Biblio

The paper presents an example Sensor-cloud architecture that integrates security as its native ingredient. It is based on the multi-layer client-server model with separation of physical and virtual instances of sensors, gateways, application servers and data storage. It proposes the application of virtualised sensor nodes as a prerequisite for increasing security, privacy, reliability and data protection. All main concerns in Sensor-Cloud security are addressed: from secure association, authentication and authorization to privacy and data integrity and protection. The main concept is that securing the virtual instances is easier to implement, manage and audit and the only bottleneck is the physical interaction between real sensor and its virtual reflection.

Large-scale parallel applications with complex global data dependencies beyond those of reductions pose significant scalability challenges in an asynchronous runtime system. Internodal challenges include identifying the all-to-all communication of data dependencies among the nodes. Intranodal challenges include gathering together these data dependencies into usable data objects while avoiding data duplication. This paper addresses these challenges within the context of a large-scale, industrial coal boiler simulation using the Uintah asynchronous many-task runtime system on GPU architectures. We show significant reduction in time spent analyzing data dependencies through refinements in our dependency search algorithm. Multiple task graphs are used to eliminate subsequent analysis when task graphs change in predictable and repeatable ways. Using a combined data store and task scheduler redesign reduces data dependency duplication ensuring that problems fit within host and GPU memory. These modifications did not require any changes to application code or sweeping changes to the Uintah runtime system. We report results running on the DOE Titan system on 119K CPU cores and 7.5K GPUs simultaneously. Our solutions can be generalized to other task dependency problems with global dependencies among thousands of nodes which must be processed efficiently at large scale.

Recent increases in the field of infrastructure has led to the emerging of cloud computing a virtualized computing platform. This technology provides a lot of pros like rapid elasticity, ubiquitous network access and on-demand access etc. Compare to other technologies cloud computing provides many essential services. As the elasticity and scalability increases the chance for vulnerability of the system is also high. There are many known and unknown security risks and challenges present in this environment. In this research an environment is proposed which can handle security issues and deploys various security levels. The system handles the security of various infrastructure like VM and also handles the Dynamic infrastructure request control. One of the key feature of proposed approach is Dual authorization in which all account related data will be authorized by two privileged administrators of the cloud. The auto scalability feature of the cloud is be made secure for on-demand service request handling by providing an on-demand scheduler who will process the on-demand request and assign the required infrastructure. Combining these two approaches provides a secure environment for cloud users as well as handle On-demand Infrastructure request.

The growing volume of data and its increasing complexity require even more efficient and faster information retrieval techniques. Approximate nearest neighbor search algorithms based on hashing were proposed to query high-dimensional datasets due to its high retrieval speed and low storage cost. Recent studies promote the use of Convolutional Neural Network (CNN) with hashing techniques to improve the search accuracy. However, there are challenges to solve in order to find a practical and efficient solution to index CNN features, such as the need for a heavy training process to achieve accurate query results and the critical dependency on data-parameters. In this work we execute exhaustive experiments in order to compare recent methods that are able to produces a better representation of the data space with a less computational cost for a better accuracy by computing the best data-parameter values for optimal sub-space projection exploring the correlations among CNN feature attributes using fractal theory. We give an overview of these different techniques and present our comparative experiments for data representation and retrieval performance.

Secure deployment of a vehicular network depends on the network's trust establishment and privacy-preserving capability. In this paper, we propose a scheme for anonymous pseudonym-renewal and pseudonymous authentication for vehicular ad-hoc networks over a data-centric Internet architecture called Named Data networking (NDN). We incorporated our design in a traffic information sharing demo application and deployed it on Raspberry Pi-based miniature cars for evaluation.

This paper outlines the IoT Databox model as a means of making the Internet of Things (IoT) accountable to individuals. Accountability is a key to building consumer trust and mandated in data protection legislation. We briefly outline the `external' data subject accountability requirement specified in actual legislation in Europe and proposed legislation in the US, and how meeting requirement this turns on surfacing the invisible actions and interactions of connected devices and the social arrangements in which they are embedded. The IoT Databox model is proposed as an in principle means of enabling accountability and providing individuals with the mechanisms needed to build trust in the IoT.

