Investigating Power Outage Effects on Reliability of Solid-State Drives

Solid-State Drives (SSDs) are recently employed in enterprise servers and high-end storage systems in order to enhance performance of storage subsystem. Although employing high speed SSDs in the storage subsystems can significantly improve system performance, it comes with significant reliability threat for write operations upon power failures. In this paper, we present a comprehensive analysis investigating the impact of workload dependent parameters on the reliability of SSDs under power failure for variety of SSDs (from top manufacturers). To this end, we first develop a platform to perform two important features required for study: a) a realistic fault injection into the SSD in the computing systems and b) data loss detection mechanism on the SSD upon power failure. In the proposed physical fault injection platform, SSDs experience a real discharge phase of Power Supply Unit (PSU) that occurs during power failure in data centers which was neglected in previous studies. The impact of workload dependent parameters such as workload Working Set Size (WSS), request size, request type, access pattern, and sequence of accesses on the failure of SSDs is carefully studied in the presence of realistic power failures. Experimental results over thousands number of fault injections show that data loss occurs even after completion of the request (up to 700ms) where the failure rate is influenced by the type, size, access pattern, and sequence of IO accesses while other parameters such as workload WSS has no impact on the failure of SSDs.Comment: Design, Automation & Test in Europe Conference & Exhibition (DATE), 2018. IEEE, 201

Web Vulnerability Study of Online Pharmacy Sites

Consumers are increasingly using online pharmacies, but these sites may not provide an adequate level of security with the consumers’ personal data. There is a gap in this research addressing the problems of security vulnerabilities in this industry. The objective is to identify the level of web application security vulnerabilities in online pharmacies and the common types of flaws, thus expanding on prior studies. Technical, managerial and legal recommendations on how to mitigate security issues are presented. The proposed four-step method first consists of choosing an online testing tool. The next steps involve choosing a list of 60 online pharmacy sites to test, and then running the software analysis to compile a list of flaws. Finally, an in-depth analysis is performed on the types of web application vulnerabilities. The majority of sites had serious vulnerabilities, with the majority of flaws being cross-site scripting or old versions of software that have not been updated. A method is proposed for the securing of web pharmacy sites, using a multi-phased approach of technical and managerial techniques together with a thorough understanding of national legal requirements for securing systems

Enhancing security behaviour by supporting the user

Although the role of users in maintaining security is regularly emphasized, this is often not matched by an accompanying level of support. Indeed, users are frequently given insufficient guidance to enable effective security choices and decisions, which can lead to perceived bad behaviour as a consequence. This paper discusses the forms of support that are possible, and seeks to investigate the effect of doing so in practice. Specifically, it presents findings from two experimental studies that investigate how variations in password meter usage and feedback can positively affect the resulting password choices. The first experiment examines the difference between passwords selected by unguided users versus those receiving guidance and alternative forms of feedback (ranging from a traditional password meter through to an emoji-based approach). The findings reveal a 30% drop in weak password choices between unguided and guided usage, with the varying meters then delivering up to 10% further improvement. The second experiment then considers variations in the form of feedback message that users may receive in addition to a meter-based rating. It is shown that by providing richer information (e.g. based upon the time required to crack a password, its relative ranking against other choices, or the probability of it being cracked), users are more motivated towards making strong choices and changing initially weak ones. While the specifics of the experimental findings were focused upon passwords, the discussion also considers the benefits that may be gained by applying the same principles of nudging and guidance to other areas of security in which users are often found to have weak behaviours

Corral

The Corral literary journal of Hardin-Simmons University includes editorials and notes regarding societies and happenings within the school as well as original creative fiction, poetry, non-fiction, drawings, and jokes

Corral

The Corral literary journal of Hardin-Simmons University includes editorials and notes regarding societies and happenings within the school as well as original creative fiction, poetry, non-fiction, drawings, and jokes

Shear bond strength of immediately repaired light-cured composite resin restorations

The goal of this study was to examine the extent to which the state of the surface of newly placed restorations made of one of two commercial formulations of composite resin (Pertac-Hybrid and Z-100) affects the interfacial bond strength when such restorations are immediately repaired with the same resin. Three groups of specimens for each material were prepared: one group in which there was an air-inhibited film on the surface of the initial layer of the restoration, another in which that film was prevented from being formed, and a third in which that surface was abraded prior to placement of the repair layer. All specimens were stored for 6 weeks in water at 23°C before being loaded to fracture in shear at a rate of 5 mm/min. The shear bond strength results were treated using the three-parameter Weibull equation and a clearly defined index of performance (I), which is a measure of both the magnitude and variability of the shear bond strength. It was found that, for two states of the surface of the initial layer, I for Pertac-Hybrid specimens is about the same as that for Z-100 specimens. For specimens made of either material, there was a demonstrable difference in I between specimens with or without an air-inhibited film on the initial layer, while abrading the surface of that layer severely degraded I. © Operative Dentistry, 1998