Transitory Master Key Transport Layer Security for WSNs

Security approaches in Wireless Sensor Networks (WSNs) are normally based on symmetric cryptography. Instead of symmetric encryption, some alternative approaches have been developed by using public-key cryptography. However, the higher computational cost represents a hard limitation to their use. In this paper, a new key management protocol is proposed. A transitory symmetric key is used to authenticate nodes in the network during the key establishment. However, pairwise keys are established using asymmetric cryptography. A theoretical analysis shows that the computational effort required by the public key cryptosystem is greatly reduced, while the security of the network is increased with respect to state-of-the-art schemes based on a transitory master key. Moreover, an experimental analysis demonstrates that this proposed approach can reduce the time spent for key establishment by about 35%

Solutions and Tools for Secure Communication in Wireless Sensor Networks

Secure communication is considered a vital requirement in Wireless Sensor Network (WSN) applications. Such a requirement embraces different aspects, including confidentiality, integrity and authenticity of exchanged information, proper management of security material, and effective prevention and reaction against security threats and attacks. However, WSNs are mainly composed of resource-constrained devices. That is, network nodes feature reduced capabilities, especially in terms of memory storage, computing power, transmission rate, and energy availability. As a consequence, assuring secure communication in WSNs results to be more difficult than in other kinds of network. In fact, trading effectiveness of adopted solutions with their efficiency becomes far more important. In addition, specific device classes or technologies may require to design ad hoc security solutions. Also, it is necessary to efficiently manage security material, and dynamically cope with changes of security requirements. Finally, security threats and countermeasures have to be carefully considered since from the network design phase. This Ph.D. dissertion considers secure communication in WSNs, and provides the following contributions. First, we provide a performance evaluation of IEEE 802.15.4 security services. Then, we focus on the ZigBee technology and its security services, and propose possible solutions to some deficiencies and inefficiencies. Second, we present HISS, a highly scalable and efficient key management scheme, able to contrast collusion attacks while displaying a graceful degradation of performance. Third, we present STaR, a software component for WSNs that secures multiple traffic flows at the same time. It is transparent to the application, and provides runtime reconfigurability, thus coping with dynamic changes of security requirements. Finally, we describe ASF, our attack simulation framework for WSNs. Such a tool helps network designers to quantitatively evaluate effects of security attacks, produce an attack ranking based on their severity, and thus select the most appropriate countermeasures

KALwEN: a new practical and interoperable key management scheme for body sensor networks

Key management is the pillar of a security architecture. Body sensor networks (BSNs) pose several challenges–some inherited from wireless sensor networks (WSNs), some unique to themselves–that require a new key management scheme to be tailor-made. The challenge is taken on, and the result is KALwEN, a new parameterized key management scheme that combines the best-suited cryptographic techniques in a seamless framework. KALwEN is user-friendly in the sense that it requires no expert knowledge of a user, and instead only requires a user to follow a simple set of instructions when bootstrapping or extending a network. One of KALwEN's key features is that it allows sensor devices from different manufacturers, which expectedly do not have any pre-shared secret, to establish secure communications with each other. KALwEN is decentralized, such that it does not rely on the availability of a local processing unit (LPU). KALwEN supports secure global broadcast, local broadcast, and local (neighbor-to-neighbor) unicast, while preserving past key secrecy and future key secrecy (FKS). The fact that the cryptographic protocols of KALwEN have been formally verified also makes a convincing case. With both formal verification and experimental evaluation, our results should appeal to theorists and practitioners alike

A Robot-Sensor Network Security Architecture for Monitoring Applications

This paper presents SNSR (Sensor Network Security using Robots), a novel, open, and flexible architecture that improves security in static sensor networks by benefiting from robot-sensor network cooperation. In SNSR, the robot performs sensor node authentication and radio-based localization (enabling centralized topology computation and route establishment) and directly interacts with nodes to send them configurations or receive status and anomaly reports without intermediaries. SNSR operation is divided into stages set in a feedback iterative structure, which enables repeating the execution of stages to adapt to changes, respond to attacks, or detect and correct errors. By exploiting the robot capabilities, SNSR provides high security levels and adaptability without requiring complex mechanisms. This paper presents SNSR, analyzes its security against common attacks, and experimentally validates its performance

