Biblio

Many popular metrics used for the quantification of the quality or complexity of a codebase (e.g. cyclomatic complexity) were developed in the 1970s or 1980s when source code sizes were significantly smaller than they are today, and before a number of modern programming language features were introduced in different languages. Thus, the many thresholds that were suggested by researchers for deciding whether a given function is lacking in a given quality dimension need to be updated. In the pursuit of this goal, we study a number of open-source high-performance codes, each of which has been in development for more than 15 years—a characteristic which we take to imply good design to score them in terms of their source codes' quality and to relax the above-mentioned thresholds. First, we employ the LLVM/Clang compiler infrastructure and introduce a Clang AST tool to gather AST-based metrics, as well as an LLVM IR pass for those based on a source code's static call graph. Second, we perform statistical analysis to identify the reference thresholds of 22 code quality and callgraph-related metrics at a fine grained level.

Privacy and data security are critical aspects in databases, mainly when the latter are publically accessed such in social networks. Furthermore, for advanced databases, such as NoSQL ones, security models and security meta-data must be integrated to the business specification and data. In the literature, the proposed models for NoSQL databases can be considered as static, in the sense where the privileges for a given user are predefined and remain unchanged during job sessions. In this paper, we propose a novel model for NoSQL database access control that we aim that it will be dynamic. To be able to design such model, we have considered the Trust concept to compute the reputation degree for a given user that plays a given role.

In an agricultural supply chain, farmers, food processors, transportation agencies, importers, and exporters must comply with different regulations imposed by one or more jurisdictions depending on the nature of their business operations. Supply chain stakeholders conventionally transport their goods, along with the corresponding documentation via regulators for compliance checks. This is generally followed by a tedious and manual process to ensure the goods meet regulatory requirements. However, supply chain systems are changing through digitization. In digitized supply chains, data is shared with the relevant stakeholders through digital supply chain platforms, including blockchain technology. In such datadriven digital supply chains, the regulators may be able to leverage digital technologies, such as artificial intelligence and machine learning, to automate the compliance verification process. However, a barrier to progress is the risk that information will not be credible, thus reversing the gains that automation could achieve. Automating compliance based on inaccurate data may compromise the safety and credibility of the agricultural supply chain, which discourages regulators and other stakeholders from adopting and relying on automation. Within this article we consider the challenges of digital supply chains when we describe parts of the compliance management process and how it can be automated to improve the operational efficiency of agricultural supply chains. We introduce assisted autonomy as a means to pragmatically automate the compliance verification process by combining the power of digital systems while keeping the human in-the-loop. We argue that autonomous compliance is possible, but that the need for human led inspection processes will never be replaced by machines, however it can be minimised through “assisted autonomy”.

Anecdotal evidence suggests that Web-search engines, together with the Knowledge Graphs and Bases, such as YAGO [46], DBPedia [13], Freebase [16], Google Knowledge Graph [52] provide rapid access to most structured information on the Web. However, taking a closer look reveals a so called "knowledge gap" [18] that is largely in the dark. For example, a person searching for a relevant job opening has to spend at least 3 hours per week for several months [2] just searching job postings on numerous online job-search engines and the employer websites. The reason why this seemingly simple task cannot be completed by typing in a few keyword queries into a search-engine and getting all relevant results in seconds instead of hours is because access to structured data on the Web is still rudimentary. While searching for a job we have many parameters in mind, not just the job title, but also, usually location, salary range, remote work option, given a recent shift to hybrid work places, and many others. Ideally, we would like to write a SQL-style query, selecting all job postings satisfying our requirements, but it is currently impossible, because job postings (and all other) Web tables are structured in many different ways and scattered all over the Web. There is neither a Web-scale generalizable algorithm nor a system to locate and normalize all relevant tables in a category of interest from millions of sources.Here we describe and evaluate on a corpus having hundreds of millions of Web tables [39], a new scalable iterative training data generation algorithm, producing high quality training data required to train Deep- and Machine-learning models, capable of generalizing to Web scale. The models, trained on such en-riched training data efficiently deal with Web scale heterogeneity compared to poor generalization performance of models, trained without enrichment [20], [25], [38]. Such models are instrumental in bridging the knowledge gap for structured data on the Web.

