Biblio

Several efforts are currently active in dealing with scenarios combining fog, cloud computing, out of which a significant proportion is devoted to control, and manage the resulting scenario. Certainly, although many challenging aspects must be considered towards the design of an efficient management solution, it is with no doubt that whatever the solution is, the quality delivered to the users when executing services and the security guarantees provided to the users are two key aspects to be considered in the whole design. Unfortunately, both requirements are often non-convergent, thus making a solution suitably addressing both aspects is a challenging task. In this paper, we propose a decoupled transversal security strategy, referred to as DCF, as a novel architectural oriented policy handling the QoS-Security trade-off, particularly designed to be applied to combined fog-to-cloud systems, and specifically highlighting its impact on the delivered QoS.

Augmented reality (AR) technologies are rapidly being adopted across multiple sectors, but little work has been done to ensure the security of such systems against potentially harmful or distracting visual output produced by malicious or bug-ridden applications. Past research has proposed to incorporate manually specified policies into AR devices to constrain their visual output. However, these policies can be cumbersome to specify and implement, and may not generalize well to complex and unpredictable environmental conditions. We propose a method for generating adaptive policies to secure visual output in AR systems using deep reinforcement learning. This approach utilizes a local fog computing node, which runs training simulations to automatically learn an appropriate policy for filtering potentially malicious or distracting content produced by an application. Through empirical evaluations, we show that these policies are able to intelligently displace AR content to reduce obstruction of real-world objects, while maintaining a favorable user experience.

With the advent of deep learning based methods, facial recognition algorithms have become more effective and efficient. However, these algorithms have usually the disadvantage of requiring the use of dedicated hardware devices, such as graphical processing units (GPUs), which pose restrictions on their usage on embedded devices with limited computational power. In this paper, we present an approach that allows building an intrusion detection system, based on face recognition, running on embedded devices. It relies on deep learning techniques and does not exploit the GPUs. Face recognition is performed using a knn classifier on features extracted from a 50-layers Residual Network (ResNet-50) trained on the VGGFace2 dataset. In our experiment, we determined the optimal confidence threshold that allows distinguishing legitimate users from intruders. In order to validate the proposed system, we created a ground truth composed of 15,393 images of faces and 44 identities, captured by two smart cameras placed in two different offices, in a test period of six months. We show that the obtained results are good both from the efficiency and effectiveness perspective.

Distributed Denial of Service (DDoS) strike is a malevolent undertaking to irritate regular action of a concentrated on server, organization or framework by overwhelming the goal or its incorporating establishment with a flood of Internet development. DDoS ambushes achieve feasibility by utilizing different exchanged off PC structures as wellsprings of strike action. Mishandled machines can join PCs and other masterminded resources, for instance, IoT contraptions. From an anomalous express, a DDoS attack looks like a vehicle convergence ceasing up with the road, shielding standard action from meeting up at its pined for objective.

Everyday., the DoS/DDoS attacks are increasing all over the world and the ways attackers are using changing continuously. This increase and variety on the attacks are affecting the governments, institutions, organizations and corporations in a bad way. Every successful attack is causing them to lose money and lose reputation in return. This paper presents an introduction to a method which can show what the attack and where the attack based on. This is tried to be achieved with using clustering algorithm DBSCAN on network traffic because of the change and variety in attack vectors.

Denial-of-Service attack (DoS attack) is an attack on network in which an attacker tries to disrupt the availability of network resources by overwhelming the target network with attack packets. In DoS attack it is typically done using a single source, and in a Distributed Denial-of-Service attack (DDoS attack), like the name suggests, multiple sources are used to flood the incoming traffic of victim. Typically, such attacks use vulnerabilities of Domain Name System (DNS) protocol and IP spoofing to disrupt the normal functioning of service provider or Internet user. The attacks involving DNS, or attacks exploiting vulnerabilities of DNS are known as DNS based DDOS attacks. Many of the proposed DNS based DDoS solutions try to prevent/mitigate such attacks using some intelligent non-``network layer'' (typically application layer) protocols. Utilizing the flexibility and programmability aspects of Software Defined Networks (SDN), via this proposed doctoral research it is intended to make underlying network intelligent enough so as to prevent DNS based DDoS attacks.

