Voici les éléments 1 - 10 sur 12
  • Publication
    Accès libre
    Simulation of communities of nodes in a wide area distributed system
    (2001)
    Yuen, Saiho
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    Unger, Herwig
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    Babin, Gilbert
    The complex structure of the Web requires decentralised, adaptive mechanisms efficiently providing access to local and global capacities. To facilitate the development of such mechanisms, it seems to be reasonable to build clusters or grids of machines with similar structures and interests. In such a manner, communities of machines can be built. In a community, every machine contributes to the overall success through a division of management work and a respective collaboration. This article presents and analyses experimental results for algorithms optimising service response times in a community. We introduce a community simulation tool, which is used to experiment with optimisation algorithms. The experimentation results are presented and analysed.
  • Publication
    Métadonnées seulement
    Message chains and disjunct paths for increasing communication performance in large networks
    (: Springer-Verlag Berlin, 2000-1-22)
    Wulff, Markus
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    ;
    Unger, Herwig
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    Babin, Gilbert
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    Plaice, John
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    Unger, Herwig
    In this paper we propose a simple powerful method to increase communication performance in large networks such as the Internet. Our approach is based on the usage multiple disjunct paths for the transmitting data from one node to another one. The method exploits the dense connectivity of the Internet by making use of the different routes engaged in communications originating from different nodes to one target nodes. We show that depending on the bandwidth offered and the amount of data to be transfered, a linear speedup can be achieved. An experimental implementation of the method within the WOS framework confirms the theoretical analysis of the method.
  • Publication
    Métadonnées seulement
    WOS: an Internet computing environment
    (: IEEE, 2000) ;
    Unger, Herwig
    ;
    Babin, Gilbert
    Given the current development of the Internet, the Web, mobile communications and services, we are clearly head- ing towards an era of widely integrated ubiquitous services sharing some kind of global operating system. This arti- cle describes the idea, the objectives and the current state of the development of the WOS-project. The Web Operat- ing System (WOS") consists of a series of versioned servers where each one can offer different services, themselves ver- sioned. Each node can act as a server or a client. A com- mon protocol, itself versioned, is used for communication among WOSNodes. Requests for services can be passed on to other servers as appropriate. The WOS is defined by the combined actions of different nodes.
  • Publication
    Accès libre
    WOS: an Internet Computing Environment
    (2000) ;
    Unger, Herwig
    ;
    Babin, Gilbert
    Given the current development of the Internet, the Web, mobile communications and services, we are clearly head- ing towards an era of widely integrated ubiquitous services sharing some kind of global operating system. This arti- cle describes the idea, the objectives and the current state of the development of the WOS-project. The Web Operat- ing System (WOS") consists of a series of versioned servers where each one can offer different services, themselves ver- sioned. Each node can act as a server or a client. A com- mon protocol, itself versioned, is used for communication among WOSNodes. Requests for services can be passed on to other servers as appropriate. The WOS is defined by the combined actions of different nodes.
  • Publication
    Accès libre
    Message Chains and Disjunct Paths for Increasing Communication Performance in Large Networks
    (2000)
    Wulff, Markus
    ;
    ;
    Unger, Herwig
    In this paper we propose a simple powerful method to increase communication performance in large networks such as the Internet. Our approach is based on the usage multiple disjunct paths for the transmitting data from one node to another one. The method exploits the dense connectivity of the Internet by making use of the different routes engaged in communications originating from different nodes to one target nodes. We show that depending on the bandwidth offered and the amount of data to be transfered, a linear speedup can be achieved. An experimentalimpl ementation of the method within the WOS framework confirms the theoretical analysis of the method.
  • Publication
    Métadonnées seulement
    Two-level communication protocol for a Web operating system (WOS (TM))
    (: IEEEComputer Soc, 1998)
    Babin, Gilbert
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    ;
    Unger, Herwig
    The World-Wide Web consists not only of informational, but also computational resources. However; these resources, especially, computational ones are underutilized. One characteristic of the Web is its ever changing structure; for instance, nodes are dynamically added and removed This makes it difficult, if not impossible, to di-aw a complete and accurate picture of available resources. We consider the Web as a versioned system: resources, services and protocols ni-e versioned. This paper presents a two-level protocol within this framework. The first protocol, the WOS Request Protocol (WOSRP), allows to select an appropriate version of a server. The second protocol, the WOS Protocol (WOSP), allows for locating and using these distributed (informational and computational) resources. We show how the latter protocol provides an efficient fault-tolerant resource search mechanism.
  • Publication
    Métadonnées seulement
  • Publication
    Accès libre
    Simulation of Search and Distribution Methods for Jobs in a WEB Operating System (WOS)
    (1998)
    Unger, Herwig
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    ;
    Babin, Gilbert
    ;
    Böhme, Thomas
    Internet or WEB computing concepts, such as the Web Operating System (WOS™), require suitable methods for finding the most effective hardware and software environment for an application execution on the network. We present an efficient search strategy and show that the resulting communication load penalty is well acceptable while preventing the network from being flooded by administrative overhead messages. Using stochastic time estimation, we demonstrate the favorable response time behavior and performance of the search algorithm.
  • Publication
    Accès libre
    Two-Level Communication Protocol for a Web Operating System (WOS)
    (1998)
    Babin, Gilbert
    ;
    ;
    Unger, Herwig
    The World-Wide Web consists not only of informational, but also computational resources. However, these resources, especially computational ones are underutilized. One characteristic of theWeb is its ever changing structure; for instance, nodes are dynamically added and removed. This makes it difficult, if not impossible, to draw a complete and accurate picture of available resources. We consider the Web as a versioned system: resources, services and protocols are versioned. This paper presents a two-level protocol within this framework. The first protocol, the WOS Request Protocol (WOSRP), allows to select an appropriate version of a server. The second protocol, the WOS Protocol (WOSP), allows for locating and using these distributed (informational and computational) resources. We show how the latter protocol provides an efficient fault-tolerant resource search mechanism.
  • Publication
    Accès libre
    Overview About the Resource Scheduling in the Web Operating System (WOS)
    (1998)
    Unger, Herwig
    ;
    A number of load sharing/balancing mechanisms were developed in order to improve the execution of a distributed application in a workstation cluster or any other kind of distribute darchitectures. In fact, it would be possible to execute applications on any machine of a world wide system. However, the notion of ‘distributed systems’ has gained in importance and attraction with the introduction of the Web. This could result in a significant performance improvement for the user. This paper describes the necessary, newly developed, principle concepts for load sharing in a world wide distributed computing environment as described in [10] to assure efficient automatic sharing of tasks.