Reference Model For Open Distributed Processing Research Articles

Specification of a distributed storage system

In many distributed telecommunications applications, the Quality of Service is largely determined by the performance and reliability of the distributed storage system. In this paper, we present the specification of a distributed database function which conforms to the Reference Model of Open Distributed processing (RM-ODP), the ISO/ITU-T standard. The computational model masks the distributed application from the implementation details. Fragmentation and redundancy are used to control the performance and reliability of the distributed storage system. The engineering model is based on the ODP Storage Function and Group Function.

Coloured Petri net modelling of the ODP Trader for use in resource discovery

As high speed networking becomes more widespread and increasingly accessible from home, a huge variety of new vendors and services will become available to consumers. These services will fall into three main categories: information services, shopping and entertainment. One of the major problems facing an increasingly information-rich society is how to quickly and conveniently locate information which is provided by different servers throughout a large distributed system. The Reference Model for Open Distributed Processing (RM-ODP) deals with the problem of locating services/resources in a heterogeneous open distributed system through the standardization of a Trading function which is realized by a Trader. To increase our understanding of a Trader's dynamic behaviour, a CPN model has been created. The Trader's computational viewpoint has been modelled using a hierarchy of CPNs which allow functional blocks to be modelled separately and their inter-relationships defined. A discussion of the model and techniques for its analysis are presented.

Open distributed processing: an architectural basis for information networks

The ODP Reference Model constitutes the basis of the information network architecture under development by the Telecommunications Information Networking Architecture Consortium (TINA-C). This paper briefly reviews the basic principles and concepts that underlie the ODP Reference Model, and discusses their relevance to the design and construction of information networks. In particular, it discusses binding as a fundamental element of information network structure, and presents a generic binding protocol that can support the large variety of binding instances in an information network.

Experiences of using RM-ODP to build advanced mobile applications

Significant advances have been made in recent years in tackling the problem of heterogeneity in distributed systems with ISO/ITU-T standards for a Reference Model for Open Distributed Processing (RM-ODP) now approaching international agreement. It is important, however, that such standards are responsive to new developments in computer and communications technologies. This paper reports on experiences of applying RM-ODP technology and mobile communications in supporting field workers in the electricity industry. The results of the study show that the framework provided by RM-ODP offers a strong basis for the development of mobile applications. Particular benefits are gained from the object-oriented modelling approach, the model of selective distribution transparency and the concept of QoS-managed bindings in RM-ODP. However, our experiences indicate that care must be taken in the development of RM-ODP compliant platforms particularly with respect to the communications infrastructure.

FDTs for ODP

This paper discusses the use and integration of formal techniques into the Open Distributed Processing (ODP) standardization initiative. The ODP reference model is a natural progression from OSI. Multiple viewpoints are used to specify complex ODP systems. Formal methods are playing an increasing role within ODP. We provide an overview of the ODP reference model, before discussing the ODP requirements on FDTs, and the role such techniques play. Finally, we discuss the use of formalisms in the central problem of maintaining cross viewpoint consistency.

Applying formal methods to standard development: The open distributed processing experience

Since their introduction, formal methods have been applied in various ways to different standards. This paper gives an account of these applications, focusing on one application in particular: the development of a framework for creating standards for Open Distributed Processing (ODP). Following an introduction to ODP, the paper gives an insight into the current work on formalising the architecture of the Reference Model of ODP (RM-ODP), highlighting the advantages to be gained. The different approaches currently being taken are shown, together with their associated advantages and disadvantages. The paper concludes that there is no one all-purpose approach which can be used in preference to all others, but that a combination of approaches is desirable to best fulfil the potential of formal methods in developing an architectural semantics for ODP.

The ISO Reference Model for Open Distributed Processing: an introduction

The ISO Reference Model of Open Distributed Processing (RM-ODP) consists of four parts: an Overview of the reference model, the Descriptive Model, the Prescriptive Model, and the Architectural Semantics. The four parts provide the concepts and rules of distributed processing to ensure openness between interacting distributed application components. Openness is a combination of characteristics: i.e. scalability, accessibility, heterogeneity, autonomy and distribution. The RM-ODP introduces the concept of viewpoint to describe a system from a particular set of concerns, and hence to deal with the complexity of distributed systems. While all the viewpoints are relevant to the description and design of distributed systems, the computational and engineering models are the ones that bear most directly on the design and implementation of distributed systems. From a distributed software engineering point of view, the computational and engineering viewpoints are again the most important; they reflect the software structure of the distributed application most closely. In this introductory paper, we concentrate on the computational and engineering viewpoints.

Specification of multiparty audio and video interaction based on the Reference Model of Open Distributed Processing

The Reference Model of Open Distributed Processing (RM-ODP) is an emerging ISO/ITU-T standard. It provides a framework of abstractions based on viewpoints, and it defines five viewpoint languages to model open distributed systems. This paper uses the viewpoint languages to specify multiparty audio/video exchange in distributed systems. To the designers of distributed systems, it shows how the concepts and rules of RM-ODP can be applied. The ODP “binding object” is an important concept to model continuous data flows in distributed systems. We take this concept as a basis for multiparty audio and video flow exchanges, and we provide five ODP viewpoint specifications, each emphasising a particular concern. To ensure overall correctness, special attention is paid to the mapping between the ODP viewpoint specifications.

A formal semantics for the ODP computational model

The ODP computational model is an essential part of the ODP Reference Model that provides an abstract, language-independent programming framework for open distributed systems. This paper presents a formal operational semantics for an essential subset of the ODP computational model. The semantics takes the form of a rewriting theory that provides a generic and abstract true-concurrency semantics for the ODP computational model.

CSCW requires open systems

Applications designed to support the work of groups will becoming increasingly important to future distributed systems. This paper considers the role of distributed systems within the development of cooperative systems. In particular we focus on the need to provide open Computer Supported Cooperative Work (CSCW) systems and their impact on distributed systems. The work currently being undertaken in Open Distributed Processing (ODP) is used to highlight significant trends for future open CSCW systems. It is shown that the CSCW and ODP community share mutual interests and have complementary aims and goals that are being developed from different perspectives. Within the paper we provide a brief introduction to CSCW, highlighting the requirements CSCW places on distributed systems. The development of an environment to support open CSCW systems is introduced and briefly described. Finally, the relationships between requirements and models for Open CSCW systems and the Basic Reference Model of ODP are discussed.

A system framework for open distributed processing

Emerging distributed applications increasingly require adequate tools and techniques for system- and application-level management. The integration of both aspects in an overall system framework is an important issue. This paper presents such a framework supporting advanced distributed applications in the context of the evolving Open Distributed Processing reference model. For system-level communication, an efficient subsystem providing advanced service capabilities is presented to cope with the increasing diversity of application service requirements. For application-level processing, a distributed object-based environment is offered. It implements location-independent invocation and object mobility and provides a high level of distribution transparency. The approach is augmented with tools and techniques for managing an overall application configuration.