Vehicular ad hoc networks (VANETs) are eminent type of Mobile ad hoc Networks. The network created in VANETs is quite prone to security problem. In this work, a new mechanism is proposed to study the security of VANETs against DDoS attack. The proposed mechanism focuses on distributed denial of service attacks. The main idea of the paper is to detect the DDoS attack and mitigate it. The work consists of two stages, initially attack topology and network congestion is created. The second stage is to detect and mitigate the DDoS attack. The existing method is compared with the proposed method for mitigating DDoS attacks in VANETs. The existing solutions presented by the various researchers are also compared and analyzed. The solution for such kind of problem is provided which is used to detect and mitigate DDoS attack by using greedy approach. The network environment is created using NS-2. The results of simulation represent that the proposed approach is better in the terms of network packet loss, routing overhead and network throughput.

Internet of Things (IoT) offers new opportunities for business, technology and science but it also raises new challenges in terms of security and privacy, mainly because of the inherent characteristics of this environment: IoT devices come from a variety of manufacturers and operators and these devices suffer from constrained resources in terms of computation, communication and storage. In this paper, we address the problem of trust establishment for IoT and propose a security solution that consists of a secure bootstrap mechanism for device identification as well as a message attestation mechanism for aggregate response validation. To achieve both security requirements, we approach the problem in a confined environment, named SubNets of Things (SNoT), where various devices depend on it. In this context, devices are uniquely and securely identified thanks to their environment and their role within it. Additionally, the underlying message authentication technique features signature aggregation and hence, generates one compact response on behalf of all devices in the subnet.

The growing number of devices we interact with require a convenient yet secure solution for user identification, authorization and authentication. Current approaches are cumbersome, susceptible to eavesdropping and relay attacks, or energy inefficient. In this paper, we propose a body-guided communication mechanism to secure every touch when users interact with a variety of devices and objects. The method is implemented in a hardware token worn on user's body, for example in the form of a wristband, which interacts with a receiver embedded inside the touched device through a body-guided channel established when the user touches the device. Experiments show low-power (uJ/bit) operation while achieving superior resilience to attacks, with the received signal at the intended receiver through the body channel being at least 20dB higher than that of an adversary in cm range.

The timing characteristics of cache, a high-speed storage between the fast CPU and the slow memory, may reveal sensitive information of a program, thus allowing an adversary to conduct side-channel attacks. Existing methods for detecting timing leaks either ignore cache all together or focus only on passive leaks generated by the program itself, without considering leaks that are made possible by concurrently running some other threads. In this work, we show that timing-leak-freedom is not a compositional property: a program that is not leaky when running alone may become leaky when interleaved with other threads. Thus, we develop a new method, named adversarial symbolic execution, to detect such leaks. It systematically explores both the feasible program paths and their interleavings while modeling the cache, and leverages an SMT solver to decide if there are timing leaks. We have implemented our method in LLVM and evaluated it on a set of real-world ciphers with 14,455 lines of C code in total. Our experiments demonstrate both the efficiency of our method and its effectiveness in detecting side-channel leaks.

Formal security verification of firmware interacting with hardware in modern Systems-on-Chip (SoCs) is a critical research problem. This faces the following challenges: (1) design complexity and heterogeneity, (2) semantics gaps between software and hardware, (3) concurrency between firmware/hardware and between Intellectual Property Blocks (IPs), and (4) expensive bit-precise reasoning. In this paper, we present a co-verification methodology to address these challenges. We model hardware using the Instruction-Level Abstraction (ILA), capturing firmware-visible behavior at the architecture level. This enables integrating hardware behavior with firmware in each IP into a single thread. The co-verification with multiple firmware across IPs is formulated as a multi-threaded program verification problem, for which we leverage software verification techniques. We also propose an optimization using abstraction to prevent expensive bit-precise reasoning. The evaluation of our methodology on an industry SoC Secure Boot design demonstrates its applicability in SoC security verification.

