Biblio

With the popularization of cloud computing and the deepening of its application, more and more cloud block storage systems have been put into use. The performance optimization of cloud block storage systems has become an important challenge facing today, which is manifested in the reduction of system performance caused by the unbalanced resource load of cloud block storage systems. Accurately predicting the I/O load status of the cloud block storage system can effectively avoid the load imbalance problem. However, the cloud block storage system has the characteristics of frequent random reads and writes, and a large amount of I/O requests, which makes prediction difficult. Therefore, we propose a novel I/O load prediction method for XB-IOPS feature engineering. The feature engineering is designed according to the I/O request pattern, I/O size and I/O interference, and realizes the prediction of the actual load value at a certain moment in the future and the average load value in the continuous time interval in the future. Validated on a real dataset of Alibaba Cloud block storage system, the results show that the XB-IOPS feature engineering prediction model in this paper has better performance in Alibaba Cloud block storage devices where random I/O and small I/O dominate. The prediction performance is better, and the prediction time is shorter than other prediction models.

Security is undoubtedly the most serious problem for Web applications, and SQL injection (SQLi) attacks are one of the most damaging. The detection of SQL blind injection vulnerability is very important, but unfortunately, it is not fast enough. This is because time-based SQL blind injection lacks web page feedback, so the delay function can only be set artificially to judge whether the injection is successful by observing the response time of the page. However, brute force cracking and binary search methods used in injection require more web requests, resulting in a long time to obtain database information in SQL blind injection. In this paper, a gated recurrent neural network-based SQL blind injection technology is proposed to generate the predictive characters in SQL blind injection. By using the neural language model based on deep learning and character sequence prediction, the method proposed in this paper can learn the regularity of common database information, so that it can predict the next possible character according to the currently obtained database information, and sort it according to probability. In this paper, the training model is evaluated, and experiments are carried out on the shooting range to compare the method used in this paper with sqlmap (the most advanced sqli test automation tool at present). The experimental results show that the method used in this paper is more effective and significant than sqlmap in time-based SQL blind injection. It can obtain the database information of the target site through fewer requests, and run faster.

Mobile terminals especially smartphones are changing people's work and life style. For example, mobile payments are experiencing rapid growth as consumers use mobile terminals as part of lifestyles. However, security is a big challenge for mobile application services. In order to reduce security risks, mobile terminal security assessment should be conducted before providing application services. An approach of comprehensive security assessment is proposed in this paper by defining security metrics with the corresponding scores and determining the relative weights of security metrics based on the analytical hierarchy process (AHP). Overall security assessment of Android-based mobile terminals is implemented for mobile payment services with payment fraud detection accuracy of 89%, which shows that the proposed approach of security assessment is reasonable.

The essence of network security is the asymmetric online confrontation with the partial observable cyber threats, which requires the defense ability against unexpected security incidents. The existing network intrusion detection systems are mostly static centralized structure, and usually faced with problems such as high pressure of central processing node, low fault tolerance, low damage resistance and high construction cost. In this paper, exploiting the advantage of collaborative decision-making of decentralized multiagent coordination, we design a collaborative cyber threat perception model, DI-MDPs, which is based on the decentralized coordination, and the core idea is initiative information interaction among agents. Then, we analysis the relevance and transformation conditions between the proposed model, then contribute a reinforcement learning algorithm HTI that takes advantage of the particular structure of DI-MDPs in which agent updates policies by learning both its local cognition and the additional information obtained through interaction. Finally, we compare and verify the performance of the designed algorithm under typical scenario setting.

Understanding the privacy relevant characteristics of data sets, such as reidentifiability and joinability, is crucial for data governance, yet can be difficult for large data sets. While computing the data characteristics by brute force is straightforward, the scale of systems and data collected by large organizations demands an efficient approach. We present KHyperLogLog (KHLL), an algorithm based on approximate counting techniques that can estimate the reidentifiability and joinability risks of very large databases using linear runtime and minimal memory. KHLL enables one to measure reidentifiability of data quantitatively, rather than based on expert judgement or manual reviews. Meanwhile, joinability analysis using KHLL helps ensure the separation of pseudonymous and identified data sets. We describe how organizations can use KHLL to improve protection of user privacy. The efficiency of KHLL allows one to schedule periodic analyses that detect any deviations from the expected risks over time as a regression test for privacy. We validate the performance and accuracy of KHLL through experiments using proprietary and publicly available data sets.