In the industrial control system, in order to solve the problem that the installation of smart devices in a transparent environment are faced with the unknown attack problems, because most of the industrial control equipment to detect unknown risks, Therefore, by studying the security protection of the current industrial control system and the trust mechanism that should be widely used in the Internet of things, this paper presents the abnormal node detection mode based on comprehensive trust applied to the industrial control system scenarios. This model firstly proposes a model, which fuses direct and indirect trust values into current trust values through support algorithm and vector similarity algorithm, and then combines them with historical trust values, and gives the calculation method of each trust value. Finally, a method to determine abnormal nodes based on comprehensive trust degree is given to realize a detection process for all industrial control nodes. By analyzing the real data case provided by Melbourne Water, it is concluded that this model can improve the detection range and detection accuracy of abnormal nodes. It can accurately judge and effectively resist malicious behavior and also have a good resistance to aggression.

Smart grids are one of the most important applications of cyber-physical systems. They intelligently transmit energy to customers by information technology, and have replaced the traditional power grid and are widely used. However, smart grids are vulnerable to cyber-attacks. Once attacked, it will cause great losses and lose the trust of customers. Therefore, it is important to evaluate the trustworthiness of smart grids. In order to evaluate the trustworthiness of smart grids, this paper uses a generalized stochastic Petri net (GSPN) to model smart grids. Considering various security threats that smart grids may face, we propose a general GSPN model for smart grids, which evaluates trustworthiness from three metrics of reliability, availability, and integrity by analyzing steady-state and transient probabilities. Finally, we obtain the value of system trustworthiness and simulation results show that the feasibility and effectiveness of our model for smart grids trustworthiness.

Software trustworthiness includes many attributes. Reasonable weight allocation of trustworthy attributes plays a key role in the software trustworthiness measurement. In practical application, attribute weight usually comes from experts' evaluation to attributes and hidden information derived from attributes. Therefore, when the weight of attributes is researched, it is necessary to consider weight from subjective and objective aspects. Firstly, a novel weight allocation method is proposed by combining the Fuzzy Analytical Hierarchy Process (FAHP) method and the Criteria Importance Though Intercrieria Correlation (CRITIC) method. Secondly, based on the weight allocation method, the trustworthiness measurement models of component-based software are established according to the four combination structures of components. Thirdly, some metric criteria of the model are proved to verify the reasonability. Finally, a case is used to illustrate the practicality of the model.

In electronic warfare, communication may not counter reconnaissance and jamming without the help of network-station selection of frequency hopping. The competition in the field of electromagnetic spectrum is becoming more and more fierce with the increasingly complex electromagnetic environment of modern battlefield. The research on detection, identification, parameter estimation and network station selection of frequency hopping communication network has aroused the interest of scholars both at home and abroad, which has been summarized in this paper. Firstly, the working mode and characteristics of two kinds of FH communication networking modes synchronous orthogonal network and asynchronous non orthogonal network are introduced. Then, through the analysis of FH signals time hopping, frequency hopping, bandwidth, frequency, direction of arrival, bad time-frequency analysis, clustering analysis and machine learning method, the feature-based method is adopted Parameter selection technology is used to sort FH network stations. Finally, the key and difficult points of current research on FH communication network separation technology and the research status of blind source separation technology are introduced in details in this paper.

The widespread utilization of smart grids is due to their flexibility to support the two-way flow of electricity and data. The critical nature of smart grids evokes traditional network attacks. Due to the advantages of blockchains in terms of ensuring trustworthiness and security, a significant body of literature has been recently developed to secure smart grid operations. We categorize the blockchain applications in smart grid into three categories: energy trading, infrastructure management, and smart-grid operations management. This paper provides an extensive survey of these works and the different ways to utilize blockchains in smart grid in general. We propose an abstract system to overcome a critical cyberattack; namely, the fake data injection, as previous works did not consider such an attack.