Just like bugs in single-threaded programs can lead to vulnerabilities, bugs in multithreaded programs can also lead to concurrency attacks. We studied 31 real-world concurrency attacks, including privilege escalations, hijacking code executions, and bypassing security checks. We found that compared to concurrency bugs' traditional consequences (e.g., program crashes), concurrency attacks' consequences are often implicit, extremely hard to be observed and diagnosed by program developers. Moreover, in addition to bug-inducing inputs, extra subtle inputs are often needed to trigger the attacks. These subtle features make existing tools ineffective to detect concurrency attacks. To tackle this problem, we present OWL, the first practical tool that models general concurrency attacks' implicit consequences and automatically detects them. We implemented OWL in Linux and successfully detected five new concurrency attacks, including three confirmed and fixed by developers, and two exploited from previously known and well-studied concurrency bugs. OWL has also detected seven known concurrency attacks. Our evaluation shows that OWL eliminates 94.1% of the reports generated by existing concurrency bug detectors as false positive, greatly reducing developers' efforts on diagnosis. All OWL source code, concurrency attack exploit scripts, and results are available on github.com/hku-systems/owl.

We explore a new security model for secure computation on large datasets. We assume that two servers have been employed to compute on private data that was collected from many users, and, in order to improve the efficiency of their computation, we establish a new tradeoff with privacy. Specifically, instead of claiming that the servers learn nothing about the input values, we claim that what they do learn from the computation preserves the differential privacy of the input. Leveraging this relaxation of the security model allows us to build a protocol that leaks some information in the form of access patterns to memory, while also providing a formal bound on what is learned from the leakage. We then demonstrate that this leakage is useful in a broad class of computations. We show that computations such as histograms, PageRank and matrix factorization, which can be performed in common graph-parallel frameworks such as MapReduce or Pregel, benefit from our relaxation. We implement a protocol for securely executing graph-parallel computations, and evaluate the performance on the three examples just mentioned above. We demonstrate marked improvement over prior implementations for these computations.

While deep learning has shown a great potential in various domains, the lack of transparency has limited its application in security or safety-critical areas. Existing research has attempted to develop explanation techniques to provide interpretable explanations for each classification decision. Unfortunately, current methods are optimized for non-security tasks ( e.g., image analysis). Their key assumptions are often violated in security applications, leading to a poor explanation fidelity. In this paper, we propose LEMNA, a high-fidelity explanation method dedicated for security applications. Given an input data sample, LEMNA generates a small set of interpretable features to explain how the input sample is classified. The core idea is to approximate a local area of the complex deep learning decision boundary using a simple interpretable model. The local interpretable model is specially designed to (1) handle feature dependency to better work with security applications ( e.g., binary code analysis); and (2) handle nonlinear local boundaries to boost explanation fidelity. We evaluate our system using two popular deep learning applications in security (a malware classifier, and a function start detector for binary reverse-engineering). Extensive evaluations show that LEMNA's explanation has a much higher fidelity level compared to existing methods. In addition, we demonstrate practical use cases of LEMNA to help machine learning developers to validate model behavior, troubleshoot classification errors, and automatically patch the errors of the target models.

The intrinsic use of SDN/NFV technologies in 5G infrastructures promise to enable the flexibility and programmability of networks to ensure lower cost of network and service provisioning and operation, however it brings new challenges and requirements due to new architectural changes. In terms of security, authentication and authorization functions need to evolve towards the new and emerging 5G virtualization platforms in order to meet the requirements of service providers and infrastructure operators. Over the years, a lot of authentication techniques have been used. Now, a wide range of options arise allowing to extend existing authentication and authorization mechanisms. This paper focuses on proposing and showcasing a 5G platform oriented solution among different approaches to integrate authentication and authorization functionalities, an adapted secure and stateless mechanism, providing identity and permissions management to handle not only users, but also system micro-services, in a network functions virtualization management and orchestration (NFV MANO) system, oriented to deploy virtualized services. The presented solution uses the NFV-based SONATA Service Platform which offers capabilities for a continuous integration and delivery DevOps methodology that allow high levels of programmability and flexibility to manage the entire life cycle of Virtual Network Functions, and enables the perfect scenario to showcase different approaches for authentication and authorization mechanisms for users and micro-services in a 5G platform.