Wireless sensor network operate on the basic underlying assumption that all participating nodes fully collaborate in self-organizing functions. However, performing network functions consumes energy and other resources. Therefore, some network nodes may decide against cooperating with others. Node misbehavior due to selfish or malicious reasons or faulty nodes can significantly degrade the performance of mobile ad-hoc networks. To cope with misbehavior in such self-organized networks, nodes need to be able to automatically adapt their strategy to changing levels of cooperation. The problem of identifying and isolating misbehaving nodes that refuses to forward packets in multi-hop ad hoc networks. a comprehensive system called Audit-based Misbehavior Detection (AMD) that effectively and efficiently isolates both continuous and selective packet droppers. The AMD system integrates reputation management, trustworthy route discovery, and identification of misbehaving nodes based on behavioral audits. AMD evaluates node behavior on a per-packet basis, without employing energy-expensive overhearing techniques or intensive acknowledgment schemes. AMD can detect selective dropping attacks even if end-to-end traffic is encrypted and can be applied to multi-channel networks.

This is a critical time in the design and deployment of Cyber Physical Systems (CPS). Advances in networking, computing, sensing, and control systems have enabled a broad range of new devices and services. Our transportation and medical systems are at the forefront of this advance and rapidly adding cyber components to these existing physical systems. Industry is driven by functional requirements and fast-moving markets and unfortunately security is typically not a driving factor. This can lead to designs were security is an additional feature that will be "bolted on" later. Now is the time to address security. The system designs are evolving rapidly and in most cases design standards are only now beginning to emerge. Many of the devices being deployed today have lifespans measured in decades. The design choices being made today will directly impact next several decades. This talk presents both the challenges and opportunities in building security into the design of these critical systems and will specifically address two emerging challenges. The first challenge considers how we update these devices. Updates involve technical, business, and policy issues. The consequence of an error could be measured in lives lost. The second challenges considers the basic networking approach. These systems may not require traditional networking solutions or traditional security solutions. Content centric networking is an emerging area that is directly applicable to CPS and IoT devices. Content centric networking makes fundamental changes in the core networking concepts, shifting communication from the traditional source/destination model to a new model where forwarding and routing are based on the content sought. In this new model, packets need not even include a source. This talk will argue this model is ideally suited for CPS and IoT environments. A content centric does not just improve the underlying communications system, it fundamentally changes the security and allows designs to move currently intractable security designs to new designs that are both more efficient and more secure.

Emerging computing relies heavily on secure backend storage for the massive size of big data originating from the Internet of Things (IoT) smart devices to the Cloud-hosted web applications. Structured Query Language (SQL) Injection Attack (SQLIA) remains an intruder's exploit of choice to pilfer confidential data from the back-end database with damaging ramifications. The existing approaches were all before the new emerging computing in the context of the Internet big data mining and as such will lack the ability to cope with new signatures concealed in a large volume of web requests over time. Also, these existing approaches were strings lookup approaches aimed at on-premise application domain boundary, not applicable to roaming Cloud-hosted services' edge Software-Defined Network (SDN) to application endpoints with large web request hits. Using a Machine Learning (ML) approach provides scalable big data mining for SQLIA detection and prevention. Unfortunately, the absence of corpus to train a classifier is an issue well known in SQLIA research in applying Artificial Intelligence (AI) techniques. This paper presents an application context pattern-driven corpus to train a supervised learning model. The model is trained with ML algorithms of Two-Class Support Vector Machine (TC SVM) and Two-Class Logistic Regression (TC LR) implemented on Microsoft Azure Machine Learning (MAML) studio to mitigate SQLIA. This scheme presented here, then forms the subject of the empirical evaluation in Receiver Operating Characteristic (ROC) curve.

