effectively detect wormhole attack with less storage cost. Keywords: Wireless sensor network, wormhole, out-of-band, security, neighborhood

DI-SEC: Distributed Security Framework for Heterogeneous Wireless Sensor Networks

Wireless Sensor Networks (WSNs) are deployed for monitoring in a range of critical domains (e.g., health care, military, critical infrastructure). Accordingly, these WSNs should be resilient to attacks. The current approach to defending against malicious threats is to develop and deploy a specific defense mechanism for a specific attack. However, the problem with this traditional approach to defending sensor networks is that the solution for one attack (i.e., Jamming attack) does not defend against other attacks (e.g., Sybil and Selective Forwarding). This work addresses the challenges with the traditional approach to securing sensor networks and presents a comprehensive framework, Di-Sec, that can defend against all known and forthcoming attacks. At the heart of Di-Sec lies the monitoring core (M-Core), which is an extensible and lightweight layer that gathers information and statistics relevant for creating defense modules. Along with Di-Sec, a new user-friendly domain-specific language was developed, the M-Core Control Language (MCL). Using the MCL, a user can implement new defense mechanisms without the overhead of learning the details of the underlying software architecture (i.e., TinyOS, Di-Sec). Hence, the MCL expedites the development of sensor defense mechanisms by significantly simplifying the coding process for developers. The Di-Sec framework has been implemented and tested on real sensors to evaluate its feasibility and performance. Our evaluation shows that Di-Sec is feasible on today’s resource-limited sensors and has a nominal overhead. Furthermore, we illustrate the functionality of Di-Sec by implementing four detection and defense mechanisms for attacks at various layers of the communication stack