Video Conferencing has emerged as a new paradigm of communication in the age of COVID-19 pandemic. This technology is allowing us to have real-time interaction during the social distancing era. Even before the current crisis, it was increasingly commonplace for organizations to adopt a video conferencing tool. As people adopt video conferencing tools and access data with potentially less secure equipment and connections, meetings are becoming a target to cyber attackers. Enforcing appropriate security and privacy settings prevents attackers from exploiting the system. To design the video conferencing system's security and privacy model, an exhaustive threat model must be adopted. Threat modeling is a process of optimizing security by identifying objectives, vulnerabilities, and defining the plan to mitigate or prevent potential threats to the system. In this paper, we use the widely accepted STRIDE threat modeling technique to identify all possible risks to video conferencing tools and suggest mitigation strategies for creating a safe and secure system.

Mitigation of dangers posed by authorized and trusted insiders to the organization is a challenging Cyber Security issue. Despite state-of-the-art cyber security practices, malicious insiders present serious threat for the enterprises due to their wider access to organizational resources (Physical, Cyber) and good knowledge of internal processes with potential vulnerabilities. The issue becomes particularly important for isolated (air-gapped) computer networks, normally used by security sensitive organizations such as government, research and development, critical infrastructure (e.g. power, nuclear), finance, and military. Such facilities are difficult to compromise from outside; however, are quite much prone to insider threats. Although many insider threat taxonomies exist for generic computer networks; yet, the existing taxonomies do not effectively address the issue of Insider Threat in isolated computer networks. Thereby, we have developed an insider threat taxonomy specific to isolated computer networks focusing on actions performed by the trusted individual(s), Our methodology is to identify limitations in existing taxonomies and map real world insider threat cases on proposed taxonomy. We argue that for successful attack in an isolated computer network, the attack must manifest in both Physical and Cyber world. The proposed taxonomy systematically classifies different aspects of the problem into separate dimensions and branches out these dimensions into further sub-categories without loss of general applicability. Our multi-dimensional hierarchical taxonomy provides comprehensive treatment of the insider threat problem in isolated computer networks; thus, improving situational awareness of the security analyst and helps in determining proper countermeasures against perceived threats. Although many insider threat taxonomies exist for generic computer networks; yet, the existing taxonomies do not effectively address the issue of Insider Threat in isolated computer networks. Thereby, we have developed an insider threat taxonomy specific to isolated computer networks focusing on actions performed by the trusted individual(s), Our methodology is to identify limitations in existing taxonomies and map real world insider threat cases on proposed taxonomy. We argue that for successful attack in an isolated computer network, the attack must manifest in both Physical and Cyber world. The proposed taxonomy systematically classifies different aspects of the problem into separate dimensions and branches out these dimensions into further sub-categories without loss of general applicability. Our multi-dimensional hierarchical taxonomy provides comprehensive treatment of the insider threat problem in isolated computer networks; thus, improving situational awareness of the security analyst and helps in determining proper countermeasures against perceived threats. The proposed taxonomy systematically classifies different aspects of the problem into separate dimensions and branches out these dimensions into further sub-categories without loss of general applicability. Our multi-dimensional hierarchical taxonomy provides comprehensive treatment of the insider threat problem in isolated computer networks; thus, improving situational awareness of the security analyst and helps in determining proper countermeasures against perceived threats.

