Skip to main content
main-content

Über dieses Buch

1.1 Scope This paper deals with the following subjects: 1. Introduction 2. Feasibility study definition in IT 3. Forming a feasibility study team 4. The feasibility study work 5. The feasibility study report 6. Discussion 1.2 Information Technology (IT) Information was defined as anything sensed by at least one of the human senses and that may change the level of his knowledge. The information may be true or false, sent by premeditation or generated by coincidence, needed by the interceptor or intended to create new needs. The creation of the information may be very costly or free of charge. The information may be an essential need or just a luxury. Each information may be a one shot nature, eg., announcing a marriage, or a constant update need one, eg., news. Information technology as defined herein means all the types of systems needed to deal wi.th the information, transfer it to any place, store it, adapt it, etc. Information technology is usually bused on Telecommunications. Telecommunications means a large variety of possibilities. Usually, the IT's are based on the creation, updating, processing and transmission of information. The information itself is usually alphanumeric and graphic. Gradually, there is a tendency to step over to what is seen as more natural information, audio and visual.

Inhaltsverzeichnis

Frontmatter

Information Technology

Frontmatter

Information Technology — The Requirements

Abstract
Information technology is difficult to define, at least, it is difficult to limit the definition but it certainly includes office automation, messaging, data processing, industrial and process control, database systems, learning systems and computing.
Keith Bartlett

Feasibility Studies on New Information Technologies

Abstract
The eighties are foreseen as the dawn of the information age. Information is defined as anything that may change the level of knowledge (entropy) of human beings. The information acts on every sense of the human. In this paper, we shall limit the discussion only to the senses of seeing and hearing. Information is still supplied to people in most cases in conventional ways. Therefore, as more and more people deal with creating information, the amount of information received by anybody has become tremendous. People can’t withstand the information received unless they filter out a large part of it.
New information techologies (LT) appear one after the other. People have various possibilities to solve, the same problem. Many of the possible new information technologies are technologies looking for problems and markets.
Many countries are in the same quandry.
Which information technology (IT) to select? How and where to introduce it? Th i.a is a need to make feasibility studies before the selection process. Sometimes pilot projects are indicated; sometimes they may be skipped.
By forming a proper feasibility study team and defining well its framework, significant future outlays can be avoided.
This paper suggests possible ways to deal with feasibility studies with the purpose of reaching the proper decisions once such a process is finalized.
David Biran

Introduction to the Workshop Session on “The Merging of Defence and Civilian Interests in Computer Communications”

Abstract
All of us here have a deep interest in the future of information technology. Many of us are actively working towards a future in which information technology will be a fundamental component of our society’s infrastructure. I am not sure whether we are already in the midst of a technological revolution; but the development of electronics, computing, and telecommunications is indeed bringing about changes in our industrial and social life, and it is particularly affecting the ways that our companies, corporations and government departments conduct their business. If we scientists, engineers and technologists are successful in developing and promoting the ideas that we are discussing at this Advanced Study Institute, there may indeed be a revolution, and we must bear some responsibility for the acceptability of the outcome.
R. N. MacKenzie

Standardisation

Frontmatter

Open Systems Interconnection

Abstract
Open Systems Interconnection (OSI) refers to communications between computer systems which can freely exchange information by virtue of their mutual adherence to a set of standards. The standards in question are based on an architechtural model of communications systems, known as the Reference Model for Open Systems Interconnection (OSI). This model is the starting point for looking at OSI, and provides a much needed framework for the orderly development of standards for information interchange.
W. A. McCrum

Issues in Multimedia Computer-Based Message System Design and Standardization

Abstract
Computer-based message systems are increasingly being used for formal and informal communication, supporting the exchange of textual messages. However such nontext media as voice and graphics are very important for human communication. As a result, there is a growing need for the support of media other than text in such systems.
This paper addresses various technical issues that will be decisive for the future implementation and standardization of multimedia message systems. Such issues range from new mechanisms for the distribution of multimedia mail to the design of editing tools for nontext media.
Jose J. Garcia Luna Aceves, Franklin F. Kuo

Practical Benefits from Standardisation

Summary
This paper highlights the advantages and disadvantages of adopting standards and briefly describes the present standards scene. The redevelopment of the South West Universities Computer Network is then used as a case study to show the need for a coherent development strategy and well planned transition route when adopting standards in a live user network.
J. R. Brookes, J. S. Thomas

Information Services

Frontmatter

The SERC Network — Its History and Development

Summary
The Rutherford Laboratory of the UK Science and Engineering Research Council (SERC) has provided computing facilities to university located scientists since the early 1960s. The facilities now offered are very varied and are provided on a large number of dissimilar computers located at many sites. To allow easy access to and from these facilities a sophisticated network now exists to interconnect them. This network has developed steadily since the early 1970s and is now a very substantial network with over 160 hosts.
It is, in fact, about half the size of the UK public network PSS. This paper describes the development of this network and discusses some of the difficulties encountered and the decision taken from time to time.
P. Bryant

