There is a need for information exchange and communication between management applications that are distributed over a large system. In this situation, a fundamental problem is how the management systems should cooper...
This article argues that the mobile agent approach is well suited for sporadic communication in open distributedsystems, especially for rather ''loose '' cooperations across focal and organization of ...
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This article argues that the mobile agent approach is well suited for sporadic communication in open distributedsystems, especially for rather ''loose '' cooperations across focal and organization of boundaries. In an increasing number of cases, management of distributed business procedures reaches beyond such boundaries. This means, for most existing workflow management systems that cooperating partners are required to give up their focal autonomy. However for cases in which business partners intend to cooperate but still need To preserve their local autonomy, process participation on the basis of mobile agents represents an appropriate mechanism. This article shows how such process integration can be achieved. it also demonstrates how the Common Open Service Market (COSM) system software can be extended in order to use petri-net based process definitions that realize mobile agents in an integrated distributed system platform.
Object databases have been recognized as providing rich data modeling capabilities for the next generation applications, especially CAD/CAM, software engineering, and multimedia, The core object model consisting of ob...
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Object databases have been recognized as providing rich data modeling capabilities for the next generation applications, especially CAD/CAM, software engineering, and multimedia, The core object model consisting of objects, messages and inheritance, however, is not adequate to tackle all the requirements of these applications, Since collaborative activity is one of the key features of next-generation applications, it is essential that the basic object model be extended to support collaborative activity, We propose an object model for collaborative designing based on objects and constraint meta-objects. Each design object has an associated constraint space consisting of one or more constraint meta objects. The object/constraint meta-object separation achieves a clear distinction between design object and its associated design environment and provides a framework for supporting collaboration among members of a design team, Collaboration is modeled as dependencies among multiple constraint spaces on different nodes, and collaborative activity as design transactions satisfying local constraints and propagating constraints among interrelated constraint spaces, We propose language extensions to C++ for capturing the object/constraint meta-object paradigm. The extensions are implemented using filters, a special mechanism for capturing messages sent to an object, Our model has been applied to the case of a mechanical CAD problem.
The provision of services such as credit card facilities using Intelligent Networks (IN) depends upon the ability to process real-time data. If their data is deliberately delayed during transit, these services may not...
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The provision of services such as credit card facilities using Intelligent Networks (IN) depends upon the ability to process real-time data. If their data is deliberately delayed during transit, these services may not be able to function accurately. This paper examines INs and highlights their vulnerability to network delay attacks. In particular, the nature of rear-time communications and the main approach that has been developed to determine whether received data is being sent in real-time or not is discussed. The deficiencies in this approach in terms of its ability to counteract the different forms of a network delay attack are highlighted and an alternative method which addresses these drawbacks is presented. Finally, the results achieved following the implementation and subsequent testing of the alternative approach are discussed. (C) 1997 Elsevier science B.V.
Applications that cross the boundaries of different computing machines, operating systems, and programming languages are increasingly the norm. As a result, the need for what might be called bridging technologies to d...
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Applications that cross the boundaries of different computing machines, operating systems, and programming languages are increasingly the norm. As a result, the need for what might be called bridging technologies to develop software that works across heterogeneous environments has become more compelling. The Common Object Request Broker Architecture is one such technology that is both robust and commercially available. CORBA essentially describes how client applications can invoke operations on server objects using the services of an intermediary known as an Object Request Broker, or ORB. This article introduces CORBA by describing its key components. It then reviews the boundaries it helps to bridge. It concludes by comparing CORBA with a number of other bridging technologies available today.
Several international standards for asynchronous data compression are available today. In 1993 the International Telecommunication Union (ITU) started to research possible ways to compress synchronous data. Special at...
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Several international standards for asynchronous data compression are available today. In 1993 the International Telecommunication Union (ITU) started to research possible ways to compress synchronous data. Special attention was given to compatibility with previous asynchronous standards, namely V.42bis. In September 1993 a proposal for modification of the V.42bis standard to make ii applicable to synchronous data was published. In this paper a prototype of a synchronous data link layer protocol based on the ITU proposals is described. The protocol chosen is HDLC based. The V.42bis compression standard is adapted to serve the needs of a synchronous protocol. A functional model is designed followed by a performance analysis of the protocol. The analysis shows a decrease of the compression ratio due to the adaption of the compression algorithm. (C) 1997 Elsevier science B.V.
This paper presents a mobile agent approach that aims at satisfying the following requirements of open Internet-based electronic service markets: the mobile agent system should be usable by any Internet user without a...
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ISBN:
(纸本)3540628037
This paper presents a mobile agent approach that aims at satisfying the following requirements of open Internet-based electronic service markets: the mobile agent system should be usable by any Internet user without a need for specifically configurated non-standard software tools. It should reduce costs in mobile computing environments and therefore enhance overall efficiency. It should suit well to an electronic service market where local services are commercially offered and business transactions predominate the interaction between customers and suppliers. As a part of the project OSM (Open Service Model), mobile agents are built on top of two well-established technologies: CORBA and Java. The first is used as a conceptual framework for interoperability, the latter as the programming environment. Since Java does not provide the necessary persistency of execution state, the concept of OSM service profiles is used to embed Java classes and to transfer a coarse-grained execution context in a secure and efficient manner.
Advances in directory services, caching and replication, and multicasting technologies promise to improve the speed and robustness of the Web's infrastructure. This article examines the technical issues of two imp...
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Advances in directory services, caching and replication, and multicasting technologies promise to improve the speed and robustness of the Web's infrastructure. This article examines the technical issues of two important approaches - Caching and replication.
In mobile collaborative applications, collaborating agents can move across heterogeneous networks. The collaborating agents also keep changing their roles depending on the work to be performed at that time. I n such s...
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