A Survey of Cryptography and Key Management Schemes for Wireless Sensor Networks

Wireless sensor networks (WSNs) are made up of a large number of tiny sensors, which can sense, analyze, and communicate information about the outside world. These networks play a significant role in a broad range of fields, from crucial military surveillance applications to monitoring building security. Key management in WSNs is a critical task. While the security and integrity of messages communicated through these networks and the authenticity of the nodes are dependent on the robustness of the key management schemes, designing an efficient key generation, distribution, and revocation scheme is quite challenging. While resource-constrained sensor nodes should not be exposed to computationally demanding asymmetric key algorithms, the use of symmetric key-based systems leaves the entire network vulnerable to several attacks. This chapter provides a comprehensive survey of several well-known cryptographic mechanisms and key management schemes for WSNs

Improving the security of wireless sensor networks

With the rapid technological advancements of sensors, Wireless Sensor Networks (WSNs) have become the main technology for the Internet of Things (IoT). We investigated the security of WSNs in an environmental monitoring system with the goal to improve the overall security. We implemented a Secure Temperature Monitoring System (STMS), which served as our investigational environment. Our results revealed a security flaw found in the bootstrap loader (BSL) password used to protect firmware in the MSP430 MCU chips. We demonstrated how the BSL password could be brute forced in a matter of days. Furthermore, we illustrate how an attacker can reverse engineer firmware and obtain copies of cryptographic keys. We contributed a solution to improve the BSL password and better protect firmware found in the MSP430 chips. The Secure-BSL software we contributed allows the randomization of the BSL password. Our solution increases the brute force time to decades. The impractical brute force time improves the security of firmware and prevents future reverse engineering tactics. In addition, our Secure-BSL software supports two-factor authentication that allows developers to specify a user-defined passphrase to further protect the MSP430 MCU. Our research serves as proof that any security implemented in a WSN environment is broken if an attacker has access to firmware found in sensor devices

