A Framework for QoS-aware Execution of Workflows over the Cloud

The Cloud Computing paradigm is providing system architects with a new powerful tool for building scalable applications. Clouds allow allocation of resources on a "pay-as-you-go" model, so that additional resources can be requested during peak loads and released after that. However, this flexibility asks for appropriate dynamic reconfiguration strategies. In this paper we describe SAVER (qoS-Aware workflows oVER the Cloud), a QoS-aware algorithm for executing workflows involving Web Services hosted in a Cloud environment. SAVER allows execution of arbitrary workflows subject to response time constraints. SAVER uses a passive monitor to identify workload fluctuations based on the observed system response time. The information collected by the monitor is used by a planner component to identify the minimum number of instances of each Web Service which should be allocated in order to satisfy the response time constraint. SAVER uses a simple Queueing Network (QN) model to identify the optimal resource allocation. Specifically, the QN model is used to identify bottlenecks, and predict the system performance as Cloud resources are allocated or released. The parameters used to evaluate the model are those collected by the monitor, which means that SAVER does not require any particular knowledge of the Web Services and workflows being executed. Our approach has been validated through numerical simulations, whose results are reported in this paper

WS-ARC service configuration manual

The central component of AR

Assessing the Evidence About Work Support Benefits and Low-Income Families

Reviews research on factors affecting participation in work supports such as Medicaid, Children's Health Insurance, Supplemental Nutrition Assistance, and childcare subsidy programs; the programs' payoff, and state benefits of modernized delivery systems

Zambia's infrastructure : a continental perspective

Infrastructure improvements contributed 0.6 percentage points to Zambia's annual per capital GDP growth over the past decade, mostly because of exponential growth in information and communication services. The power sector, by contrast, pulled the growth rate down by more than 0.1 percentage points. Improving Zambia's infrastructure endowment could boost growth by up to 2 percentage points per year. Zambia's relatively high generation capacity and power consumption are accompanied by fewer power outages than elsewhere in the region. But Zambia's power sector emphasizes the mining industry, while household electrification is about half that in other resource-rich countries. Zambia's power tariffs, among the lowest in Africa, are less than half the level needed to accelerate electrification and keep pace with mining sector demands. In power as in just about every other aspect of infrastructure, rural Zambians lag well behind their African peers. In a country where 70 percent of the population depends on agriculture for its livelihood, this represents a huge drag on the economy. Zambia would need to spend an average of $1.6 billion a year over the decade 2006-15 to develop the infrastructure found in the rest of the developing world. This is equivalent to 20 percent of Zambia's GDP and about double the country's rate of investment in recent years. Closing the country's annual infrastructure funding gap of$500 million requires raising more funds, looking for more cost-effective ways to meet infrastructure targets, and eliminating the inefficiencies that cause the loss of $300 million annually.Transport Economics Policy&Planning,Infrastructure Economics,Energy Production and Transportation,Town Water Supply and Sanitation,Banks&Banking Reform

Ethiopia's infrastructure: a continental perspective

Infrastructure contributed 0.6 percentage points to Ethiopia's annual per capita GDP growth over the last decade. Raising the country's infrastructure endowment to that of the region's middle-income countries could add an additional 3 percentage points to infrastructure's contribution to growth. Ethiopia's infrastructure successes include developing Ethiopia Airlines, a leading regional carrier; upgrading its network of trunk roads; and rapidly expanding access to water and sanitation.The country's greatest infrastructure challenge lies in the power sector, where a further 8,700 megawatts of generating plant are needed over the next decade, implying a doubling of current capacity. The transport sector faces the challenges of low levels of rural accessibility and inadequate road maintenance. Ethiopia’s ICT sector currently suffers from a poor institutional and regulatory framework. Addressing Ethiopia's infrastructure deficit will require a sustained annual expenditure of $5.1 billion over the next decade. The power sector alone requires$3.3 billion annually, with $1 billion needed to facilitate regional power trading. That level of spending represents 40 percent of the country's GDP and a tripling of the$1.3 billion spent annually in the mid-2000s. As of 2006, there was an annual funding gap of $3.5 billion. Improving road maintenance, removing inefficiencies in power (notably underpricing), and privatizing ICT services could shrink the gap. But Ethiopia needs a significant increase in its already proportionally high infrastructure funding and careful handling of public and private investments if it is to reach its infrastructure targets within a reasonable time.Transport Economics Policy&Planning,Infrastructure Economics,Public Sector Economics,Banks&Banking Reform,Town Water Supply and Sanitation

Securely Consume Web Services Using PHP

The PHP: Hypertext Preprocessor language (PHP) has evolved to a sophisticated mainstream programming language for rapid development of significant Web applications at major sites including Facebook.com, Wikipedia.org and Yahoo.com. Leading software vendors such as Oracle and IBM are rushing in providing tools that bridge their products to PHP. However, we have observed a gap in facilitating PHP to utilize Web services efficiently. This thesis reports our efforts in design and implementation of PHP applications that consume Web services. In doing so, I have proposed a framework facilitating PHP programs to utilize Web services with high performance capability. In addition, a number of Web service standards including WS-Addressing and those in WS-Security are integrated into my PHP implementation. Examples of using various Amazon Web Services are provided with details

Securely Consume Web Services Using PHP

The PHP: Hypertext Preprocessor language (PHP) has evolved to a sophisticated mainstream programming language for rapid development of significant Web applications at major sites including Facebook.com, Wikipedia.org and Yahoo.com. Leading software vendors such as Oracle and IBM are rushing in providing tools that bridge their products to PHP. However, we have observed a gap in facilitating PHP to utilize Web services efficiently. This thesis reports our efforts in design and implementation of PHP applications that consume Web services. In doing so, I have proposed a framework facilitating PHP programs to utilize Web services with high performance capability. In addition, a number of Web service standards including WS-Addressing and those in WS-Security are integrated into my PHP implementation. Examples of using various Amazon Web Services are provided with details

A Review on Framework and Quality of Service Based Web Services Discovery

Selection of Web services (WSs) is one of the most important steps in the application of different types of WSs such as WS composition systems and the Universal Description, Discovery, and Integration (UDDI) registries. The more available these WSs on the Internet are, the wider the number of these services whose functions match the various service requests is. Selecting WSs with higher quality largely depends on the quality of service (QoS) since it plays a significant role in selecting such services. In achieving this selection of the best WSs, the potential WSs are ranked according to the user’s necessities on service quality. In many cases, the value of QoS ontology is realized by its support for nonfunctional features of WSs. This ontology is also capable of providing solutions to the interoperability of QoS description. Moreover, based on the QoS ontology, it becomes more possible to develop a framework of semantic WS discovery. The framework enhances the automatic discovery of WSs and can improve the users’ efficiency in finding the best web services. Thus, Web Services are software functionalities publish and accessible through the Internet. Different protocols and web mechanism have been defined to access these Services