Biblio

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2018-04-11
Cornell, N., Nepal, K..  2017.  Combinational Hardware Trojan Detection Using Logic Implications. 2017 IEEE 60th International Midwest Symposium on Circuits and Systems (MWSCAS). :571–574.

This paper provides a proof-of-concept demonstration of the potential benefit of using logical implications for detection of combinational hardware trojans. Using logic simulation, valid logic implications are selected and added to to the checker circuitry to detect payload delivery by a combinational hardware trojan. Using combinational circuits from the ISCAS benchmark suite, and a modest hardware budget for the checker, simulation results show that the probability of a trojan escaping detection using our approach was only 16%.

2017-12-20
Rubin, S. H., Grefe, W. K., Bouabana-Tebibel, T., Chen, S. C., Shyu, M. L., Simonsen, K. S..  2017.  Cyber-Secure UAV Communications Using Heuristically Inferred Stochastic Grammars and Hard Real-Time Adaptive Waveform Synthesis and Evolution. 2017 IEEE International Conference on Information Reuse and Integration (IRI). :9–15.
Summary form only given. Strong light-matter coupling has been recently successfully explored in the GHz and THz [1] range with on-chip platforms. New and intriguing quantum optical phenomena have been predicted in the ultrastrong coupling regime [2], when the coupling strength Ω becomes comparable to the unperturbed frequency of the system ω. We recently proposed a new experimental platform where we couple the inter-Landau level transition of an high-mobility 2DEG to the highly subwavelength photonic mode of an LC meta-atom [3] showing very large Ω/ωc = 0.87. Our system benefits from the collective enhancement of the light-matter coupling which comes from the scaling of the coupling Ω ∝ √n, were n is the number of optically active electrons. In our previous experiments [3] and in literature [4] this number varies from 104-103 electrons per meta-atom. We now engineer a new cavity, resonant at 290 GHz, with an extremely reduced effective mode surface Seff = 4 × 10-14 m2 (FE simulations, CST), yielding large field enhancements above 1500 and allowing to enter the few (\textbackslashtextless;100) electron regime. It consist of a complementary metasurface with two very sharp metallic tips separated by a 60 nm gap (Fig.1(a, b)) on top of a single triangular quantum well. THz-TDS transmission experiments as a function of the applied magnetic field reveal strong anticrossing of the cavity mode with linear cyclotron dispersion. Measurements for arrays of only 12 cavities are reported in Fig.1(c). On the top horizontal axis we report the number of electrons occupying the topmost Landau level as a function of the magnetic field. At the anticrossing field of B=0.73 T we measure approximately 60 electrons ultra strongly coupled (Ω/ω- \textbackslashtextbar\textbackslashtextbar
2018-02-28
Cheval, V., Cortier, V., Warinschi, B..  2017.  Secure Composition of PKIs with Public Key Protocols. 2017 IEEE 30th Computer Security Foundations Symposium (CSF). :144–158.

We use symbolic formal models to study the composition of public key-based protocols with public key infrastructures (PKIs). We put forth a minimal set of requirements which a PKI should satisfy and then identify several reasons why composition may fail. Our main results are positive and offer various trade-offs which align the guarantees provided by the PKI with those required by the analysis of protocol with which they are composed. We consider both the case of ideally distributed keys but also the case of more realistic PKIs.,,Our theorems are broadly applicable. Protocols are not limited to specific primitives and compositionality asks only for minimal requirements on shared ones. Secure composition holds with respect to arbitrary trace properties that can be specified within a reasonably powerful logic. For instance, secrecy and various forms of authentication can be expressed in this logic. Finally, our results alleviate the common yet demanding assumption that protocols are fully tagged.

2017-12-12
Massonet, P., Deru, L., Achour, A., Dupont, S., Croisez, L. M., Levin, A., Villari, M..  2017.  Security in Lightweight Network Function Virtualisation for Federated Cloud and IoT. 2017 IEEE 5th International Conference on Future Internet of Things and Cloud (FiCloud). :148–154.

