Krishna Sampigethaya

AMOEBA: Robust Location Privacy Scheme for VANET

Communication messages in vehicular ad hoc networks (VANET) can be used to locate and track vehicles. While tracking can be beneficial for vehicle navigation, it can also lead to threats on location privacy of vehicle user. In this paper, we address the problem of mitigating unauthorized tracking of vehicles based on their broadcast communications, to enhance the user location privacy in VANET. Compared to other mobile networks, VANET exhibits unique characteristics in terms of vehicular mobility constraints, application requirements such as a safety message broadcast period, and vehicular network connectivity. Based on the observed characteristics, we propose a scheme called AMOEBA, that provides location privacy by utilizing the group navigation of vehicles. By simulating vehicular mobility in freeways and streets, the performance of the proposed scheme is evaluated under VANET application constraints and two passive adversary models. We make use of vehicular groups for anonymous access to location based service applications in VANET, for user privacy protection. The robustness of the user privacy provided is considered under various attacks.

Swing & swap: user-centric approaches towards maximizing location privacy

In wireless networks, the location tracking of devices and vehicles (nodes) based on their identifiable and locatable broadcasts, presents potential threats to the location privacy of their users. While the tracking of nodes can be mitigated to an extent by updating their identifiers to decorrelate their traversed locations, such an approach is still vulnerable to tracking methods that utilize the predictability of node movement to limit the location privacy provided by the identifier updates. On the other hand, since each user may need privacy at different locations and times, a user-centric approach is needed to enable the nodes to independently determine where/when to update their identifiers. However, mitigation of tracking with a user-centric approach is difficult due to the lack of synchronization between updating nodes. This paper addresses the challenges to providing location privacy by identifier updates due to the predictability of node locations and the asynchronous updates, and proposes a user-centric scheme called Swing that increases location privacy by enabling the nodes to loosely synchronize updates when changing their velocity. Further, since each identifier update inherently trades off network service for privacy, the paper also introduces an approach called Swap, which is an extension of Swing, that enables the nodes to exchange their identifiers to potentially maximize the location privacy provided by each update, hence reducing the number of updates needed to meet the desired privacy levels. The performance of the proposed schemes is evaluated under random and restricted pedestrian mobility.

A framework and taxonomy for comparison of electronic voting schemes

Electronic voting is an emerging social application of cryptographic protocols. A vast amount of literature on electronic voting has been developed over the last two decades. In this paper, we provide a framework that classifies these approaches and defines a set of metrics under which their properties can be compared. Such a methodology reveals important differences in security properties between the classes and allows for selection and future design of voting schemes, based on application requirements. We illustrate the use of our framework by analyzing some of the existing electronic voting schemes.

Aviation Cyber–Physical Systems: Foundations for Future Aircraft and Air Transport

A century of revolutionary growth in aviation has made global travel a reality of daily life. Aircraft and air transport overcame a number of formidable challenges and hostilities in the physical world. Success in this arduous pursuit was not without leveraging advances of the “cyber” layer, i.e., digital computing, data storage and networking, and software, in hardware, infrastructures, humans, and processes, within the airframe, in space, and on the ground. The physical world, however, is evolving continuously in the 21st century, contributing traffic growth and diversity, fossil fuel and ozone layer depletion, demographics and economy dynamics, as some major factors in aviation performance equations. In the next 100 years, apart from breakthrough physical advances, such as aircraft structural and electrical designs, we envision aviations progress will depend on conquering cyberspace challenges and adversities, while safely and securely transitioning cyber benefits to the physical world. A tight integration of cyberspace with the physical world streamlines this vision. This paper proposes a novel cyber-physical system (CPS) framework to understand the cyber layer and cyber-physical interactions in aviation, study their impacts, and identify valuable research directions. This paper presents CPS challenges and solutions for aircraft, aviation users, airports, and air traffic management.