Advances in machine learning, deep learning, and Artificial Intelligence(AI) allows people to exchange other people's faces and voices in videos to make it look like what they did or say whatever you want to say. These videos and photos are called “deepfake” and are getting more complicated every day and this has lawmakers worried. This technology uses machine learning technology to provide computers with real data about images, so that we can make forgeries. The creators of Deepfake use artificial intelligence and machine learning algorithms to mimic the work and characteristics of real humans. It differs from counterfeit traditional media because it is difficult to identify. As In the 2020 elections loomed, AI-generated deepfakes were hit the news cycle. DeepFakes threatens facial recognition and online content. This deception can be dangerous, because if used incorrectly, this technique can be abused. Fake video, voice, and audio clips can do enormous damage. This paper examines the algorithms used to generate deepfakes as well as the methods proposed to detect them. We go through the threats, research patterns, and future directions for deepfake technologies in detail. This research provides a detailed description of deep imitation technology and encourages the creation of new and more powerful methods to deal with increasingly severe deep imitation by studying the history of deep imitation.

Software defined networking (SDN) architecture frame- work eases the work of the network administrators by separating the data plane from the control plane. This provides a programmable interface for applications development related to security and management. The centralized logical controller provides more control over the total network, which has complete network visibility. These SDN advantages expose the network to vulnerabilities and the impact of the attacks is much severe when compared to traditional networks, where the network devices have protection from the attacks and limits the occurrence of attacks. In this paper, we proposed an entropy based algorithm in SDN to detect as well as stopping distributed denial of service (DDoS) attacks on the servers or clouds or hosts. Firstly, there explored various attacks that can be launched on SDN at different layers. Basically DDoS is one kind of denial of service attack in which an attacker uses multiple distributed sources for attacking a particular server. Every network in a system has an entropy and an increase in the randomness of probability causes entropy to decrease. In comparison with previous entropy based approaches this approach has higher performance in distinguishing legal and illegal traffics and blocking illegal traffic paths. Linux OS and Mininet Simulator along with POX controller are used to validate the proposed approach. By conducting pervasive simulation along with theoretical analysis this method can definitely detect and stop DDoS attacks automatically.

Threat Intelligence has been a key part of the success of Intrusion Detection, with several trusted sources leading to wide adoption and greater understanding of new and trending threats to computer networks. Identifying potential threats and live attacks on networks is only half the battle, knowing how to correctly respond to these threats and attacks requires in-depth and domain specific knowledge, which may be unique to subject experts and software vendors. Network Incident Responders and Intrusion Response Systems can benefit from a similar approach to Threat Intel, with a focus on potential Response actions. A qualitative comparison of current Threat Intel Sources and prominent Intrusion Response Systems is carried out to aid in the identification of key requirements to be met to enable the adoption of Response Intel. Building on these requirements, a template for Response Intel is proposed which incorporates standardised models developed by MITRE. Similarly, to facilitate the automated use of Response Intel, a structure for automated Response Actions is proposed.

Software vulnerabilities have become a major problem for the security analysts, since the number of new vulnerabilities is constantly growing. Thus, there was a need for a categorization system, in order to group and handle these vulnerabilities in a more efficient way. Hence, the MITRE corporation introduced the Common Weakness Enumeration that is a list of the most common software and hardware vulnerabilities. However, the manual task of understanding and analyzing new vulnerabilities by security experts, is a very slow and exhausting process. For this reason, a new automated classification methodology is introduced in this paper, based on the vulnerability textual descriptions from National Vulnerability Database. The proposed methodology, combines textual analysis and tree-based machine learning techniques in order to classify vulnerabilities automatically. The results of the experiments showed that the proposed methodology performed pretty well achieving an overall accuracy close to 80%.

Nowadays, children, teens, and almost everyone around us tend to receive abundant and frequent advice regarding the usefulness of syllabification. Not only does it improve pronunciation, but it also makes it easier for us to read unfamiliar words in chunks of syllables rather than reading them all at once. Within this paper, we have designed, implemented, and presented a Turing machine-based syllable splitter. A Turing machine forms the theoretical basis for all modern computers and can be used to solve universal problems. On the other hand, a syllable splitter is used to hyphenate words into their corresponding syllables. We have proposed our work by illustrating the various states of the Turing machine, along with the rules it abides by, its machine specifications, and transition function. In addition to this, we have implemented a Graphical User Interface to stimulate our Turing machine to analyze our results better.