Smart IoT applications require connecting multiple IoT devices and networks with multiple services running in fog and cloud computing platforms. One approach to connecting IoT devices with cloud and fog services is to create a federated virtual network. The main benefit of this approach is that IoT devices can then interact with multiple remote services using an application specific federated network where no traffic from other applications passes. This federated network spans multiple cloud platforms and IoT networks but it can be managed as a single entity. From the point of view of security, federated virtual networks can be managed centrally and be secured with a coherent global network security policy. This does not mean that the same security policy applies everywhere, but that the different security policies are specified in a single coherent security policy. In this paper we propose to extend a federated cloud networking security architecture so that it can secure IoT devices and networks. The federated network is extended to the edge of IoT networks by integrating a federation agent in an IoT gateway or network controller (Can bus, 6LowPan, Lora, ...). This allows communication between the federated cloud network and the IoT network. The security architecture is based on the concepts of network function virtualisation (NFV) and service function chaining (SFC) for composing security services. The IoT network and devices can then be protected by security virtual network functions (VNF) running at the edge of the IoT network.

2018-10-26
Tiwari, V., Chaurasia, B. K..  2017.  Security issues in fog computing using vehicular cloud. 2017 International Conference on Information, Communication, Instrumentation and Control (ICICIC). :1–4.

In the near future, vehicular cloud will help to improve traffic safety and efficiency. Unfortunately, a computing of vehicular cloud and fog cloud faced a set of challenges in security, authentication, privacy, confidentiality and detection of misbehaving vehicles. In addition to, there is a need to recognize false messages from received messages in VANETs during moving on the road. In this work, the security issues and challenges for computing in the vehicular cloud over for computing is studied.

2017-12-20
Chen, C. K., Lan, S. C., Shieh, S. W..  2017.  Shellcode detector for malicious document hunting. 2017 IEEE Conference on Dependable and Secure Computing. :527–528.

Advanced Persistent Threat (APT) attacks became a major network threat in recent years. Among APT attack techniques, sending a phishing email with malicious documents attached is considered one of the most effective ones. Although many users have the impression that documents are harmless, a malicious document may in fact contain shellcode to attack victims. To cope with the problem, we design and implement a malicious document detector called Forensor to differentiate malicious documents. Forensor integrates several open-source tools and methods. It first introspects file format to retrieve objects inside the documents, and then automatically decrypts simple encryption methods, e.g., XOR, rot and shift, commonly used in malware to discover potential shellcode. The emulator is used to verify the presence of shellcode. If shellcode is discovered, the file is considered malicious. The experiment used 9,000 benign files and more than 10,000 malware samples from a well-known sample sharing website. The result shows no false negative and only 2 false positives.

2018-02-06
Tchernykh, A., Babenko, M., Chervyakov, N., Cortés-Mendoza, J. M., Kucherov, N., Miranda-López, V., Deryabin, M., Dvoryaninova, I., Radchenko, G..  2017.  Towards Mitigating Uncertainty of Data Security Breaches and Collusion in Cloud Computing. 2017 28th International Workshop on Database and Expert Systems Applications (DEXA). :137–141.

Cloud computing has become a part of people's lives. However, there are many unresolved problems with security of this technology. According to the assessment of international experts in the field of security, there are risks in the appearance of cloud collusion in uncertain conditions. To mitigate this type of uncertainty, and minimize data redundancy of encryption together with harms caused by cloud collusion, modified threshold Asmuth-Bloom and weighted Mignotte secret sharing schemes are used. We show that if the villains do know the secret parts, and/or do not know the secret key, they cannot recuperate the secret. If the attackers do not know the required number of secret parts but know the secret key, the probability that they obtain the secret depends the size of the machine word in bits that is less than 1/2(1-1). We demonstrate that the proposed scheme ensures security under several types of attacks. We propose four approaches to select weights for secret sharing schemes to optimize the system behavior based on data access speed: pessimistic, balanced, and optimistic, and on speed per price ratio. We use the approximate method to improve the detection, localization and error correction accuracy under cloud parameters uncertainty.

2018-01-23
Acar, A., Celik, Z. B., Aksu, H., Uluagac, A. S., McDaniel, P..  2017.  Achieving Secure and Differentially Private Computations in Multiparty Settings. 2017 IEEE Symposium on Privacy-Aware Computing (PAC). :49–59.

