Biblio
In recent years, prodigious explosion of social network services may trigger new business models. However, it has negative aspects such as personal information spill or spamming, as well. Amongst conventional spam detection approaches, the studies which are based on vertex degrees or Local Clustering Coefficient have been caused false positive results so that normal vertices can be specified as spammers. In this paper, we propose a novel approach by employing the circuit structure in the social networks, which demonstrates the advantages of our work through the experiment.
Transformations form an important part of developing domain specific languages, where they are used to provide semantics for typing and evaluation. Yet, few solutions exist for verifying transformations written in expressive high-level transformation languages. We take a step towards that goal, by developing a general symbolic execution technique that handles programs written in these high-level transformation languages. We use logical constraints to describe structured symbolic values, including containment, acyclicity, simple unordered collections (sets) and to handle deep type-based querying of syntax hierarchies. We evaluate this symbolic execution technique on a collection of refactoring and model transformation programs, showing that the white-box test generation tool based on symbolic execution obtains better code coverage than a black box test generator for such programs in almost all tested cases.
Recent incidents have once again brought the topic of encryption to public discourse, while researchers continue to demonstrate attacks that highlight the difficulty of implementing encryption even without the presence of "backdoors". However, apart from the threat of implementation flaws in encryption libraries, another significant threat arises when web services fail to enforce ubiquitous encryption. A recent study explored this phenomenon in popular services, and demonstrated how users are exposed to cookie hijacking attacks with severe privacy implications. Many security mechanisms purport to eliminate this problem, ranging from server-controlled options such as HSTS to user-controlled options such as HTTPS Everywhere and other browser extensions. In this paper, we create a taxonomy of available mechanisms and evaluate how they perform in practice. We design an automated testing framework for these mechanisms, and evaluate them using a dataset of 30 days of HTTP requests collected from the public wireless network of our university's campus. We find that all mechanisms suffer from implementation flaws or deployment issues and argue that, as long as servers continue to not support ubiquitous encryption across their entire domain (including all subdomains), no mechanism can effectively protect users from cookie hijacking and information leakage.
The image and multimedia data produced by individuals and enterprises is increasing every day. Motivated by the advances in cloud computing, there is a growing need to outsource such computational intensive image feature detection tasks to cloud for its economic computing resources and on-demand ubiquitous access. However, the concerns over the effective protection of private image and multimedia data when outsourcing it to cloud platform become the major barrier that impedes the further implementation of cloud computing techniques over massive amount of image and multimedia data. To address this fundamental challenge, we study the state-of-the-art image feature detection algorithms and focus on Scalar Invariant Feature Transform (SIFT), which is one of the most important local feature detection algorithms and has been broadly employed in different areas, including object recognition, image matching, robotic mapping, and so on. We analyze and model the privacy requirements in outsourcing SIFT computation and propose Secure Scalar Invariant Feature Transform (SecSIFT), a high-performance privacy-preserving SIFT feature detection system. In contrast to previous works, the proposed design is not restricted by the efficiency limitations of current homomorphic encryption scheme. In our design, we decompose and distribute the computation procedures of the original SIFT algorithm to a set of independent, co-operative cloud servers and keep the outsourced computation procedures as simple as possible to avoid utilizing a computationally expensive homomorphic encryption scheme. The proposed SecSIFT enables implementation with practical computation and communication complexity. Extensive experimental results demonstrate that SecSIFT performs comparably to original SIFT on image benchmarks while capable of preserving the privacy in an efficient way.
With the advent of social networks and cloud computing, the amount of multimedia data produced and communicated within social networks is rapidly increasing. In the meantime, social networking platforms based on cloud computing have made multimedia big data sharing in social networks easier and more efficient. The growth of social multimedia, as demonstrated by social networking sites such as Facebook and YouTube, combined with advances in multimedia content analysis, underscores potential risks for malicious use, such as illegal copying, piracy, plagiarism, and misappropriation. Therefore, secure multimedia sharing and traitor tracing issues have become critical and urgent in social networks. In this article, a joint fingerprinting and encryption (JFE) scheme based on tree-structured Haar wavelet transform (TSHWT) is proposed with the purpose of protecting media distribution in social network environments. The motivation is to map hierarchical community structure of social networks into a tree structure of Haar wavelet transform for fingerprinting and encryption. First, fingerprint code is produced using social network analysis (SNA). Second, the content is decomposed based on the structure of fingerprint code by the TSHWT. Then, the content is fingerprinted and encrypted in the TSHWT domain. Finally, the encrypted contents are delivered to users via hybrid multicast-unicast. The proposed method, to the best of our knowledge, is the first scalable JFE method for fingerprinting and encryption in the TSHWT domain using SNA. The use of fingerprinting along with encryption using SNA not only provides a double layer of protection for social multimedia sharing in social network environment but also avoids big data superposition effect. Theory analysis and experimental results show the effectiveness of the proposed JFE scheme.