Testing and fixing Web Application Firewalls (WAFs) are two relevant and complementary challenges for security analysts. Automated testing helps to cost-effectively detect vulnerabilities in a WAF by generating effective test cases, i.e., attacks. Once vulnerabilities have been identified, the WAF needs to be fixed by augmenting its rule set to filter attacks without blocking legitimate requests. However, existing research suggests that rule sets are very difficult to understand and too complex to be manually fixed. In this paper, we formalise the problem of fixing vulnerable WAFs as a combinatorial optimisation problem. To solve it, we propose an automated approach that combines machine learning with multi-objective genetic algorithms. Given a set of legitimate requests and bypassing SQL injection attacks, our approach automatically infers regular expressions that, when added to the WAF's rule set, prevent many attacks while letting legitimate requests go through. Our empirical evaluation based on both open-source and proprietary WAFs shows that the generated filter rules are effective at blocking previously identified and successful SQL injection attacks (recall between 54.6% and 98.3%), while triggering in most cases no or few false positives (false positive rate between 0% and 2%).

The article considers the approach to static analysis of program code and the general principles of static analyzer operation. The authors identify the most important syntactic and semantic information in the programs, which can be used to find errors in the source code. The general methodology for development of diagnostic rules is proposed, which will improve the efficiency of static code analyzers.

As a problem solving method, neural networks have shown broad applicability from medical applications, speech recognition, and natural language processing. This success has even led to implementation of neural network algorithms into hardware. In this paper, we explore two questions: (a) to what extent microelectronic variations affects the quality of results by neural networks; and (b) if the answer to first question represents an opportunity to optimize the implementation of neural network algorithms. Regarding first question, variations are now increasingly common in aggressive process nodes and typically manifest as an increased frequency of timing errors. Combating variations - due to process and/or operating conditions - usually results in increased guardbands in circuit and architectural design, thus reducing the gains from process technology advances. Given the inherent resilience of neural networks due to adaptation of their learning parameters, one would expect the quality of results produced by neural networks to be relatively insensitive to the rising timing error rates caused by increased variations. On the contrary, using two frequently used neural networks (MLP and CNN), our results show that variations can significantly affect the inference accuracy. This paper outlines our assessment methodology and use of a cross-layer evaluation approach that extracts hardware-level errors from twenty different operating conditions and then inject such errors back to the software layer in an attempt to answer the second question posed above.

As the era of cloud technology arises, more and more people are beginning to migrate their applications and personal data to the cloud. This makes web-based applications an attractive target for cyber-attacks. As a result, web-based applications now need more protections than ever. However, current anomaly-based web attack detection approaches face the difficulties like unsatisfying accuracy and lack of generalization. And the rule-based web attack detection can hardly fight unknown attacks and is relatively easy to bypass. Therefore, we propose a novel deep learning approach to detect anomalous requests. Our approach is to first train two Recurrent Neural Networks (RNNs) with the complicated recurrent unit (LSTM unit or GRU unit) to learn the normal request patterns using only normal requests unsupervisedly and then supervisedly train a neural network classifier which takes the output of RNNs as the input to discriminate between anomalous and normal requests. We tested our model on two datasets and the results showed that our model was competitive with the state-of-the-art. Our approach frees us from feature selection. Also to the best of our knowledge, this is the first time that the RNN is applied on anomaly-based web attack detection systems.

Smart Grids (SGs) are Critical Infrastructures (CI), which are responsible for controlling and maintaining the distribution of electricity. To manage this task, modern SGs integrate an Information and Communication Infrastructure (ICT) beside the electrical power grid. Aside from the benefits derived from the increasing control and management capabilities offered by the ICT, unfortunately the introduction of this cyber layer provides an attractive attack surface for hackers. As a consequence, security becomes a fundamental prerequisite to be fulfilled. In this context, the adoption of Systems Engineering (SE) tools combined with Modeling and Simulation (M&S) techniques represent a promising solution to support the evaluation process of a SG during early design stages. In particular, the paper investigates on the identification, modeling and assessment of attacks in SG environments, by proposing a model for representing attack scenarios as a combination of attack types, attack schema and their temporal occurrence. Simulation techniques are exploited to enable the execution of such attack combinations in the SG domain. Specifically, a simulator, which allows to assess the SG behaviour to identify possible flaws and provide preventive actions before its realization, is developed on the basis of the proposed model and exemplified through a case study.

