Configuring distributed applications at deployment time requires the introduction of high-level features such as transaction and synchronization into application's code. Component models like CORBA Component Model...
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ISBN:
(纸本)0769515886
Configuring distributed applications at deployment time requires the introduction of high-level features such as transaction and synchronization into application's code. Component models like CORBA Component Model (CCM) or Enterprise Java Beans (EJB) allow programmers to declare in deployment descriptors which services have to be plugged into components, However, these approaches do not allow a dynamic integration of new services. In this paper, we propose a reflexive approach allowing service integration into component at runtime. When a new service is added to a component, the combination with existing services is managed dynamically by the platform.
The coordination paradigm has been used extensively as a mechanism for software composition and integration. However, relatively little work has been done for the cases where the software components involved have real...
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ISBN:
(纸本)0769515886
The coordination paradigm has been used extensively as a mechanism for software composition and integration. However, relatively little work has been done for the cases where the software components involved have real-time requirements. The paper presents an extension to a state-of-the-art control- or event-driven coordination language with real-time capabilities. It then illustrates the expressiveness of the proposed extensions by means of modeling a distributed multimedia application. Finally, it discusses how these extensions can be supported by the underlying architecture.
The energy cost is one of the major concerns for the cloud providers. Virtual machine placement has been demonstrated as an effective method for energy saving. In addition to constraints caused by the physical machine...
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ISBN:
(纸本)9781509044573
The energy cost is one of the major concerns for the cloud providers. Virtual machine placement has been demonstrated as an effective method for energy saving. In addition to constraints caused by the physical machine resources such as CPU and memory (PM-constraints), the constraints caused by the network resource such as bandwidth (Net-constraints) are also crucial, since virtual machines are not isolated and require communication with each other to exchange data. However, most current research on data center power optimization only focuses on server resource. As a result, the optimization results are often inferior, because server consolidation without considering the network may cause traffic congestion and thus degraded network performance. We take the traffic demands between virtual machines into consideration and formulate the virtual machine placement problem under both PM-constraints and Net-constraints to minimize the energy cost, and propose an approach based on ant colony optimization to solve the problem. We evaluate the expected performance of our proposed algorithm through a simulation study, providing strong indications to the superiority of our proposed solution.
This paper proposes a data propagation method for improving data availability in ad hoc networks in which nodes are locally distributed. Our method makes use of a special mobile terminal which moves to transfer data i...
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ISBN:
(纸本)9781424442331
This paper proposes a data propagation method for improving data availability in ad hoc networks in which nodes are locally distributed. Our method makes use of a special mobile terminal which moves to transfer data items. Moreover the mobile terminal propagates data items effectively by deciding the moving route considering the length of the route, access requests issued by nodes, and data items held by nodes. Furthermore, we verify the effectiveness of our method by simulation experiments.
Making the network programmable simplifies network management and enables network innovations. The Recursive InterNetwork Architecture (RINA) is our solution to enable network programmability. ProtoRINA is a user-spac...
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ISBN:
(纸本)9781479962044
Making the network programmable simplifies network management and enables network innovations. The Recursive InterNetwork Architecture (RINA) is our solution to enable network programmability. ProtoRINA is a user-space prototype of RINA and provides users with a framework with common mechanisms so a user can program recursive-networking policies without implementing mechanisms from scratch. In this paper, we focus on how routing policies, which is an important aspect of network management, can be programmed using ProtoRINA, and demonstrate how ProtoRINA can be used to achieve better performance for a video streaming application by instantiating different routing policies over the GENI (Global Environment for Network Innovations) testbed, which provides a large-scale experimental facility for networking research.
A new approach is proposed for the simulation of interacting human physiological subsystems, The new simulation environment will allow users to build, analyze and solve a coupled physiological system model with distri...
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ISBN:
(纸本)078036466X
A new approach is proposed for the simulation of interacting human physiological subsystems, The new simulation environment will allow users to build, analyze and solve a coupled physiological system model with distributed subsystem models. The subsystem models as an abstract form of physiological knowledge are shared through the Internet. The simulation knowledge network includes a distributed model database, an information server, and an analysis and solution environment that will be downloaded from thp: server, To represent the coupled system, we use Differential Algebraic Equations (DAE) as the basic format. There are three common sources of DAEs in modeling of physiological systems, They are causal conflict, simulation optimization, and multistage processes. The singularly perturbed sliding manifold method is chosen for solving DAEs, Possible future improvements are discussed.
Healthcare is an information intensive industry Pervasive computing, as the third wave of computing technology and when applied to healthcare systems, could potentially revolutionize next generation medical applicatio...
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ISBN:
(纸本)9781424442331
Healthcare is an information intensive industry Pervasive computing, as the third wave of computing technology and when applied to healthcare systems, could potentially revolutionize next generation medical applications and significantly improve the quality of healthcare services. Healthcare information is very sensitive and security, privacy, and trust have been critical issues in health care and Medical Information Systems. Due to the specific features of pervasive computing, these issues become much more challenging in pervasive healthcare. In this paper, we summarize some typical healthcare services pervasive healthcare can provide, identify integration and security challenges facing pervasive healthcare systems and propose some solutions to (some) of these challenging problems.
Target localization is one of the basic functions of wireless sensor networks. In the target localization algorithms, the problem of how many sensors are needed and how they are deployed is what we are concerned about...
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ISBN:
(纸本)9781424442331
Target localization is one of the basic functions of wireless sensor networks. In the target localization algorithms, the problem of how many sensors are needed and how they are deployed is what we are concerned about in this paper. The authors of [5] present the mathematical expression of Cramer-Rao lower bound for the localization error, which is the smallest lower bound of any unbiased estimation. However it is difficult to be used to find out the relation between sensor number and Cramer-Rao lower bound directly. In this paper the relation between sensor number and Cramer-Rao lower bound is revealed by simulation. And how the topology affects the Cramer-Rao lower bound is also presented.
Consider distributed transactional memory systems where transactions residing at nodes of a communication graph operate on shared, mobile objects. A transaction requests the objects it needs, executes once those objec...
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ISBN:
(纸本)9781450389334
Consider distributed transactional memory systems where transactions residing at nodes of a communication graph operate on shared, mobile objects. A transaction requests the objects it needs, executes once those objects have been assembled, and then forwards those objects to other waiting transactions. We study the predefined order scheduling problem of committing transactions according to their priorities. This problem naturally arises in areas, such as loop parallelization and state-machine-based computing, where producing executions equivalent to a priority order is needed to satisfy certain properties. Specifically, we study predefined order scheduling considering two performance metrics fundamental to any distributed system: (i) execution time - total time to commit all the transactions and (ii) communication cost - the total distance messages travel. We design scheduling algorithms that are simultaneously efficient for both the metrics and rigorously evaluate them through several benchmarks on random and grid graphs, validating their efficiency. To the best of our knowledge, this is the first study of predefined order scheduling in distributed systems.
The success of Web services technology depends heavily on the effective discovery and sharing of services in distributed environments using various registries. These tasks should take into account both functional and ...
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ISBN:
(纸本)9781424442331
The success of Web services technology depends heavily on the effective discovery and sharing of services in distributed environments using various registries. These tasks should take into account both functional and non-functional properties (NFP) of a service. Such properties may be for example: execution time, reliability, security, cost or provider's reputation. However, currently known approaches focus mainly on the functional attributes of Web services and there is an ongoing discussion on the scope and methods that should be used to express the non-functional side of WS. This article presents an ontology of non-functional properties and shows, on the example of the WebSter registry, how it may be used within the WS discovery process in distributed environments.
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