Trustworthiness Mechanisms for Long-Distance Networks in Internet of Things

Aquesta tesi té com a objectiu aconseguir un intercanvi de dades fiable en un entorn hostil millorant-ne la confiabilitat mitjançant el disseny d'un model complet que tingui en compte les diferents capes de confiabilitat i mitjançant la implementació de les contramesures associades al model. La tesi se centra en el cas d'ús del projecte SHETLAND-NET, amb l'objectiu de desplegar una arquitectura d'Internet de les coses (IoT) híbrida amb comunicacions LoRa i d'ona ionosfèrica d'incidència gairebé vertical (NVIS) per oferir un servei de telemetria per al monitoratge del “permafrost” a l'Antàrtida. Per complir els objectius de la tesi, en primer lloc, es fa una revisió de l'estat de l'art en confiabilitat per proposar una definició i l'abast del terme de confiança. Partint d'aquí, es dissenya un model de confiabilitat de quatre capes, on cada capa es caracteritza pel seu abast, mètrica per a la quantificació de la confiabilitat, contramesures per a la millora de la confiabilitat i les interdependències amb les altres capes. Aquest model permet el mesurament i l'avaluació de la confiabilitat del cas d'ús a l'Antàrtida. Donades les condicions hostils i les limitacions de la tecnologia utilitzada en aquest cas d’ús, es valida el model i s’avalua el servei de telemetria a través de simulacions en Riverbed Modeler. Per obtenir valors anticipats de la confiabilitat esperada, l'arquitectura proposada es modela per avaluar els resultats amb diferents configuracions previ al seu desplegament en proves de camp. L'arquitectura proposada passa per tres principals iteracions de millora de la confiabilitat. A la primera iteració, s'explora l'ús de mecanismes de consens i gestió de la confiança social per aprofitar la redundància de sensors. En la segona iteració, s’avalua l’ús de protocols de transport moderns per al cas d’ús antàrtic. L’última iteració d’aquesta tesi avalua l’ús d’una arquitectura de xarxa tolerant al retard (DTN) utilitzant el Bundle Protocol (BP) per millorar la confiabilitat del sistema. Finalment, es presenta una prova de concepte (PoC) amb maquinari real que es va desplegar a la campanya antàrtica 2021-2022, descrivint les proves de camp funcionals realitzades a l'Antàrtida i Catalunya.Esta tesis tiene como objetivo lograr un intercambio de datos confiable en un entorno hostil mejorando su confiabilidad mediante el diseño de un modelo completo que tenga en cuenta las diferentes capas de confiabilidad y mediante la implementación de las contramedidas asociadas al modelo. La tesis se centra en el caso de uso del proyecto SHETLAND-NET, con el objetivo de desplegar una arquitectura de Internet de las cosas (IoT) híbrida con comunicaciones LoRa y de onda ionosférica de incidencia casi vertical (NVIS) para ofrecer un servicio de telemetría para el monitoreo del “permafrost” en la Antártida. Para cumplir con los objetivos de la tesis, en primer lugar, se realiza una revisión del estado del arte en confiabilidad para proponer una definición y alcance del término confiabilidad. Partiendo de aquí, se diseña un modelo de confiabilidad de cuatro capas, donde cada capa se caracteriza por su alcance, métrica para la cuantificación de la confiabilidad, contramedidas para la mejora de la confiabilidad y las interdependencias con las otras capas. Este modelo permite la medición y evaluación de la confiabilidad del caso de uso en la Antártida. Dadas las condiciones hostiles y las limitaciones de la tecnología utilizada en este caso de uso, se valida el modelo y se evalúa el servicio de telemetría a través de simulaciones en Riverbed Modeler. Para obtener valores anticipados de la confiabilidad esperada, la arquitectura propuesta es modelada para evaluar los resultados con diferentes configuraciones previo a su despliegue en pruebas de campo. La arquitectura propuesta pasa por tres iteraciones principales de mejora de la confiabilidad. En la primera iteración, se explora el uso de mecanismos de consenso y gestión de la confianza social para aprovechar la redundancia de sensores. En la segunda iteración, se evalúa el uso de protocolos de transporte modernos para el caso de uso antártico. La última iteración de esta tesis evalúa el uso de una arquitectura de red tolerante al retardo (DTN) utilizando el Bundle Protocol (BP) para mejorar la confiabilidad del sistema. Finalmente, se presenta una prueba de concepto (PoC) con hardware real que se desplegó en la campaña antártica 2021-2022, describiendo las pruebas de campo funcionales realizadas en la Antártida y Cataluña.This thesis aims at achieving reliable data exchange over a harsh environment by improving its trustworthiness through the design of a complete model that takes into account the different layers of trustworthiness and through the implementation of the model’s associated countermeasures. The thesis focuses on the use case of the SHETLAND-NET project, aiming to deploy a hybrid Internet of Things (IoT) architecture with LoRa and Near Vertical Incidence Skywave (NVIS) communications to offer a telemetry service for permafrost monitoring in Antarctica. To accomplish the thesis objectives, first, a review of the state of the art in trustworthiness is carried out to propose a definition and scope of the trustworthiness term. From these, a four-layer trustworthiness model is designed, with each layer characterized by its scope, metric for trustworthiness accountability, countermeasures for trustworthiness improvement, and the interdependencies with the other layers. This model enables trustworthiness accountability and assessment of the Antarctic use case. Given the harsh conditions and the limitations of the use technology in this use case, the model is validated and the telemetry service is evaluated through simulations in Riverbed Modeler. To obtain anticipated values of the expected trustworthiness, the proposal has been modeled to evaluate the performance with different configurations prior to its deployment in the field. The proposed architecture goes through three major iterations of trustworthiness improvement. In the first iteration, using social trust management and consensus mechanisms is explored to take advantage of sensor redundancy. In the second iteration, the use of modern transport protocols is evaluated for the Antarctic use case. The final iteration of this thesis assesses using a Delay Tolerant Network (DTN) architecture using the Bundle Protocol (BP) to improve the system’s trustworthiness. Finally, a Proof of Concept (PoC) with real hardware that was deployed in the 2021-2022 Antarctic campaign is presented, describing the functional tests performed in Antarctica and Catalonia

