Publish/subscribe systems have gained increasing interest in the past few years. There are many commercial products available today that rely on them directly. However, up to now there has been no discussion about pri...
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ISBN:
(纸本)1581139306
Publish/subscribe systems have gained increasing interest in the past few years. There are many commercial products available today that rely on them directly. However, up to now there has been no discussion about pricing in such systems. We present a new strategyproof distributed algorithm that calculates the maximum subtree of the broker network and the costs arising for the clients. These payments sum up to the amount defined by the marginal cost mechanism and maximize the social surplus (i.e. the sum of the utilities minus the costs). It is taken into account that there may be multiple publishers serving one filter. An extended self-stabilized version copes with systems whose structure underlies a permanent change when publishers (dis-)appear and client utility changes. An adjustment is presented that considers different rates for subscriptions and therefore weakens the previous all-or-nothing scenario. Copyright 2004 ACM.
Web services are the key technology for implementing distributed enterprise level applications such as B2B and grid computing. An important goal is to provide dependable quality guarantees for client-server interactio...
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Web services are the key technology for implementing distributed enterprise level applications such as B2B and grid computing. An important goal is to provide dependable quality guarantees for client-server interactions. Therefore, service level management (SLM) is gaining more and more significance for clients and providers of Web services. The first step to control service level agreements is a proper instrumentation of the application code in order to monitor the service performance. However, manual instrumentation of Web services is very costly and error-prone and thus not very efficient. Our goal was to develop a systematic and automated, tool-supported approach for Web services instrumentation. We present a dual approach for efficiently instrumenting Web services. It consists of instrumenting the frontend Web services platform as well as the backend services. Although the instrumentation of the Web services platform necessarily is platform-specific, we have found a general, reusable approach. On the backend-side aspect-oriented programming techniques are successfully applied to instrument backend services. We present experimental studies of performance instrumentation using the application response measurement (ARM) API and evaluate the efficiency of the monitoring enhancements. Our results point the way to systematically gain better insights into the behaviour of Web services and thus how to build more dependable Web-based applications.
Service level management (SLM) has gained more and more importance in the past few years. One of the biggest challenges is the integration of emerging new technologies such as Web services. A large number of different...
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Service level management (SLM) has gained more and more importance in the past few years. One of the biggest challenges is the integration of emerging new technologies such as Web services. A large number of different SLM approaches has been proposed which complicates an efficient SLM. This paper describes an SLM approach that is based on the model driven architecture (MDA). The first step is to specify abstract reusable SLA patterns which are bound later to a concrete management platform and are finally physically deployed into the managed environment. This approach benefits from the advantages of the MDA and provides a mechanism for transforming SLA patterns for different SLA management platforms. Our approach has been prototypically implemented for the Web services level agreement (WSLA) environment.
The way we work is changing fundamentally. Broadly available mobile networks give us the technical opportunity to be more flexible in time and space. The better understanding of learning organizations leads to a reorg...
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This paper summarizes the key requirements for the system, presents an object‐oriented model of the heterogeneous networks, and gives a brief description of the main functional parts of the system. The model discusse...
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