Security is a vital aspect of industrial control systems since they are used in critical infrastructures and manufacturing processes. As demonstrated by the increasing number of emerging exploits, securing such systems is still a challenge as the employed fieldbus technologies do not offer intrinsic support for basic security objectives. In this work we discuss some security aspects of DeviceNet, a communication protocol widely used for control applications especially in the North American industrial sector. Having the Controller Area Network (CAN) protocol at its base, DeviceNet inherits all the vulnerabilities that were already illustrated on CAN in-vehicle communication. We discuss how the lack of security in DeviceNet can be exploited and point on the fact that these vulnerabilities can be modelled by existing formal verification tools and countermeasures can be put in place.

In this paper, we present an embodied conversational agent (ECA) that includes a cognitive-affective architecture based on the Soar cognitive architecture, integrates an emotion model based on ALMA that uses a three-layered model of emotions, mood and personality, from the point of view of the user and the agent. These features allow to modify the behavior and personality of the agent to achieve a more realistic and believable interaction with the user. This ECA works as a virtual assistant to search information from Wikipedia and show personalized results to the user. It is only a prototipe, but can be used to show some of the possibilities of the system. A first evaluation was conducted to prove these possibilities, with satisfactory results that also give guidance for some future work that can be done with this ECA.

An important ingredient for a successful recipe for solving machine learning problems is the availability of a suitable dataset. However, such a dataset may have to be extracted from a large unstructured and semi-structured data like programming code, scripts, and text. In this work, we propose a plug-in based, extensible feature extraction framework for which we have prototyped as a tool. The proposed framework is demonstrated by extracting features from two different sources of semi-structured and unstructured data. The semi-structured data comprised of web page and script based data whereas the other data was taken from email data for spam filtering. The usefulness of the tool was also assessed on the aspect of ease of programming.

Click-through rate prediction is an essential task in industrial applications, such as online advertising. Recently deep learning based models have been proposed, which follow a similar Embedding&MLP paradigm. In these methods large scale sparse input features are first mapped into low dimensional embedding vectors, and then transformed into fixed-length vectors in a group-wise manner, finally concatenated together to fed into a multilayer perceptron (MLP) to learn the nonlinear relations among features. In this way, user features are compressed into a fixed-length representation vector, in regardless of what candidate ads are. The use of fixed-length vector will be a bottleneck, which brings difficulty for Embedding&MLP methods to capture user's diverse interests effectively from rich historical behaviors. In this paper, we propose a novel model: Deep Interest Network (DIN) which tackles this challenge by designing a local activation unit to adaptively learn the representation of user interests from historical behaviors with respect to a certain ad. This representation vector varies over different ads, improving the expressive ability of model greatly. Besides, we develop two techniques: mini-batch aware regularization and data adaptive activation function which can help training industrial deep networks with hundreds of millions of parameters. Experiments on two public datasets as well as an Alibaba real production dataset with over 2 billion samples demonstrate the effectiveness of proposed approaches, which achieve superior performance compared with state-of-the-art methods. DIN now has been successfully deployed in the online display advertising system in Alibaba, serving the main traffic.

Traditional image compressed sensing (CS) coding frameworks solve an inverse problem that is based on the measurement coding tools (prediction, quantization, entropy coding, etc.) and the optimization based image reconstruction method. These CS coding frameworks face the challenges of improving the coding efficiency at the encoder, while also suffering from high computational complexity at the decoder. In this paper, we move forward a step and propose a novel deep network based CS coding framework of natural images, which consists of three sub-networks: sampling sub-network, offset sub-network and reconstruction sub-network that responsible for sampling, quantization and reconstruction, respectively. By cooperatively utilizing these sub-networks, it can be trained in the form of an end-to-end metric with a proposed rate-distortion optimization loss function. The proposed framework not only improves the coding performance, but also reduces the computational cost of the image reconstruction dramatically. Experimental results on benchmark datasets demonstrate that the proposed method is capable of achieving superior rate-distortion performance against state-of-the-art methods.