Sharing and working on sensitive data in distributed settings from healthcare to finance is a major challenge due to security and privacy concerns. Secure multiparty computation (SMC) is a viable panacea for this, allowing distributed parties to make computations while the parties learn nothing about their data, but the final result. Although SMC is instrumental in such distributed settings, it does not provide any guarantees not to leak any information about individuals to adversaries. Differential privacy (DP) can be utilized to address this; however, achieving SMC with DP is not a trivial task, either. In this paper, we propose a novel Secure Multiparty Distributed Differentially Private (SM-DDP) protocol to achieve secure and private computations in a multiparty environment. Specifically, with our protocol, we simultaneously achieve SMC and DP in distributed settings focusing on linear regression on horizontally distributed data. That is, parties do not see each others’ data and further, can not infer information about individuals from the final constructed statistical model. Any statistical model function that allows independent calculation of local statistics can be computed through our protocol. The protocol implements homomorphic encryption for SMC and functional mechanism for DP to achieve the desired security and privacy guarantees. In this work, we first introduce the theoretical foundation for the SM-DDP protocol and then evaluate its efficacy and performance on two different datasets. Our results show that one can achieve individual-level privacy through the proposed protocol with distributed DP, which is independently applied by each party in a distributed fashion. Moreover, our results also show that the SM-DDP protocol incurs minimal computational overhead, is scalable, and provides security and privacy guarantees.

2017-12-28
Shih, M. H., Chang, J. M..  2017.  Design and analysis of high performance crypt-NoSQL. 2017 IEEE Conference on Dependable and Secure Computing. :52–59.

NoSQL databases have become popular with enterprises due to their scalable and flexible storage management of big data. Nevertheless, their popularity also brings up security concerns. Most NoSQL databases lacked secure data encryption, relying on developers to implement cryptographic methods at application level or middleware layer as a wrapper around the database. While this approach protects the integrity of data, it increases the difficulty of executing queries. We were motivated to design a system that not only provides NoSQL databases with the necessary data security, but also supports the execution of query over encrypted data. Furthermore, how to exploit the distributed fashion of NoSQL databases to deliver high performance and scalability with massive client accesses is another important challenge. In this research, we introduce Crypt-NoSQL, the first prototype to support execution of query over encrypted data on NoSQL databases with high performance. Three different models of Crypt-NoSQL were proposed and performance was evaluated with Yahoo! Cloud Service Benchmark (YCSB) considering an enormous number of clients. Our experimental results show that Crypt-NoSQL can process queries over encrypted data with high performance and scalability. A guidance of establishing service level agreement (SLA) for Crypt-NoSQL as a cloud service is also proposed.

2018-02-21
Zhang, X., Cao, Y., Yang, M., Wu, J., Luo, T., Liu, Y..  2017.  Droidrevealer: Automatically detecting Mysterious Codes in Android applications. 2017 IEEE Conference on Dependable and Secure Computing. :535–536.

The state-of-the-art Android malware often encrypts or encodes malicious code snippets to evade malware detection. In this paper, such undetectable codes are called Mysterious Codes. To make such codes detectable, we design a system called Droidrevealer to automatically identify Mysterious Codes and then decode or decrypt them. The prototype of Droidrevealer is implemented and evaluated with 5,600 malwares. The results show that 257 samples contain the Mysterious Codes and 11,367 items are exposed. Furthermore, several sensitive behaviors hidden in the Mysterious Codes are disclosed by Droidrevealer.

2017-12-20
Comon, H., Koutsos, A..  2017.  Formal Computational Unlinkability Proofs of RFID Protocols. 2017 IEEE 30th Computer Security Foundations Symposium (CSF). :100–114.

We set up a framework for the formal proofs of RFID protocols in the computational model. We rely on the so-called computationally complete symbolic attacker model. Our contributions are: 1) to design (and prove sound) axioms reflecting the properties of hash functions (Collision-Resistance, PRF). 2) to formalize computational unlinkability in the model. 3) to illustrate the method, providing the first formal proofs of unlinkability of RFID protocols, in the omputational model.

2018-06-20
Lee, Y., Choi, S. S., Choi, J., Song, J..  2017.  A Lightweight Malware Classification Method Based on Detection Results of Anti-Virus Software. 2017 12th Asia Joint Conference on Information Security (AsiaJCIS). :5–9.