Location dependent key management schemes supported by random selected cell reporters in wireless sensor networks

PhD ThesisIn order to secure vital and critical information inside Wireless Sensor Net- works (WSNs), a security requirement of data con dentiality, authenticity and availability should be guaranteed. The leading key management schemes are those that employ location information to generate security credentials. Therefore, this thesis proposes three novel location-dependent key manage- ment schemes. First, a novel Location-Dependent Key Management Protocol for a Single Base Station (LKMP-SBS) is presented. As a location-dependent scheme, the WSN zone is divided virtually into cells. Then, any event report generated by each particular cell is signed by a new type of endorsement called a cell- reporter signature, where cell-reporters are de ned as a set of nodes selected randomly by the BS out of the nodes located within the particular cell. This system is analysed and proved to outperform other schemes in terms of data security requirements. Regarding the data con dentiality, for three values of z (1,2,3) the improvement is 95%, 90% and 85% respectively when 1000 nodes are compromised. Furthermore, in terms of data authenticity an enhancement of 49%, 24%, 12.5% is gained using our approach with z = 1; 2; 3 respectively when half of all nodes are compromised. Finally, the optimum number of cell reporters is extensively investigated related to the security requirements, it is proven to be z = n 2 . The second contribution is the design of a novel Location-Dependent Key Man- agement Protocol for Multiple Base Stations (LKMP-MBS). In this scheme, di erent strategies of handling the WSN by multiple BSs is investigated. Ac- cordingly, the optimality of the scheme is analysed in terms of the number of cell reporters. Both data con dentiality and authenticity have been proven to be / e / 1 N . The optimum number of cell reporters had been calculated as zopt = n 2M , PM `=1 jz(`) optj = n 2M . Moreover, the security robustness of this scheme is analysed and proved to outperform relevant schemes in terms of data con- dentiality and authenticity. Furthermore, in comparison with LKMP-SBS, the adoption of multiple base stations is shown to be signi cantly important in improving the overall system security. The third contribution is the design of the novel Mobility- Enabled, Location- dependant Key Managment Protocol for Multiple BSs (MELKMP-MBS). This scheme presents a key management scheme, which is capable of serving a WSN with mobile nodes. Several types of handover are presented in order to main- tain the mobile node service availability during its movement between two zones in the network. Accordingly, the communication overhead of MELKMP- MBS is analysed, simulated and compared with the overhead of other schemes. Results show a signi cant improvement over other schemes in terms of han- dover e ciency and communication over head. Furthermore, the optimality of WSN design such as the value of N; n is investigated in terms of communi- cation overhead in all protocols and it is shown that the optimum number of nodes in each cell, which cause the minimum communication overhead in the network , is n = 3 p 2N.Ministry of Higher Education and Scienti c Research in Iraq and the Iraqi Cultural Attach e in Londo

Emerging Communications for Wireless Sensor Networks

Wireless sensor networks are deployed in a rapidly increasing number of arenas, with uses ranging from healthcare monitoring to industrial and environmental safety, as well as new ubiquitous computing devices that are becoming ever more pervasive in our interconnected society. This book presents a range of exciting developments in software communication technologies including some novel applications, such as in high altitude systems, ground heat exchangers and body sensor networks. Authors from leading institutions on four continents present their latest findings in the spirit of exchanging information and stimulating discussion in the WSN community worldwide