We study the problem of randomized Leader Election in synchronous distributed networks with indistinguishable nodes. We consider algorithms that work on networks of arbitrary topology in two settings, depending on whether the size of the network, i.e., the number of nodes \$n\$, is known or not. In the former setting, we present a new Leader Election protocol that improves over previous work by lowering message complexity and making it close to a lower bound by a factor in \$$\backslash$widetildeO($\backslash$sqrtt\_mix$\backslash$sqrt$\backslash$Phi)\$, where $\Phi$ is the conductance and \textsubscriptmix is the mixing time of the network graph. We then show that lacking the network size no Leader Election algorithm can guarantee that the election is final with constant probability, even with unbounded communication. Hence, we further classify the problem as Leader Election (the classic one, requiring knowledge of \$n\$ - as is our first protocol) or Revocable Leader Election, and present a new polynomial time and message complexity Revocable Leader Election algorithm in the setting without knowledge of network size. We analyze time and message complexity of our protocols in the CONGEST model of communication.

MANET stands for Mobile ad-hoc network, which is also known as a wireless network. It provides a routable networking environment which does not have a centralized infrastructure. MANET is used in many important sectors like economic sector (corporate field), security sector (military field), education sector (video conferences and lectures), law sector (law enforcement) and many more. Even though it plays a vital role in different sectors and improves its economic growth, security is a major concern in MANET. Due to lack of inbuilt security, several attacks like data traffic attack, control traffic attack. The wormhole is a kind of control traffic attack which forms wormhole link between nodes. In this paper, we have proposed an approach to detect and get rid of the wormhole attack. The proposed approach is based on trust values, which will decide whether nodes are affected by using parameters like receiving time and data rate. On evaluation, we have concluded that the wormhole attack decreases the network's performance while using trusted approach its value increases. Means PDR and throughput return best results for the affected network while in case of end to end delay it returns similar results as of unaffected network.

In some single-phase systems, power decoupling is necessary to balance the difference between constant power at load side and double-frequency ripple power at AC side. The application of active power decoupling methods aim to smooth this power oscillatory component, but, in general, these methods require the addition of many semiconductor devices and/or energy storage components, which is not lined up with achieving low cost, high efficiency and high power quality. This paper presents the analysis of a new single-phase rectifier based on zeta topology with power decoupling function and power factor correction using only two active switches and without extra reactive components. Its behavior is based on three stages of operation in a switching period, such that the power oscillating component is stored in one of the inherent zeta inductor. The theoretical foundation that justifies its operation is presented, as well as the simulation and experimental results to validate the applied concepts.

Protocol parsing is to discern and analyze packets' transmission fields, which plays an essential role in industrial security monitoring. The existing schemes parsing industrial protocols universally have problems, such as the limited parsing protocols, poor scalability, and high preliminary information requirements. This paper proposes a text similarity-based protocol parsing scheme (TPP) to identify and parse protocols for Industrial Internet of Things. TPP works in two stages, template generation and protocol parsing. In the template generation stage, TPP extracts protocol templates from protocol data packets by the cluster center extraction algorithm. The protocol templates will update continuously with the increase of the parsing packets' protocol types and quantities. In the protocol parsing phase, the protocol data packet will match the template according to the similarity measurement rules to identify and parse the fields of protocols. The similarity measurement method comprehensively measures the similarity between messages in terms of character position, sequence, and continuity to improve protocol parsing accuracy. We have implemented TPP in a smart industrial gateway and parsed more than 30 industrial protocols, including POWERLINK, DNP3, S7comm, Modbus-TCP, etc. We evaluate the performance of TPP by comparing it with the popular protocol analysis tool Netzob. The experimental results show that the accuracy of TPP is more than 20% higher than Netzob on average in industrial protocol identification and parsing.