Integration of information technologies with the current power infrastructure promises something further than a smart grid: implementation of smart cities. Power efficient cities will be a significant step toward greener cities and a cleaner environment. However, the extensive use of information technologies in smart cities comes at a cost of reduced privacy. In particular, consumers' power profiles will be accessible by third parties seeking information over consumers' personal habits. In this paper, a methodology for enhancing privacy of electricity consumption patterns is proposed and tested. The proposed method exploits digital connectivity and predictive tools offered via smart grids to morph consumption patterns by grouping consumers via an optimization scheme. To that end, load anticipation, correlation and Theil coefficients are utilized synergistically with genetic algorithms to find an optimal assembly of consumers whose aggregated pattern hides individual consumption features. Results highlight the efficiency of the proposed method in enhancing privacy in the environment of smart cities.

The collection of high frequency metering data in the emerging smart grid gives rise to the concern of consumer privacy. Anonymization of metering data is one of the proposed approaches in the literature, which enables transmission of unmasked data while preserving the privacy of the sender. Distributed anonymization methods can reduce the dependency on service providers, thus promising more privacy for the consumers. However, the distributed communication among the end-users introduces overhead and requires methods to prevent external attacks. In this paper, we propose four variants of a distributed anonymization method for smart metering data privacy, referred to as the Collaborative Anonymity Set Formation (CASF) method. The performance overhead analysis and security analysis of the variants are done using NS-3 simulator and the Scyther tool, respectively. It is shown that the proposed scheme enhances the privacy preservation functionality of an existing anonymization scheme, while being robust against external attacks.

Botnet malware, which infects Internet-connected devices and seizes control for a remote botmaster, is a long-standing threat to Internet-connected users and systems. Botnets are used to conduct DDoS attacks, distributed computing (e.g., mining bitcoins), spread electronic spam and malware, conduct cyberwarfare, conduct click-fraud scams, and steal personal user information. Current approaches to the detection and classification of botnet malware include syntactic, or signature-based, and semantic, or context-based, detection techniques. Both methods have shortcomings and botnets remain a persistent threat. In this paper, we propose a method of botnet detection using Nonparametric Bayesian Methods.

Although anti-virus software has significantly evolved over the last decade, classic signature matching based on byte patterns is still a prevalent concept for identifying security threats. Anti-virus signatures are a simple and fast detection mechanism that can complement more sophisticated analysis strategies. However, if signatures are not designed with care, they can turn from a defensive mechanism into an instrument of attack. In this paper, we present a novel method for automatically deriving signatures from anti-virus software and discuss how the extracted signatures can be used to attack sensible data with the aid of the virus scanner itself. To this end, we study the practicability of our approach using four commercial products and exemplary demonstrate anti-virus assisted attacks in three different scenarios.

A smart grid is a fully automated power electricity network, which operates, protects and controls all its physical environments of power electricity infrastructure being able to supply energy in an efficient and reliable way. As the importance of cyber-physical system (CPS) security is growing, various vulnerability analysis methodologies for general systems have been suggested, whereas there has been few practical research targeting the smart grid infrastructure. In this paper, we highlight the significance of security vulnerability analysis in the smart grid environment. Then we introduce various automated vulnerability analysis techniques from executable files. In our approach, we propose a novel binary-based vulnerability discovery method for AMI and EV charging system to automatically extract security-related features from the embedded software. Finally, we present the test result of vulnerability discovery applied for AMI and EV charging system in Korean smart grid environment.