With the development of cyber threats on the Internet, the number of malware, especially unknown malware, is also dramatically increasing. Since all of malware cannot be analyzed by analysts, it is very important to find out new malware that should be analyzed by them. In order to cope with this issue, the existing approaches focused on malware classification using static or dynamic analysis results of malware. However, the static and the dynamic analyses themselves are also too costly and not easy to build the isolated, secure and Internet-like analysis environments such as sandbox. In this paper, we propose a lightweight malware classification method based on detection results of anti-virus software. Since the proposed method can reduce the volume of malware that should be analyzed by analysts, it can be used as a preprocess for in-depth analysis of malware. The experimental showed that the proposed method succeeded in classification of 1,000 malware samples into 187 unique groups. This means that 81% of the original malware samples do not need to analyze by analysts.

2017-12-27
Pich, R., Chivapreecha, S., Prabnasak, J..  2017.  A new key generator for data encryption using chaos in digital filter. 2017 IEEE 8th Control and System Graduate Research Colloquium (ICSGRC). :87–92.

The presented work of this paper is to propose the implementation of chaotic crypto-system with the new key generator using chaos in digital filter for data encryption and decryption. The chaos in digital filter of the second order system is produced by the coefficients which are initialed in the key generator to produce other new coefficients. Private key system using the initial coefficients value condition and dynamic input as password of 16 characters is to generate the coefficients for crypto-system. In addition, we have tension specifically to propose the solution of data security in lightweight cryptography based on external and internal key in which conducts with the appropriate key sensitivity plus high performance. The chaos in digital filter has functioned as the main major in the system. The experimental results illustrate that the proposed data encryption with new key generator system is the high sensitive system with accuracy key test 99% and can make data more secure with high performance.

2018-01-10
Frumento, Enrico, Freschi, Federica, Andreoletti, Davide, Consoli, Angelo.  2017.  Victim Communication Stack (VCS): A Flexible Model to Select the Human Attack Vector. Proceedings of the 12th International Conference on Availability, Reliability and Security. :50:1–50:6.
Information security has rapidly grown to meet the requirements of today services. A solid discipline has been developed as far as technical security is concerned. However, the human layer plays an increasingly decisive role in the managing of Information Technology (IT) systems. The research field that studies the vulnerabilities of the human layer is referred to as Social Engineering, and has not received the same attention of its technical counterpart. We try to partially fill this gap by studying the selection of the Human Attack Vector (HAV), i.e., the path or the means that the attacker uses to compromise the human layer. To this aim, we propose a multilayer model, named Victim Communication Stack (VCS), that provides the key elements to facilitate the choice of the HAV. This work has been carried out under the DOGANA European project.
2018-05-25
2018-05-09
Lu, Z., Chen, F., Cheng, G., Ai, J..  2017.  A secure control plane for SDN based on Bayesian Stackelberg Games. 2017 3rd IEEE International Conference on Computer and Communications (ICCC). :1259–1264.

Vulnerabilities of controller that is caused by separation of control and forwarding lead to a threat which attacker can take remote access detection in SDN. The current work proposes a controller architecture called secure control plane (SCP) that enhances security and increase the difficulty of the attack through a rotation of heterogeneous and multiple controllers. Specifically, a dynamic-scheduling method based on Bayesian Stackelberg Games is put forward to maximize security reward of defender during each migration. Secondly, introducing a self-cleaning mechanism combined with game strategy aims at improving the secure level and form a closed-loop defense mechanism; Finally, the experiments described quantitatively defender will get more secure gain based on the game strategy compared with traditional strategy (pure and random strategies), and the self-cleaning mechanism can make the control plane to be in a higher level of security.

2018-02-21
Shajaiah, H., Abdelhadi, A., Clancy, C..  2017.  Secure power scheduling auction for smart grids using homomorphic encryption. 2017 IEEE International Conference on Big Data (Big Data). :4507–4512.

In this paper, we introduce a secure energy trading auction approach to schedule the power plant limited resources during peak hours time slots. In the proposed auction model, the power plant serving a power grid shares with the smart meters its available amount of resources that is expected during the next future peak time slot; smart meters expecting a demand for additional power participate in the power auction by submitting bids of their offered price for their requested amount of power. In order to secure the power auction and protect smart meters' privacy, homomorphic encryption through Paillier cryptosystem is used to secure the bidding values and ensure avoiding possible insincere behaviors of smart meters or the grid operator (i.e. the auctioneer) to manipulate the auction for their own benefits. In addition, we use a payment rule that maximizes the power plant's revenue. We propose an efficient power scheduling mechanism to distribute the operator's limited resources among smart meters participating in the power auction. Finally, we present simulation results for the performance of our secure power scheduling auction mechanism.