In Cloud Manufacturing trust is an important, under investigated issue. This paper proceeds the noncommittal phase of the grounded theory method approach by investigating the trust topic in several research streams, defining the problem domain. This novel approach fills a research gap and can be treated as a snapshot and blueprint of research. Findings were accomplished by a structured literature review and are able to help future researchers in pursuing the integrative phase in Grounded Theory by building on the preliminary result of this paper.

Social media have become increasingly popular for the sharing and spreading of user-generated content due to their easy access, fast dissemination, and low cost. Meanwhile, social media also enable the wide propagation of cyber frauds, which leverage fake information sources to reach an ulterior goal. The prevalence of untrustworthy information sources on social media can have significant negative societal effects. In a trustworthy social media system, trust calculation technology has become a key demand for the identification of information sources. Trust, as one of the most complex concepts in network communities, has multi-criteria properties. However, the existing work only focuses on single trust factor, and does not consider the complexity of trust relationships in social computing completely. In this paper, a multi-criteria trustworthiness calculation mechanism called Info-Trust is proposed for information sources, in which identity-based trust, behavior-based trust, relation-based trust, and feedback-based trust factors are incorporated to present an accuracy-enhanced full view of trustworthiness evaluation of information sources. More importantly, the weights of these factors are dynamically assigned by the ordered weighted averaging and weighted moving average (OWA-WMA) combination algorithm. This mechanism surpasses the limitations of existing approaches in which the weights are assigned subjectively. The experimental results based on the real-world datasets from Sina Weibo demonstrate that the proposed mechanism achieves greater accuracy and adaptability in trustworthiness identification of the network information.

Finite-state machine-based scenario-aware dataflow (FSM-SADF) is a dynamic dataflow model of computation that combines streaming data and finite-state control. For the most part, it preserves the determinism of its underlying synchronous dataflow (SDF) concurrency model and only when necessary introduces the non-deterministic variation in terms of scenarios that are represented by SDF graphs. This puts FSM-SADF in a sweet spot in the trade-off space between expressiveness and analyzability. However, FSM-SADF supports no notion of compositionality, which hampers its usability in modeling and consequent analysis of large systems. In this work we propose a compositional semantics for FSM-SADF that overcomes this problem. We base the semantics of the composition on standard composition of processes with rendezvous communication in the style of CCS or CSP at the control level and the parallel, serial and feedback composition of SDF graphs at the dataflow level. We evaluate the approach on a case study from the multimedia domain.

With the rapid proliferation of mobile users, the spectrum scarcity has become one of the issues that have to be addressed. Cognitive Radio technology addresses this problem by allowing an opportunistic use of the spectrum bands. In cognitive radio networks, unlicensed users can use licensed channels without causing harmful interference to licensed users. However, cognitive radio networks can be subject to different security threats which can cause severe performance degradation. One of the main attacks on these networks is the primary user emulation in which a malicious node emulates the characteristics of the primary user signals. In this paper, we propose a detection technique of this attack based on the RSS-based localization with the maximum likelihood estimation. The simulation results show that the proposed technique outperforms the RSS-based localization method in detecting the primary user emulation attacker.

The gap is widening between the processor clock speed of end-system architectures and network throughput capabilities. It is now physically possible to provide single-flow throughput of speeds up to 100 Gbps, and 400 Gbps will soon be possible. Most current research into high-speed data networking focuses on managing expanding network capabilities within datacenter Local Area Networks (LANs) or efficiently multiplexing millions of relatively small flows through a Wide Area Network (WAN). However, datacenter hyper-convergence places high-throughput networking workloads on general-purpose hardware, and distributed High-Performance Computing (HPC) applications require time-sensitive, high-throughput end-to-end flows (also referred to as ``elephant flows'') to occur over WANs. For these applications, the bottleneck is often the end-system and not the intervening network. Since the problem of the end-system bottleneck was uncovered, many techniques have been developed which address this mismatch with varying degrees of effectiveness. In this survey, we describe the most promising techniques, beginning with network architectures and NIC design, continuing with operating and end-system architectures, and concluding with clean-slate protocol design.