6,971 research outputs found

    Distributed interoperable workflow support for electronic commerce.

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    Abstract. This paper describes a flexible distributed transactional workflow environment based on an extensible object-oriented framework built around class libraries, application programming interfaces, and shared services. The purpose of this environment is to support a range of EC-like business activities including the support of financial transactions and electronic contracts. This environment has as its aim to provide key infrastructure services for mediating and monitoring electronic commerce.

    Reliable scientific service compositions

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    Abstract. Distributed service oriented architectures (SOAs) are increas-ingly used by users, who are insufficiently skilled in the art of distributed system programming. A good example are computational scientists who build large-scale distributed systems using service-oriented Grid comput-ing infrastructures. Computational scientists use these infrastructure to build scientific applications, which are composed from basic Web ser-vices into larger orchestrations using workflow languages, such as the Business Process Execution Language. For these users reliability of the infrastructure is of significant importance and that has to be provided in the presence of hardware or operational failures. The primitives avail-able to achieve such reliability currently leave much to be desired by users who do not necessarily have a strong education in distributed sys-tem construction. We characterise scientific service compositions and the environment they operate in by introducing the notion of global scien-tific BPEL workflows. We outline the threats to the reliability of such workflows and discuss the limited support that available specifications and mechanisms provide to achieve reliability. Furthermore, we propose a line of research to address the identified issues by investigating auto-nomic mechanisms that assist computational scientists in building, exe-cuting and maintaining reliable workflows.

    Robust collaborative services interactions under system crashes and network failures

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    Electronic collaboration has grown significantly in the last decade, with applications in many different areas such as shopping, trading, and logistics. Often electronic collaboration is based on automated business processes managed by different companies and connected through the Internet. Such a business process is normally deployed on a process engine, which is a piece of software that is able to execute the business process with the help of infrastructure services (operating system, database, network service, etc.). With the possibility of system crashes and network failures, the design of robust interactions for collaborative processes is a challenge. System crashes and network failures are common events, which may happen in various information systems, e.g., servers, desktops, mobile devices. Business processes use messages to synchronize their state. If a process changes its state, it sends a message to its peer processes in the collaboration to inform them about this change. System crashes and network failures may result in loss of messages. In this case, the state change is performed by some but not all processes, resulting in global state/behavior inconsistencies and possibly deadlocks. In general, a state inconsistency is not automatically detected and recovered by the process engine. Recovery in this case often has to be performed manually after checking execution traces, which is potentially slow, error prone and expensive. Existing solutions either shift the burden to business process developers or require additional infrastructure services support. For example, fault handling approaches require that the developers are aware of possible failures and their recovery strategies. Transaction approaches require a coordinator and coordination protocols deployed in the infrastructure layer. Our idea to solve this problem is to replace each original process by a robust counterpart, which is obtained from the original process through an automatic transformation, before deployment on the process engine. The robust process is deployed with the same infrastructure services and automatically recovers from message loss and state inconsistencies caused by system crashes and network failures. In other words, the robust processes are transparent to developers while leaving the infrastructure unmodified. We assume a synchronous interaction scenario for collaborative processes. With this scenario, an initiator sends a request message to a responder, and waits for a response message, while a responder receives the request message, applies some state change and sends the response messages. With our proposed transformation we obtain robust processes, where each process in the responder role caches the response message if its state has changed by the previously received request message. The possible state inconsistencies are recognized by using timers and information provided by the infrastructure, and resolved by using cached state and by retrying failed interactions. We also considered more complex interaction scenarios with multiple initiator and responder instances (1-n, n-1 and n-n client-server configurations). We have provided a formal proof of the correctness of our transformation solution. We have also done a performance analysis and determined the overhead of the generated (robust) processes compared to the original processes. Since this overhead is low compared to the performance differences that exist as a consequence of using different process engines, we argue that the generated robust processes have applicability in real life business environments. By doing this work, we have learnt the possible failure situations that affect the global state/behavior of collaborative business processes. Furthermore, we have defined transformations for deriving robust processes that are capable of surviving the identified failures

