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An Attribute-Based Service-Request Mechanism for Heterogeneous Distributed Systems

IP.com Disclosure Number: IPCOM000128496D
Original Publication Date: 1988-Jan-01
Included in the Prior Art Database: 2005-Sep-16
Document File: 18 page(s) / 74K

Publishing Venue

Software Patent Institute

Related People

Ravishankar, C. V.: AUTHOR [+4]

Abstract

This paper presents a scheme that facilitates the integration of heterogeneous distributed systems by viewing network services abstractly in terms of their attributes. It is important in distributed systems to locate and access network services correctly, reliably, and efficiently. These problems are more acute in heterogeneous systems because the available network services tend to be more numerous and more physically distributed. Current distributed systems recognize the importance of the service location and access problems. However, they do not view services as abstract entitities. Our scheme permits clients to request a variety of service categories by enabling service specification at arbitrary levels of detail or abstraction. It also enhances reliability through a high degree of location-independence, reconfigurability, and support for service replication. In addition, clients and servers may use this scheme directly in the high-level programming language used to program them.

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THIS DOCUMENT IS AN APPROXIMATE REPRESENTATION OF THE ORIGINAL.

An Attribute-Based Service-Request Mechanism for Heterogeneous Distributed Systems

By

C.V. Ravishankar and R.N. Chang
CSE-TR-08-88

THE UNIVERSITY OF MICHIGAN

COMPUTER SCIENCE AND ENGINEERING DIVISION DEPARTMENT OF ELECTRICAL ENGINEERING AND COMPUTER SCIENCE Room 3402 EECS Building
Ann Arbor, Michigan 48109-2122
USA An Attribute-Based Service-Request Mechanism for Heterogeneous Distributed Systems1Chinya V. Ravishankar and Rong N. Chang Electrical Engineering & Computer Science Department University of Michigan-Ann Arbor
Ann Arbor, MI 48109-2122

Abstract

This paper presents a scheme that facilitates the integration of heterogeneous distributed systems by viewing network services abstractly in terms of their attributes. It is important in distributed systems to locate and access network services correctly, reliably, and efficiently. These problems are more acute in heterogeneous systems because the available network services tend to be more numerous and more physically distributed. Current distributed systems recognize the importance of the service location and access problems. However, they do not view services as abstract entitities. Our scheme permits clients to request a variety of service categories by enabling service specification at arbitrary levels of detail or abstraction. It also enhances reliability through a high degree of location-independence, reconfigurability, and support for service replication. In addition, clients and servers may use this scheme directly in the high-level programming language used to program them.

1. Introduction

The operating system kernel was the primary service provider in many older systems 2and clients used a system call interface to invoke system services. This approach suffered from serious drawbacks. Such kernels were quite complex, for example, and needed to be modified when adding new services. Even worse, the scheme did not extend to distributed environments. More modern designs therefore place servers outside the kernel. Clients request services from servers through a message-passing or a remoteprocedure-call mechanism provided by the operating system. A clear advantage of such a scheme is that it permits a high degree of physical and logical decoupling between clients and servers. For example, a server and its client may be on different network nodes running entirely different operating systems. The client and server need agree only on a common interface/protocol for interaction.

1 This work is being supported by a Faculty Development Grant from Bell Northern Research, Inc.

2 [ Mealy66 ] Mealy, G. H., B. I. Witt, and W. A. Clark, "The Functional Structure of OS/360," IBM Systems Journal 5:1 (1966), pp. 3-51.

University of Michigan EECS Department Page 1 Jan 01, 1988

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An Attribute-Based Service-Request Mechanism for Heterogeneous Distributed Systems

Despite its advantages, this clean mechanism gives rise to a...