Cyber attacks are becoming increasingly frequent, sophisticated, and stealthy. This makes it harder for cyber defence teams to keep up, forcing them to automate their defence capabilities in order to improve their reactivity and efficiency. Therefore, we propose a fully automated cyber defence framework that no longer needs support from humans to detect and mitigate attacks within a complex infrastructure. We design our framework based on a real-world case - Locked Shields - the world's largest cyber defence exercise. In this exercise, teams have to defend their networked infrastructure against attacks, while maintaining operational services for their users. Our framework architecture connects various cyber sensors with network, device, application, and user actuators through an artificial intelligence (AI)-powered automated team in order to dynamically secure the cyber environment. To the best of our knowledge, our framework is the first attempt towards a fully automated cyber defence team that aims at protecting complex environments from sophisticated attacks.

Cognitive Radio Networks (CRNs) promise efficient spectrum utilization by operating over the unused frequencies where Vehicular Ad-hoc Networks (VANETs) facilitate information exchanging among vehicles to avoid accidents, collisions, congestion, etc. Thus, CR enabled vehicular networks (CR-VANETs), a thriving area in wireless communication research, can be the enabler of Intelligent Transportation Systems (ITS) and autonomous driver-less vehicles. Similar to others, efficient and reliable communication in CR-VANETs is vital. Besides, security in such networks may exhibit unique characteristics for overall data transmission performance. For efficient and reliable communication, the proposed routing protocol considers the mobility patterns, spectrum availability, and trustworthiness to be the routing metrics. Hence, the protocol considers the vehicle's speed, mobility direction, inter-vehicles distance, and node's reliability to estimate the mobility patterns of a node. Besides, a trust-based reliability factor is also introduced to ensure secure communications by detecting malicious nodes or other external threats. Therefore, the proposed protocol detects malicious nodes by establishing trustworthiness among nodes and preserves security. Simulation is conducted for performance evaluation that shows the proposed routing selects the efficient routing path by discarding malicious nodes from the network and outperforms the existing routing protocols.

This paper presents a method optimizing the thrust force of a Micro Electro Mechanical System (MEMS) Permanent Magnet Linear Motor, based on harmonic current injection. Fourier decomposition is implemented to the air gap flux density of the motor to derive the fitting expression of the thrust force dependent to exciting current. Through analyzing the thrust force ripple of sinusoidal current excitement, the paper comes up with the strategy of harmonic current injection to eliminate the ripple component in the thrust force waveform. Mathematical demonstration is given that injecting harmonic current can totally eliminate the ripple caused by odd component of vertical air gap magnetic induction intensity. Simulation verification is implemented based on the 3rd and 7th harmonic injection control strategy, proving that the method is feasible for the thrust ripple is reduced to 4.3% of the value before optimazation. Experimental results lead to the consistent conclusion that the strategy shows good steady-state and dynamic performance.

Aiming at the problems of low accuracy and poor effect caused by the lack of data labels in most real network traffic, an optimized density peak clustering based on the improved salp swarm algorithm is proposed for traffic anomaly detection. Through the optimization of cosine decline and chaos strategy, the salp swarm algorithm not only accelerates the convergence speed, but also enhances the search ability. Moreover, we use the improved salp swarm algorithm to adaptively search the best truncation distance of density peak clustering, which avoids the subjectivity and uncertainty of manually selecting the parameters. The experimental results based on NSL-KDD dataset show that the improved salp swarm algorithm achieves faster convergence speed and higher precision, increases the average anomaly detection accuracy of 4.74% and detection rate of 6.14%, and reduces the average false positive rate of 7.38%.

This paper introduces a scheme for achieving trustworthy computing on SoCs that use an outsourced AXI interconnect for on-chip communication. This is achieved through component guarding, data tagging, event verification, and consequently responding dynamically to an attack. Experimental results confirm the ability of the proposed scheme to detect HT attacks and respond to them at run-time. The proposed scheme extends the state-of-art in trustworthy computing on untrustworthy components by focusing on the issue of an untrusted on-chip interconnect for the first time, and by developing a scheme that is independent of untrusted third-party IP.