2018-03-19
Showkatbakhsh, M., Shoukry, Y., Chen, R. H., Diggavi, S., Tabuada, P..  2017.  An SMT-Based Approach to Secure State Estimation under Sensor and Actuator Attacks. 2017 IEEE 56th Annual Conference on Decision and Control (CDC). :157–162.

This paper addresses the problem of state estimation of a linear time-invariant system when some of the sensors or/and actuators are under adversarial attack. In our set-up, the adversarial agent attacks a sensor (actuator) by manipulating its measurement (input), and we impose no constraint on how the measurements (inputs) are corrupted. We introduce the notion of ``sparse strong observability'' to characterize systems for which the state estimation is possible, given bounds on the number of attacked sensors and actuators. Furthermore, we develop a secure state estimator based on Satisfiability Modulo Theory (SMT) solvers.

2018-04-11
Ghanem, K., Aparicio-Navarro, F. J., Kyriakopoulos, K. G., Lambotharan, S., Chambers, J. A..  2017.  Support Vector Machine for Network Intrusion and Cyber-Attack Detection. 2017 Sensor Signal Processing for Defence Conference (SSPD). :1–5.

Cyber-security threats are a growing concern in networked environments. The development of Intrusion Detection Systems (IDSs) is fundamental in order to provide extra level of security. We have developed an unsupervised anomaly-based IDS that uses statistical techniques to conduct the detection process. Despite providing many advantages, anomaly-based IDSs tend to generate a high number of false alarms. Machine Learning (ML) techniques have gained wide interest in tasks of intrusion detection. In this work, Support Vector Machine (SVM) is deemed as an ML technique that could complement the performance of our IDS, providing a second line of detection to reduce the number of false alarms, or as an alternative detection technique. We assess the performance of our IDS against one-class and two-class SVMs, using linear and non- linear forms. The results that we present show that linear two-class SVM generates highly accurate results, and the accuracy of the linear one-class SVM is very comparable, and it does not need training datasets associated with malicious data. Similarly, the results evidence that our IDS could benefit from the use of ML techniques to increase its accuracy when analysing datasets comprising of non- homogeneous features.

2018-06-11
Wu, D., Xu, Z., Chen, B., Zhang, Y..  2017.  Towards Access Control for Network Coding-Based Named Data Networking. GLOBECOM 2017 - 2017 IEEE Global Communications Conference. :1–6.

Named Data Networking (NDN) is a content-oriented future Internet architecture, which well suits the increasingly mobile and information-intensive applications that dominate today's Internet. NDN relies on in-network caching to facilitate content delivery. This makes it challenging to enforce access control since the content has been cached in the routers and the content producer has lost the control over it. Due to its salient advantages in content delivery, network coding has been introduced into NDN to improve content delivery effectiveness. In this paper, we design ACNC, the first Access Control solution specifically for Network Coding-based NDN. By combining a novel linear AONT (All Or Nothing Transform) and encryption, we can ensure that only the legitimate user who possesses the authorization key can successfully recover the encoding matrix for network coding, and hence can recover the content being transmitted. In addition, our design has two salient merits: 1) the linear AONT well suits the linear nature of network coding; 2) only one vector of the encoding matrix needs to be encrypted/decrypted, which only incurs small computational overhead. Security analysis and experimental evaluation in ndnSIM show that our design can successfully enforce access control on network coding-based NDN with an acceptable overhead.

2018-02-06
Tiwari, T., Turk, A., Oprea, A., Olcoz, K., Coskun, A. K..  2017.  User-Profile-Based Analytics for Detecting Cloud Security Breaches. 2017 IEEE International Conference on Big Data (Big Data). :4529–4535.

While the growth of cloud-based technologies has benefited the society tremendously, it has also increased the surface area for cyber attacks. Given that cloud services are prevalent today, it is critical to devise systems that detect intrusions. One form of security breach in the cloud is when cyber-criminals compromise Virtual Machines (VMs) of unwitting users and, then, utilize user resources to run time-consuming, malicious, or illegal applications for their own benefit. This work proposes a method to detect unusual resource usage trends and alert the user and the administrator in real time. We experiment with three categories of methods: simple statistical techniques, unsupervised classification, and regression. So far, our approach successfully detects anomalous resource usage when experimenting with typical trends synthesized from published real-world web server logs and cluster traces. We observe the best results with unsupervised classification, which gives an average F1-score of 0.83 for web server logs and 0.95 for the cluster traces.