A Survey on Mix Networks and Their Secure Applications

Anonymity is a subdiscipline of information hiding, required in a number of applications, such as in electronic voting. For network communications, anonymity can be provided by a mix network (mixnet). A mixnet is a multistage system that uses cryptography and permutations to provide anonymity. The basic idea of a mixnet has evolved into a number of different classes. In addition to presenting the existing mixnet classifications, this paper classifies mixnets based on the verification mechanisms employed for robustness. The construction of mixnets is presented under a common framework to provide insight into both the design and weaknesses of existing solutions. Basic forms of attack on mixnets and the corresponding robustness solutions are reviewed. Comparison with other solutions for anonymity and suggestions for interesting future research in mix networks are also provided

Future E-Enabled Aircraft Communications and Security: The Next 20 Years and Beyond

Aircraft data communications and networking are key enablers for civilian air transportation systems to meet projected aviation demands of the next 20 years and beyond. In this paper, we show how the envisioned e-enabled aircraft plays a central role in streamlining system modernization efforts. We show why performance targets such as safety, security, capacity, efficiency, environmental benefit, travel comfort, and convenience will heavily depend on communications, networking and cyber-physical security capabilities of the e-enabled aircraft. The paper provides a comprehensive overview of the state-of-the-art research and standardization efforts. We highlight unique challenges, recent advances, and open problems in enhancing operations as well as certification of the future e-enabled aircraft.

Secure Operation, Control, and Maintenance of Future E-Enabled Airplanes

Commercial aviation is at the threshold of the era of the e-enabled airplane, brought about by the convergence of rapidly expanding worldwide data communication infrastructures, network-centric information processing, and commoditized lightweight computational hardware. With advanced avionics, processing, and wireless communication capabilities, the e-enabled airplane can revolutionize the current air transportation system. However, the use of unregulated information technology and wireless technologies introduces vulnerabilities that can be exploited to provide unauthorized access to the onboard aviation information systems and impede their operation. The emerging security threats are not covered by current aviation guidance, and regulations, hence, remain to be addressed. This paper presents a comprehensive survey of security of the e-enabled airplane with applications such as electronic distribution of loadable software and data, as well as future directions such as wireless health monitoring, networked control, and airborne ad hoc networks.

Special Issue on Cyber - Physical Systems [Scanning the Issue]

This Special Issue presents papers that cover key features of Cyber - Physical Systems (CPS), including new research and technology advances, open problems, and technical challenges with the papers organized into three categories: theoretical foundations, small-scale applications, and large-scale applications.

Impact of Public Key Enabled Applications on the Operation and Maintenance of Commercial Airplanes

Making airplanes network-enabled can significantly increase the efficiency of aircraft manufacturing, operation and maintenance processes. Yet these benefits cannot be realized without addressing the potential for network-induced security threats. This paper addresses challenges that emerge for network-enabled airplanes that use public key cryptography-based applications. In particular, we focus on the electronic distribution of airplane software and data. We present both an ad hoc approach, without trust chains between certificates, and a structured approach employing a PKI. Both approaches facilitate public key-enabled applications, and both levy operational requirements on airlines. We describe the integration of these requirements into existing airline ground infrastructure and processes, to minimize operating overhead. The presented work is based on ongoing collaborative efforts among Boeing, FAA and EASA, to identify needs of the airlines for operating and maintaining network-enabled airplanes.

Electronic distribution of airplane software and the impact of information security on airplane safety

The general trend towards ubiquitous networking has reached the realm of airplanes. E-enabled airplanes with wired and wireless network interfaces offer a wide spectrum of network applications, in particular electronic distribution of software (EDS), and onboard collection and off-board retrieval of airplane health reports. On the other hand, airplane safety may be heavily dependent on the security of data transported in these applications. The FAA mandates safety regulations and policies for the design and development of airplane software to ensure continued airworthiness. However, data networks have well known security vulnerabilities that can be exploited by attackers to corrupt and/or inhibit the transmission of airplane assets, i.e. software and airplane generated data. The aviation community has recognized the need to address these security threats. This paper explores the role of information security in emerging information technology (IT) infrastructure for distribution of safety-critical and business-critical airplane software and data. We present our threat analysis with related security objectives and state functional and assurance requirements necessary to achieve the objectives, in the spirit of the well-established Common Criteria (CC) for IT security evaluation. The investigation leverages our involvement with FAA standardization efforts. We present security properties of a generic system for electronic distribution of airplane software, and show how the presence of those security properties enhances airplane safety.