    BUILDING RELIABLE AND ROBUST SERVICE-BASED SYSTEMS FOR AUTOMATED BUSINESS PROCESSES

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    An exciting trend in enterprise computing lies in the integration of applications across an organisation and even between organisations. This allows the provision of services by automated business processes that coordinate business activity among several collaborating organisations. The best successes in this type of integrated distributed system come through use of Web Services and Service-based Architecture, which allow interoperation between applications through open standards based on XML and SOAP. But still, there are unresolved issues when developers seek to build a reliable and robust system. An important goal for the designers of a loosely coupled distributed system is to maintain consistency for each long running business process in the presence of failures and concurrent activities. Our approach to assist the developers in this domain is to guide the developers with the key principles they must consider, and to provide programming models and protocols, which make it easier to detect and avoid consistency faults in service-based system. We start by defining a realistic e-procurement scenario to illustrate the common problems faced by the developers which prevent them from building a reliable and robust system. These problems make it hard to maintain the consistency of the data and state during the execution of a business process in the occurrence of failures and interference from concurrent activities. Through the analysis of the common problems, we identify key principles the developers must consider to avoid producing the common problems. Then based on the key principles, we provide a framework called GAT in the orchestration infrastructure. GAT allows developers to express all the necessary processing to handle deviations including those due to failures and concurrent activities. We discuss the GAT framework in detail with its structure and key features. Using an example taken from part of the e-procurement case study, we illustrate how developers can use the framework to design their business requirements. We also discuss how key features of the new framework help the developers to avoid producing consistency faults. We illustrate how systems based on our framework can be built using today’s proven technology. Finally, we provide a unified isolation mechanism called Promises that is not only applicable to our GAT framework, but also to any applications that run in the service-based world. We discuss the concept, how it works, and how it defines a protocol. We also provide a list of potential implementation techniques. Using some of the implementation techniques we mention, we provide a proof-of-concept prototype system

    Fighting Poverty, Profitably: Transforming the Economics of Payments to Build Sustainable, Inclusive Financial Systems

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    The Gates Foundation's Financial Services for the Poor program (FSP) believes that effective financial services are paramount in the fight against poverty. Nonetheless, today more than 2 billion people live outside the formal financial sector. Increasing their access to high quality, affordable financial services will accelerate the well-being of households, communities, and economies in the developing world. One of the most promising ways to deliver these financial services to the poor -- profitably and at scale -- is by using digital payment platforms.These are the conclusions we have reached as the result of extensive research in pursuit of one of the Foundation's primary missions: to give the world's poorest people the chance to lift themselves out of hunger and extreme poverty.FSP conducted this research because we believe that there is a gap in the fact base and understanding of how payment systems can extend digital services to low income consumers in developing markets. This is a complex topic, with fragmented information and a high degree of country-by-country variability. A complete view across the entire payment system has been missing, limiting how system providers, policy makers, and regulators (groups we refer to collectively as financial inclusion stakeholders) evaluate decisions and take actions. With a holistic view of the payment system, we believe that interventions can have higher impact, and stakeholders can better understand and address the ripple effects that changes to one part of the system can have. In this report, we focus on the economics of payment systems to understand how they can be transformed to serve poor people in a way that is profitable and sustainable in aggregate

    Managing at the Speed of Light: Improving Mission-Support Performance

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    The House and Senate Energy and Water Development Appropriations Subcommittees requested this study to help DOE's three major mission-support organizations improve their operations to better meet the current and future needs of the department. The passage of the Recovery Act only increased the importance of having DOE's mission-support offices working in the most effective, efficient, and timely manner as possible. While following rules and regulations is essential, the foremost task of the mission-support offices is to support the department's mission, i.e., the programs that DOE is implementing, whether in Washington D.C. or in the field. As a result, the Panel offered specific recommendations to strengthen the mission-focus and improve the management of each of the following support functions based on five "management mandates":- Strategic Vision- Leadership- Mission and Customer Service Orientation- Tactical Implementation- Agility/AdaptabilityKey FindingsThe Panel made several recommendations in each of the functional areas examined and some overarching recommendations for the corporate management of the mission-support offices that they believed would result in significant improvements to DOE's mission-support operations. The Panel believed that adopting these recommendations will not only make DOE a better functioning organization, but that most of them are essential if DOE is to put its very large allocation of Recovery Act funding to its intended uses as quickly as possible
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