Cyber-attacks are cheap, easy to conduct and often pose little risk in terms of attribution, but their impact could be lasting. The low attribution is because tracing cyber-attacks is primitive in the current network architecture. Moreover, even when attribution is known, the absence of enforcement provisions in international law makes cyber attacks tough to litigate, and hence attribution is hardly a deterrent. Rather than attributing attacks, we can re-look at cyber-attacks as societal events associated with social, political, economic and cultural (SPEC) motivations. Because it is possible to observe SPEC motives on the internet, social media data could be valuable in understanding cyber attacks. In this research, we use sentiment in Twitter posts to observe country-to-country perceptions, and Arbor Networks data to build ground truth of country-to-country DDoS cyber-attacks. Using this dataset, this research makes three important contributions: a) We evaluate the impact of heightened sentiments towards a country on the trend of cyber-attacks received by the country. We find that, for some countries, the probability of attacks increases by up to 27% while experiencing negative sentiments from other nations. b) Using cyber-attacks trend and sentiments trend, we build a decision tree model to find attacks that could be related to extreme sentiments. c) To verify our model, we describe three examples in which cyber-attacks follow increased tension between nations, as perceived in social media.
The extremely rapid development of the Internet of Things brings growing attention to the information security issue. Realization of cryptographically strong pseudo random number generators (PRNGs), is crucial in securing sensitive data. They play an important role in cryptography and in network security applications. In this paper, we realize a comparative study of two pseudo chaotic number generators (PCNGs). The First pseudo chaotic number generator (PCNG1) is based on two nonlinear recursive filters of order one using a Skew Tent map (STmap) and a Piece-Wise Linear Chaotic map (PWLCmap) as non linear functions. The second pseudo chaotic number generator (PCNG2) consists of four coupled chaotic maps, namely: PWLCmaps, STmap, Logistic map by means a binary diffusion matrix [D]. A comparative analysis of the performance in terms of computation time (Generation time, Bit rate and Number of needed cycles to generate one byte) and security of the two PCNGs is carried out.
In this paper, we introduce an optical network with cross-layer security, which can enhance security performance. In the transmitter, the user's data is encrypted at first. After that, based on optical encoding, physical layer encryption is implemented. In the receiver, after the corresponding optical decoding process, decryption algorithm is used to restore user's data. In this paper, the security performance has been evaluated quantitatively.
The serializability of transactions is the most important property that ensure correct processing to transactions. In case of concurrent access to the same data by several transactions, or in case of dependency relationships between running sub transactions. But some transactions has been marked as malicious and they compromise the serialization of running system. For that purpose, we propose an intrusion tolerant scheme to ensure the continuity of the running transactions. A transaction dependency graph is also used by the CDC to make decisions concerning the set of data and transactions that are threatened by a malicious activity. We will give explanations about how to use the proposed scheme to illustrate its behavior and efficiency against a compromised transaction-based in a cloud of databases environment. Several issues should be considered when dealing with the processing of a set of interleaved transactions in a transaction based environment. In most cases, these issues are due to the concurrent access to the same data by several transactions or the dependency relationship between running transactions. The serializability may be affected if a transaction that belongs to the processing node is compromised.
This article deals with the estimation of magnet losses in a permanent-magnet motor inserted in a nut-runner. This type of machine has interesting features such as being two-pole, slot-less and running at a high speed (30000 rpm). Two analytical models were chosen from the literature. A numerical estimation of the losses with 2D Finite Element Method was carried out. A detailed investigation of the effect of simulation settings (e.g., mesh size, time-step, remanence flux density in the magnet, superposition of the losses, etc.) was performed. Finally, calculation of losses with 3D-FEM were also run in order to compare the calculated losses with both analytical and 2D-FEM results. The estimation of the losses focuses on a range of frequencies between 10 and 100 kHz.