Many popular web applications incorporate end-toend secure messaging protocols, which seek to ensure that messages sent between users are kept confidential and authenticated, even if the web application's servers are broken into or otherwise compelled into releasing all their data. Protocols that promise such strong security guarantees should be held up to rigorous analysis, since protocol flaws and implementations bugs can easily lead to real-world attacks. We propose a novel methodology that allows protocol designers, implementers, and security analysts to collaboratively verify a protocol using automated tools. The protocol is implemented in ProScript, a new domain-specific language that is designed for writing cryptographic protocol code that can both be executed within JavaScript programs and automatically translated to a readable model in the applied pi calculus. This model can then be analyzed symbolically using ProVerif to find attacks in a variety of threat models. The model can also be used as the basis of a computational proof using CryptoVerif, which reduces the security of the protocol to standard cryptographic assumptions. If ProVerif finds an attack, or if the CryptoVerif proof reveals a weakness, the protocol designer modifies the ProScript protocol code and regenerates the model to enable a new analysis. We demonstrate our methodology by implementing and analyzing a variant of the popular Signal Protocol with only minor differences. We use ProVerif and CryptoVerif to find new and previously-known weaknesses in the protocol and suggest practical countermeasures. Our ProScript protocol code is incorporated within the current release of Cryptocat, a desktop secure messenger application written in JavaScript. Our results indicate that, with disciplined programming and some verification expertise, the systematic analysis of complex cryptographic web applications is now becoming practical.

Thumbnail preserving encryption (TPE) was suggested by Wright et al. [Information Hiding & Multimedia Security Workshop 2015] as a way to balance privacy and usability for online image sharing. The idea is to encrypt a plaintext image into a ciphertext image that has roughly the same thumbnail as well as retaining the original image format. At the same time, TPE allows users to take advantage of much of the functionality of online photo management tools, while still providing some level of privacy against the service provider. In this work we present two new approximate TPE encryption schemes. In our schemes, ciphertexts and plaintexts have perceptually similar, but not identical, thumbnails. Our constructions are the first TPE schemes designed to work well with JPEG compression. In addition, we show that they also have provable security guarantees that characterize precisely what information about the plaintext is leaked by the ciphertext image. We empirically evaluate our schemes according to the similarity of plaintext & ciphertext thumbnails, increase in file size under JPEG compression, preservation of perceptual image hashes, among other aspects. We also show how approximate TPE can be an effective tool to thwart inference attacks by machine-learning image classifiers, which have shown to be effective against other image obfuscation techniques.

Damgard et al. proposed a new primitive called access control encryption (ACE) [6] which not only protects the privacy of the message, but also controls the ability of the sender to send the message. We will give a new construction based on the Learning with Error (LWE) assumption [12], which is one of the two open problems in [6]. Although there are many public key encryption schemes based on LWE and supporting homomorphic operations. We find that not every scheme can be used to build ACE. In order to keep the security and correctness of ACE, the random constant chosen by the sanitizer should satisfy stricter condition. We also give a different security proof of ACE based on LWE from it based on DDH. We will see that although the modulus of LWE should be super-polynomial, the ACE scheme is still as secure as the general public key encryption scheme based on the lattice [5].

Mastery of the subtleties of object-oriented programming lan- guages is undoubtedly challenging to achieve. Design patterns have been proposed some decades ago in order to support soft- ware designers and developers in overcoming recurring challeng- es in the design of object-oriented software systems. However, given that dozens if not hundreds of patterns have emerged so far, it can be assumed that their mastery has become a serious chal- lenge in its own right. In this paper, we describe a proof of con- cept implementation of a recommendation system that aims to detect opportunities for the Strategy design pattern that developers have missed so far. For this purpose, we have formalized natural language pattern guidelines from the literature and quantified them for static code analysis with data mined from a significant collection of open source systems. Moreover, we present the re- sults from analyzing 25 different open source systems with this prototype as it discovered more than 200 candidates for imple- menting the Strategy pattern and the encouraging results of a pre- liminary evaluation with experienced developers. Finally, we sketch how we are currently extending this work to other patterns.

