Given the limited resources and computational power of current embedded sensor devices, memory protection is difficult to achieve and generally unavailable. Hence, the software run-time buffer overflow that is used by the worm attacks in the Internet could be easily exploited to inject malicious codes into wireless sensor networks (WSNs). As a result, the remote attestation on the application codes installed in WSNs is the first important step to detect any unauthorized changes through the buffer overflow attack. Previous software-based remote code verification approaches such as SoftWare-based ATTestation and Secure Code Update By Attestation have been shown difficult to deploy in recent work. In this paper, we propose and implement a remote attestation protocol for detecting unauthorized tampering in the application codes running on sensor nodes with the assistance of Trusted Platform Modules (TPMs), a tiny, cost-effective and tamper-proof cryptographic micro-controller. In our design, each sensor node is equipped with a TPM, and the firmware running on the node could be verified by the other sensor nodes in a WSN, including the sink. Specifically, we present a hardware-based remote attestation protocol, discuss the potential attacks an adversary could launch against the protocol and provide comprehensive system performance results of the protocol in a multi-hop sensor network testbed. The experimental results demonstrated that our scheme is able to attest the application codes running in sensor node with small delay (less than 25 s for single-hop), considerable network lifetime and reasonable communication and energy overhead. Copyright © 2015 John Wiley & Sons, Ltd.

Communications security is a critical and increasingly challenging issue in wireless networks. A well-known approach for achieving information-theoretic secrecy relies on deploying artificial noises to blind the intruders' interception in the physical layer. However, this approach requires a static channel condition for the transmitter and receiver to generate and offset the controllable artificial noise, which can hardly be implemented in real wireless environments. In this paper, we explore the feasibility of symbol obfuscation to defend against the passive eavesdropping attack and fake packet injection attack during the wireless communications. We propose a multiple inter-symbol obfuscation (MIO) scheme, which utilizes a set of artificial noisy symbols (symbols key) to obfuscate the original data symbols in the physical layer. MIO can effectively enhance the wireless communications security. On the one hand, an eavesdropper, without knowing the artificial noisy symbols, cannot correctly decrypt the obfuscated symbols from the eavesdropped packets. On the other hand, a legitimate receiver can easily check the integrity of the symbols key and then reject the fake packets from the received packets. The security analysis reveals that, without considering the initial key, the MIO scheme can achieve information-theoretic secrecy against the passive eavesdropping attack and computational secrecy against the fake packet injection attack. Moreover, we have implemented our approach in a USRP2 testbed and conducted simulations with Simulink tools to validate the effectiveness of MIO in enhancing wireless communications security.

Mobility management is particularly important and challenging in Mobile Ad-hoc Networks (MANETs) because mobile nodes frequently change their locations, which may aggravate the performance in MANETs severely in many aspects (e.g., multi-hop routing). In this paper, we propose a Fuzzy-LogIc based Mobility management Scheme (FLIMS), to manipulate location messages of mobile nodes in MANETs efficiently. To the best of our knowledge, we are the first to employ the fuzzy logic to manage the location messages in mobility management scheme in MANETs. We provide simulation results that illustrate our scheme performs better than the existing schemes.

Current network programming protocols provide an efficient way to update program images running on sensor nodes without having physical access to them. Securing these updates, however, remains a challenging and important issue, given the open environment where sensor nodes are often deployed. Several approaches addressing these issues have been reported, but their use of cryptographically strong protocols means that their computational costs (and hence, power consumption and communication costs) are relatively high. In this paper, we propose a novel scheme to secure a multihop network programming protocol through the use of multiple one-way hash chains. The scheme is shown to be lower in computational, power consumption, and communication costs yet still able to secure multihop propagation of program images. We demonstrate the use of this scheme and provide some results using the popular network programming protocol, Deluge. In addition, we include a performance evaluation of our scheme, implemented in TinyOS, in terms of latency and energy consumption.