Information Centric Networking (ICN) paradigms nicely fit the world of wireless sensors, whose devices have tight constraints. In this poster, we compare two alternative designs for secure association of new IoT devices in existing ICN deployments, which are based on asymmetric and symmetric cryptography respectively. While the security properties of both approaches are equivalent, an interesting trade-off arises between properties of the protocol vs properties of its implementation in current IoT boards. Indeed, while the asymmetric-keys based approach incurs a lower traffic overhead (of about 30%), we find that its implementation is significantly more energy- and time-consuming due to the cost of cryptographic operations (it requires up to 41x more energy and 8x more time).
The demand for trained cybersecurity operators is growing more quickly than traditional programs in higher education can fill. At the same time, unemployment for returning military veterans has become a nationally discussed problem. We describe the design and launch of New Skills for a New Fight (NSNF), an intensive, one-year program to train military veterans for the cybersecurity field. This non-traditional program, which leverages experience that veterans gained in military service, includes recruitment and selection, a base of knowledge in the form of four university courses in a simultaneous cohort mode, a period of hands-on cybersecurity training, industry certifications and a practical internship in a Security Operations Center (SOC). Twenty veterans entered this pilot program in January of 2016, and will complete in less than a year's time. Initially funded by a global financial services company, the program provides veterans with an expense-free preparation for an entry-level cybersecurity job.
Information-Centric Networking (ICN) is an emerging networking paradigm that focuses on content distribution and aims at replacing the current IP stack. Implementations of ICN have demonstrated its advantages over IP, in terms of network performance and resource requirements. Because of these advantages, ICN is also considered to be a good network paradigm candidate for the Internet-of-Things (IoT), especially in scenarios involving resource constrained devices. In this paper we propose OnboardICNg, the first secure protocol for on-boarding (authenticating and authorizing) IoT devices in ICN mesh networks. OnboardICNg can securely onboard resource constrained devices into an existing IoT network, outperforming the authentication protocol selected for the ZigBee-IP specification: EAP-PANA, i.e., the Protocol for carrying Authentication for Network Access (PANA) combined with the Extensible Authentication Protocol (EAP). In particular we show that, compared with EAP-PANA, OnboardICNg reduces the communication and energy consumption, by 87% and 66%, respectively.
Recent years have witnessed a flourish of hands-on cybersecurity labs and competitions. The information technology (IT) education community has recognized their significant role in boosting students' interest in security and enhancing their security knowledge and skills. Compared to the focus on individual based education materials, much less attention has been paid to the development of tools and materials suitable for team-based security practices, which, however, prevail in real-world environments. One major bottleneck is lack of suitable platforms for this type of practices in IT education community. In this paper, we propose a low-cost, team-oriented cybersecurity practice platform called Platoon. The Platoon platform allows for quickly and automatically creating one or more virtual networks that mimic real-world corporate networks using a regular computer. The virtual environment created by Platoon is suitable for both cybersecurity labs, competitions, and projects. The performance data and user feedback collected from our cyber-defense exercises indicate that Platoon is practical and useful for enhancing students' security learning outcomes.
Friends, family and colleagues at work may repeatedly observe how their peers unlock their smartphones. These "insiders" may combine multiple partial observations to form a hypothesis of a target's secret. This changing landscape requires that we update the methods used to assess the security of unlocking mechanisms against human shoulder surfing attacks. In our paper, we introduce a methodology to study shoulder surfing risks in the insider threat model. Our methodology dissects the authentication process into minimal observations by humans. Further processing is based on simulations. The outcome is an estimate of the number of observations needed to break a mechanism. The flexibility of this approach benefits the design of new mechanisms. We demonstrate the application of our methodology by performing an analysis of the SwiPIN scheme published at CHI 2015. Our results indicate that SwiPIN can be defeated reliably by a majority of the population with as few as 6 to 11 observations.