2018-03-19
Chen, Z., Tondi, B., Li, X., Ni, R., Zhao, Y., Barni, M..  2017.  A Gradient-Based Pixel-Domain Attack against SVM Detection of Global Image Manipulations. 2017 IEEE Workshop on Information Forensics and Security (WIFS). :1–6.

We present a gradient-based attack against SVM-based forensic techniques relying on high-dimensional SPAM features. As opposed to prior work, the attack works directly in the pixel domain even if the relationship between pixel values and SPAM features can not be inverted. The proposed method relies on the estimation of the gradient of the SVM output with respect to pixel values, however it departs from gradient descent methodology due to the necessity of preserving the integer nature of pixels and to reduce the effect of the attack on image quality. A fast algorithm to estimate the gradient is also introduced to reduce the complexity of the attack. We tested the proposed attack against SVM detection of histogram stretching, adaptive histogram equalization and median filtering. In all cases the attack succeeded in inducing a decision error with a very limited distortion, the PSNR between the original and the attacked images ranging from 50 to 70 dBs. The attack is also effective in the case of attacks with Limited Knowledge (LK) when the SVM used by the attacker is trained on a different dataset with respect to that used by the analyst.

2018-12-10
Chen, J., Touati, C., Zhu, Q..  2017.  Heterogeneous Multi-Layer Adversarial Network Design for the IoT-Enabled Infrastructures. GLOBECOM 2017 - 2017 IEEE Global Communications Conference. :1–6.

The emerging Internet of Things (IoT) applications that leverage ubiquitous connectivity and big data are facilitating the realization of smart everything initiatives. IoT-enabled infrastructures have naturally a multi-layer system architecture with an overlaid or underlaid device network and its coexisting infrastructure network. The connectivity between different components in these two heterogeneous networks plays an important role in delivering real-time information and ensuring a high-level situational awareness. However, IoT- enabled infrastructures face cyber threats due to the wireless nature of communications. Therefore, maintaining the network connectivity in the presence of adversaries is a critical task for the infrastructure network operators. In this paper, we establish a three-player three-stage game-theoretic framework including two network operators and one attacker to capture the secure design of multi- layer infrastructure networks by allocating limited resources. We use subgame perfect Nash equilibrium (SPE) to characterize the strategies of players with sequential moves. In addition, we assess the efficiency of the equilibrium network by comparing with its team optimal solution counterparts in which two network operators can coordinate. We further design a scalable algorithm to guide the construction of the equilibrium IoT-enabled infrastructure networks. Finally, we use case studies on the emerging paradigm of Internet of Battlefield Things (IoBT) to corroborate the obtained results.

2018-01-23
Ślezak, D., Chadzyńska-Krasowska, A., Holland, J., Synak, P., Glick, R., Perkowski, M..  2017.  Scalable cyber-security analytics with a new summary-based approximate query engine. 2017 IEEE International Conference on Big Data (Big Data). :1840–1849.

A growing need for scalable solutions for both machine learning and interactive analytics exists in the area of cyber-security. Machine learning aims at segmentation and classification of log events, which leads towards optimization of the threat monitoring processes. The tools for interactive analytics are required to resolve the uncertain cases, whereby machine learning algorithms are not able to provide a convincing outcome and human expertise is necessary. In this paper we focus on a case study of a security operations platform, whereby typical layers of information processing are integrated with a new database engine dedicated to approximate analytics. The engine makes it possible for the security experts to query massive log event data sets in a standard relational style. The query outputs are received orders of magnitude faster than any of the existing database solutions running with comparable resources and, in addition, they are sufficiently accurate to make the right decisions about suspicious corner cases. The engine internals are driven by the principles of information granulation and summary-based processing. They also refer to the ideas of data quantization, approximate computing, rough sets and probability propagation. In the paper we study how the engine's parameters can influence its performance within the considered environment. In addition to the results of experiments conducted on large data sets, we also discuss some of our high level design decisions including the choice of an approximate query result accuracy measure that should reflect the specifics of the considered threat monitoring operations.

2018-03-29