Summary form only given. All-optical switching (AOS) has been observed in ferromagnetic (FM) layers and synthetic ferrimagnetic heterostructures [1-4]. In this work, we use anomalous Hall effect (AHE) measurements to demonstrate controlled helicity-dependent switching in synthetic ferrimagnetic heterostructures. The two FM layers are engineered to have different Curie temperatures Tc1 (fixed) and Tc2 (variable). We show that irrespective of whether Tc2 is higher or lower than Tc1, the final magnetic configuration of the heterostructure is controlled by using the laser polarization to set the magnetic state of the FM layer with the highest Tc. All samples were grown on glass substrates at room temperature by DC magnetron sputtering. Two sets of samples were prepared. The first set are single FM layers with layer composition Ta (3 nm)/Pt (4 nm)/FM1(2)/Pt capping (4 nm), where FM1 = Co (0.6 nm) is a Co layer and FM2 = CoFeB (tCoFeB)/Pt(0.4 nm)/ CoFeB (tCoFeB) (0.2 ≤ tCoFeB ≤ 0.6 nm) is a composite CoFeB layer where both CoFeB layers are ferromagnetically coupled and act as a single layer. FM1 and FM2 were used to produce the second set of synthetic ferrimagnetic samples with layer structure Ta (3 nm)/Pt (4 nm)/FM1/Pt (0.4 nm)/Ru (0.9 nm)/Pt (0.4 nm)/FM2/Pt capping (4 nm). The Ru layer provides the antiferromagnetic RKKY interlayer exchange coupling between the adjacent FM1 and FM2 layers while the Pt layers on either side of the Ru layer can tune the strength of the coupling and stabilize their perpendicular anisotropy [5]. To study the AOS, we use a Ti: sapphire fs-laser with a wavelength of 800 nm and a pulse duration of 43 fs. A quarter-wave plate is used to create a circularly polarized [right(σ+) and left-handed (σ-)] beam. We first measured the magnetic properties of the FM1 and FM2 layers using vibrating sample magnetometry (VSM). All FM samples show full remanence in perpendicular hyst- resis loops at room temperature (not shown). The temperature-dependent magnetization scans (not shown) give a Curie temperature Tc1 of 524 K for FM1. For FM2, increasing tCoFeB increases its Curie temperatureTc2. At tCoFeB = 0.5 nm, Tc2 - Tc1. Hall crosses are patterned by optical lithography and ion milling. The width of the current carrying wire is - 5 um, giving a DC current density of - 6 x 109 A/m2 during the measurement. Figure 1(a) shows the resulting perpendicular Hall hysteresis loop of the synthetic ferrimagnetic sample with tCoFeB = 0.2 nm. At remanence, the stable magnetic configurations are the two antiparallel orientations of FM1 and FM2 [State I and II in Fig. 1(a)]. To study the AOS, we swept the laser beam with a power of 0.45 mW and a speed of 1 μm/sec across the Hall cross, and the corresponding Hall voltage was constantly monitored. In Fig. 1(b), we show the normalized Hall voltage, VHall, as a function of the laser beam position x for both beam polarizations σ+ and σ-. The initial magnetic configuration was State I. When the beam is at the center of the cross (position B), both beam polarizations give VHall - 0. As the beam leaves the cross (position C), the σbeam changes the magnetic configurations from State I to State II (FM1 magnetization pointing down), while the system reverts to State I using the σ+ beam. Changing the initial configuration from State I to State II results in the same final magnetic configurations, determined by the laser beam polarizations (not shown). Similar results (not shown) were obtained for samples with tCoFeB ≤ 0.4 nm. However, at tCoFeB = 0.6 nm, the σbeam results in the final magnetic configurations with FM2 magnetization pointing down (State I) and the σ+ beam results in the State II configuration, suggesting that the final state is determined by the beam polar

Constraints such as separation-of-duty are widely used to specify requirements that supplement basic authorization policies. However, the existence of constraints (and authorization policies) may mean that a user is unable to fulfill her/his organizational duties because access to resources is denied. In short, there is a tension between the need to protect resources (using policies and constraints) and the availability of resources. Recent work on workflow satisfiability and resiliency in access control asks whether this tension compromises the ability of an organization to achieve its objectives. In this paper, we develop a new method of specifying constraints which subsumes much related work and allows a wider range of constraints to be specified. The use of such constraints leads naturally to a range of questions related to "policy existence", where a positive answer means that an organization's objectives can be realized. We provide an overview of our results establishing that some policy existence questions, notably for those instances that are restricted to user-independent constraints, are fixed-parameter tractable.