While the potential advantages of geographic forwarding in wireless sensor networks (WSN) have been demonstrated for a while now, research in applying Information Centric Networking (ICN) has only gained momentum in the last few years. In this paper, we bridge these two worlds by proposing an ICN-compliant and secure implementation of geographic forwarding for ICN. We implement as a proof of concept the Greedy Perimeter Stateless Routing (GPSR) algorithm and compare its performance to that of vanilla ICN forwarding. We also evaluate the cost of security in 802.15.4 networks in terms of energy, memory and CPU footprint. We show that in sparse but large networks, GPSR outperforms vanilla ICN forwarding in both memory footprint and CPU consumption. However, GPSR is more energy intensive because of the cost of communications.
Technological changes bring great efficiencies and opportunities; however, they also bring new threats and dangers that users are often ill prepared to handle. Some individuals have training at work or school while others have family or friends to help them. However, there are few widely known or ubiquitous educational programs to inform and motivate users to develop safe cybersecurity practices. Additionally, little is known about learning strategies in this domain. Understanding how active Internet users have learned their security practices can give insight into more effective learning methods. I surveyed 800 online labor workers to discover their learning processes. They shared how they had to construct their own schema and negotiate meaning in a complex domain. Findings suggest a need to help users build a dynamic mental model of security. Participants recommend encouraging participatory and constructive learning, multi-model dissemination, and ubiquitous opportunities for learning security behaviors.
This panel will discuss and debate what role(s) the information technology discipline should have in cybersecurity. Diverse viewpoints will be considered including current and potential ACM curricular recommendations, current and potential ABET and NSA accreditation criteria, the emerging cybersecurity discipline(s), consideration of government frameworks, the need for a multi-disciplinary approach to cybersecurity, and what aspects of cybersecurity should be under information technology's purview.
Syntax extension mechanisms are powerful, but reasoning about syntax extensions can be difficult. Recent work on type-specific languages (TSLs) addressed reasoning about composition, hygiene and typing for extensions introducing new literal forms. We supplement TSLs with typed syntax macros (TSMs), which, unlike TSLs, are explicitly invoked to give meaning to delimited segments of arbitrary syntax. To maintain a typing discipline, we describe two avors of term-level TSMs: synthetic TSMs specify the type of term that they generate, while analytic TSMs can generate terms of arbitrary type, but can only be used in positions where the type is otherwise known. At the level of types, we describe a third avor of TSM that generates a type of a specified kind along with its TSL and show interesting use cases where the two mechanisms operate in concert.
A3 is an execution management environment that aims to make network-facing applications and services resilient against zero-day attacks. A3 recently underwent two adversarial evaluations of its defensive capabilities. In one, A3 defended an App Store used in a Capture the Flag (CTF) tournament, and in the other, a tactically relevant network service in a red team exercise. This paper describes the A3 defensive technologies evaluated, the evaluation results, and the broader lessons learned about evaluations for technologies that seek to protect critical systems from zero-day attacks.
The smart grid changes the way energy is produced and distributed. In addition both, energy and information is exchanged bidirectionally among participating parties. Therefore heterogeneous systems have to cooperate effectively in order to achieve a common high-level use case, such as smart metering for billing or demand response for load curtailment. Furthermore, a substantial amount of personal data is often needed for achieving that goal. Capturing and processing personal data in the smart grid increases customer concerns about privacy and in addition, certain statutory and operational requirements regarding privacy aware data processing and storage have to be met. An increase of privacy constraints, however, often limits the operational capabilities of the system. In this paper, we present an approach that automates the process of finding an optimal balance between privacy requirements and operational requirements in a smart grid use case and application scenario. This is achieved by formally describing use cases in an abstract model and by finding an algorithm that determines the optimum balance by forward mapping privacy and operational impacts. For this optimal balancing algorithm both, a numeric approximation and - if feasible - an analytic assessment are presented and investigated. The system is evaluated by applying the tool to a real-world use case from the University of Southern California (USC) microgrid.
This article proposes Probabilistic Replacement Policy (PRP), a novel replacement policy that evicts the line with minimum estimated hit probability under optimal replacement instead of the line with maximum expected reuse distance. The latter is optimal under the independent reference model of programs, which does not hold for last-level caches (LLC). PRP requires 7% and 2% metadata overheads in the cache and DRAM respectively. Using a sampling scheme makes DRAM overhead negligible, with minimal performance impact. Including detailed overhead modeling and equal cache areas, PRP outperforms SHiP, a state-of-the-art LLC replacement algorithm, by 4% for memory-intensive SPEC-CPU2006 benchmarks.