Given the limited resources and computational power of current embedded sensor devices memory protection is difficult to achieve and generally unavailable. Hence, the buffer overflow that is used by the worm attacks in the Internet can be easily exploited to inject malicious code into Wireless Sensor Networks (WSNs). We designed a hardware-based remote attestation protocol to counter the buffer overflow attack. In our attestation protocol, each sensor node is equipped with a Trusted Platform Module (TPM) board. The TPM is responsible for content verification of the program flash. To the best of our knowledge, it is the first remote attestation protocol in WSNs with each sensor node equipped with TPM.

This article presents the design and implementation of a trusted sensor node that provides Internet-grade security at low system cost. We describe trustedFleck, which uses a commodity Trusted Platform Module (TPM) chip to extend the capabilities of a standard wireless sensor node to provide security services such as message integrity, confidentiality, authenticity , and system integrity based on RSA public-key and XTEA-based symmetric-key cryptography. In addition trustedFleck provides secure storage of private keys and provides platform configuration registers (PCRs) to store system configurations and detect code tampering. We analyze system performance using metrics that are important for WSN applications such as computation time, memory size, energy consumption and cost. Our results show that trustedFleck significantly outperforms previous approaches (e.g., TinyECC) in terms of these metrics while providing stronger security levels. Finally, we describe a number of examples, built on trustedFleck, of symmetric key management, secure RPC, secure software update, and remote attestation .

Code dissemination protocols provide a convenient way to update program images via wireless communication. Due to the open environment in which Wireless Sensor Networks (WSNs) are typically deployed, it is important that a code dissemination protocol ensures that a program image update can be authenticated as coming from a trusted source. In some applications it is also required that the data be kept confidential in spite of the possibility of message interception. Authentication and confidentiality are implemented through cryptographic operations which may be expensive in power consumption, making a protocol with these features vulnerable to attack by an adversary who transmits forged data, forcing nodes to waste energy in identifying it as invalid i.e., a signature-based DoS attack). Additionally, in multi-hop dissemination protocols, each sensor node is required to broadcast its program image when requested by its neighbors. An adversary could repeatedly send spurious program image requests to its neighbors, making them exhaust their energy reserves i.e., request-based DoS attack). In this paper, we present a new approach to achieve confidentiality in multi-hop code dissemination. We propose counter-measures against both types of DoS attacks mentioned above. To our knowledge, we are the first to integrate confidentiality and DoS-attack-resistance in a multi-hop code dissemination protocol. Our approach is based on Deluge, an open source, state-of-the-art code dissemination protocol for WSNs. In addition, We provide a performance evaluation in terms of latency and energy consumption in our scheme, compared with the original Deluge and the existing secure Deluge.

Current network programming protocols provide an efficient way to update the program image running on sensor nodes without physical access to them. However, given the open environment in which sensor nodes are deployed, securing network programming is a challenging task. Existing work addressing this issue either lack consideration of securing multi-hop network programming protocols, or are not cost-efficient. To our knowledge, none of them have evaluated the power consumption. In this paper, we propose a novel scheme to secure multi-hop network programming protocols using multiple one-way hash chains. This scheme is resilient to malicious program image injection by the compromised nodes and it secures multi-hop propagation of program images for sensor nodes. Based on the most popular network programming protocol, Deluge, an overhead analysis on this schemes is given. In addition, our scheme is implemented in TinyOS and a performance evaluation in terms of latency and energy consumption is presented.

Network routing is a cooperative process. The network performance will be seriously degraded if one or more network components are compromised to network attackers and they behave maliciously. There have been a few literatures to address the robustness of network routing but few of them have holistic countermeasure against them (especially combined misbehavior). In this paper, we propose a novel network protocol to address these imperative issues that have been ignored in existing literature. We present the scalability evaluation of our network protocol through the simulation in NS2. We derive the complete analytical model behind our design. The respective simulation result from NS2 also proves the correctness of the analytical model. The simulation results on the network performance improvement compared to other solutions are also presented.

In the research field of Wireless Sensor Networks (WSN), how to reduce the energy consumption of WSN so that the lifetime of WSN can be prolonged is one of the hottest spots. In this paper, the introduction on the relevant research is given firstly. The hexagon-grid algorithm is proposed to schedule the sensor nodes activities in WSN and the respective analysis is carried out after that. At last, simulation result for the proposed algorithm is presented and the conclusion of this new algorithm is given.