Power Management Techniques for Data Centers: A Survey

With growing use of internet and exponential growth in amount of data to be stored and processed (known as 'big data'), the size of data centers has greatly increased. This, however, has resulted in significant increase in the power consumption of the data centers. For this reason, managing power consumption of data centers has become essential. In this paper, we highlight the need of achieving energy efficiency in data centers and survey several recent architectural techniques designed for power management of data centers. We also present a classification of these techniques based on their characteristics. This paper aims to provide insights into the techniques for improving energy efficiency of data centers and encourage the designers to invent novel solutions for managing the large power dissipation of data centers.Comment: Keywords: Data Centers, Power Management, Low-power Design, Energy Efficiency, Green Computing, DVFS, Server Consolidatio

KeyForge: Mitigating Email Breaches with Forward-Forgeable Signatures

Email breaches are commonplace, and they expose a wealth of personal, business, and political data that may have devastating consequences. The current email system allows any attacker who gains access to your email to prove the authenticity of the stolen messages to third parties -- a property arising from a necessary anti-spam / anti-spoofing protocol called DKIM. This exacerbates the problem of email breaches by greatly increasing the potential for attackers to damage the users' reputation, blackmail them, or sell the stolen information to third parties. In this paper, we introduce "non-attributable email", which guarantees that a wide class of adversaries are unable to convince any third party of the authenticity of stolen emails. We formally define non-attributability, and present two practical system proposals -- KeyForge and TimeForge -- that provably achieve non-attributability while maintaining the important protection against spam and spoofing that is currently provided by DKIM. Moreover, we implement KeyForge and demonstrate that that scheme is practical, achieving competitive verification and signing speed while also requiring 42% less bandwidth per email than RSA2048

Municipal Implementation Tool #19 - Freight Transportation

Freight transportation affects every aspect of the Philadelphia metropolitan area and its 353 municipalities. Everyday essentials, such as food, clothes, and energy, are made available by a massive global supply chain that transports goods to market. Freight is a necessary aspect of any vibrant community.Freight facilities provide a viable source of jobs for local residents as well as high tax revenues for local government. Local governments need these revenues to keep property taxes from rising and to pay for services such as education, trash collection, and police and fire.Freight jobs typically provide high, family-supporting wages. Recently, the historic U.S. Steel Fairless Works facility in Bucks County, Pennsylvania has been subdivided and redeveloped into various manufacturing sites. Since 2004, the redevelopment has created 3,000 jobs in wind and solar power, biofuels manufacturing, and other areas supporting these sectors.This brochure has been prepared by the Delaware Valley Regional Planning Commission (DVRPC) to help local governments and the general public better understand trends and adopt strategies to better manage freight transportation in their communities. As part of a series of municipal implementation tools prepared by DVRPC, this report tackles some local freight issues, such as:freight-related land use;truck parking and routes;air quality; andsafety

A Taxonomy of Data Grids for Distributed Data Sharing, Management and Processing

Data Grids have been adopted as the platform for scientific communities that need to share, access, transport, process and manage large data collections distributed worldwide. They combine high-end computing technologies with high-performance networking and wide-area storage management techniques. In this paper, we discuss the key concepts behind Data Grids and compare them with other data sharing and distribution paradigms such as content delivery networks, peer-to-peer networks and distributed databases. We then provide comprehensive taxonomies that cover various aspects of architecture, data transportation, data replication and resource allocation and scheduling. Finally, we map the proposed taxonomy to various Data Grid systems not only to validate the taxonomy but also to identify areas for future exploration. Through this taxonomy, we aim to categorise existing systems to better understand their goals and their methodology. This would help evaluate their applicability for solving similar problems. This taxonomy also provides a "gap analysis" of this area through which researchers can potentially identify new issues for investigation. Finally, we hope that the proposed taxonomy and mapping also helps to provide an easy way for new practitioners to understand this complex area of research.Comment: 46 pages, 16 figures, Technical Repor

A study of System Interface Sets (SIS) for the host, target and integration environments of the Space Station Program (SSP)

System interface sets (SIS) for large, complex, non-stop, distributed systems are examined. The SIS of the Space Station Program (SSP) was selected as the focus of this study because an appropriate virtual interface specification of the SIS is believed to have the most potential to free the project from four life cycle tyrannies which are rooted in a dependance on either a proprietary or particular instance of: operating systems, data management systems, communications systems, and instruction set architectures. The static perspective of the common Ada programming support environment interface set (CAIS) and the portable common execution environment (PCEE) activities are discussed. Also, the dynamic perspective of the PCEE is addressed

Dagstuhl News January - December 1999

"Dagstuhl News" is a publication edited especially for the members of the Foundation "Informatikzentrum Schloss Dagstuhl" to thank them for their support. The News give a summary of the scientific work being done in Dagstuhl. Each Dagstuhl Seminar is presented by a small abstract describing the contents and scientific highlights of the seminar as well as the perspectives or challenges of the research topic

SwitchWare: Accelerating Network Evolution (White Paper)

We propose the development of a set of software technologies ( SwitchWare ) which will enable rapid development and deployment of new network services. The key insight is that by making the basic network service selectable on a per user (or even per packet) basis, the need for formal standardization is eliminated. Additionally, by making the basic network service programmable, the deployment times, today constrained by capital funding limitations, are tremendously reduced (to the order of software distribution times). Finally, by constructing an advanced, robust programming environment, even the service development time can be reduced. A SwitchWare switch consists of input and output ports controlled by a software-programmable element; programs are contained in sequences of messages sent to the SwitchWare switch\u27s input ports, which interpret the messages as programs. We call these Switchlets . This accelerates the pace of network evolution, as evolving user needs can be immediately reflected in the network infrastructure. Immediate reconfigurability enhances the adaptability of the network infrastructure in the face of unexpected situations. We call a network built from SwitchWare switches an active network

The Prescription Opioid Epidemic: an Evidence-Based Approach

A group of experts, led by researchers at the Johns Hopkins Bloomberg School of Public Health, issued this report aimed at stemming the prescription opioid epidemic, a crisis that kills an average of 44 people a day in the U.S. The report calls for changes to the way medical students and physicians are trained, prescriptions are dispensed and monitored, first responders are equipped to treat overdoses, and those with addiction are identified and treated. The report grew out of discussions that began last year at a town hall co-hosted by the Bloomberg School and the Clinton Health Matters Initiative, an initiative of the Clinton Foundation. The recommendations were developed by professionals from medicine, pharmacy, injury prevention and law. Patient representatives, insurers and drug manufacturers also participated in developing the recommendations. The report breaks its recommendations into seven categories:Prescribing GuidelinesPrescription Drug Monitoring Programs (PDMPs)Pharmacy Benefit Managers (PBMs) and PharmaciesEngineering Strategies (i.e., packaging)Overdose Education and Naloxone Distribution ProgramsAddiction TreatmentCommunity-Based Prevention Strategie