SITA Advanced Telecommunications Services

Abstract
As is now widely known, the world of telecommunications is undergoing a profound mutation and accelerated development with the emergence and introduction of new telecommunications services in all aspects of human and systems communications. The progressive introduction of services, such as Videotex, Teletex, Telefax, Teleconferencing and Videoconferencing in the business, social and individual environment, and the worldwide availability of low cost data communication made possible by the international deployment of data networks and satellite systems, are likely to induce lasting changes in many aspects of human activities, and to have an impact as important in the future as the introduction of computers thirty years ago.
Georges Giraudbit

Names, Addresses, and Directory Services for Computer Mail

Abstract
In an environment of several computer-based message systems (CBMS) interconnecting companies both within and beyond national borders, users would find it quite inconvenient to have to refer to one another by means of system addresses. Furthermore, users operating in a distributed environment may have multiple addresses and change their locations fairly frequently. To support better management of system resources, therefore, a mapping service from names to addresses would be a desirable component.
Presented in this paper is a framework for the design of distributed directory systems in internetwork, international CBMS environments. The objective is to provide the requisite mechanisms for mapping from user-oriented naming standards to system-oriented addresses. First a model is introduced to specify the role of directory systems in CBMS environments and to determine which names and addresses are present in such environments. Functional models are then used to illustrate general design criteria for the implementation of distributed directory systems.
Jose J. Garcia Luna Aceves, Franklin F. Kuo

The Demand and Supply of Telematic Services in Portugal

Abstract
The first part of this contribution quantifies and classifies the computer installations in Portugal, and points out their geographical distribution. We then describe the characteristics of the tradicional data communication circuits provided by the Portuguese PTT.
The portuguese packet switching public data network, Telepac, is then described. A mention is made of some national contributions to that network. Finally, some future telematic services that might be offered by the Portuguese PTT are mentioned.
Júlio A. Cardoso, Jorge C. Alves

Network Development

Frontmatter

The UNIVERSE project

Abstract
The introduction of small dish satellite services based on broadcast geostationary satellites has led to a number of experiments designed to exploit the novel features of such a network. The DARPA Wideband Experiment in the US, Project Nadir in France, a proposed German experiment and project UNIVERSE in the UK are all active in this area. These novel features include very low error rates, broadcast transmission, very high data rates but also long delays.
C. J. Adams

Performance Comparison of Local Area Network Architectures

Abstract
There are two major styles of architecture for local area networks
1)
Bus Networks;
 
2)
Ring Networks.
 
which themselves are divided into several sub-classes within each major aivision. This paper briefly outlines models of the performance of Ethernet, Cambridge Ring and token ring architectures. The response time achievable using the different architectures is studiea both as a function of network length and as the rate of message submission increases.
Peter J. B. King

Convergence of LAN and Digital Telephone Exchange Systems

Abstract
This paper explains the value of integrating all voice and data services under the umbrella of the open systems interconnect (OSI) architecture which is being developed by the International Standards Organisation.
Jack Houldsworth

Network Management

Frontmatter

Network Management in a Service Environment

Abstract
The South West Universities Regional Computer Centre (SWURCC) was established in 1975 to meet the needs of the ‘big batch’ users at University College Cardiff, the University of Wales Institute of Science and Technology and the Universities of Exeter, Bath and Bristol. All user work reaches SWURCC’s twin ICL 2980 system via X.25 links. Apart from the mixed scientific batch workload a user terminal service based on X.29 offers editing and job submission facilities. Our basic philosophy includes the provision of a consistent and reliable user interface, comprehensive documentation, high quality software, adoption of standards and a strong inclination towards manufacturer supplied and supported solutions rather than the ‘do it yourself’ approach.
J. R. Brookes, M. O. Johnson, J. S. Thomas

The Transition towards Open Working

Abstract
The computer centres of universities and research institutions in the United Kingdom are being connected together according to OSI principles. Users are already able to access a variety of computer systems from the same terminal and the implementation of non-proprietary standards to transfer files and jobs in progress. This paper outlines the motivation behind the project and its overall structure. It discusses the Choice of standards in advance of internationally ratified specifications and the mechanisms for getting implementations of than on a number of different types of computer. The process of transition towards the new standards currently in progress at a large national centre is also described.
R. A. Rosner

The Management of the SERC Network

Summary
The SERC network is a large X25 network with 11 exchanges and about 160 DTEs. The network and its developement is described elsewhere in this series of papers. Managing a network of this size is a substantial and complicated task. Initially there was little or no management but now considerable effort is going into providing the various facilities needed. There is still considerable developement to do. The literature on ‘practical’ network management is sparse and suitable equipment is even sparser.
P. Bryant

Computational Techniques for Evaluation of Communication System Performance

Summary
In this paper we review some techniques for evaluating the performance of digital communication systems operating on channels characterized by additive Gaussian noise as well as linear and nonlinear distortions. The parameters considered are the error probability, the minimum distance (useful when a maximum-likelihood sequence receiver is used), the cutoff rate (useful when coding has to be used on the channel), and the spectral occupancy (useful when two or more users share the same frequency band). The emphasis is placed on the computational algorithms that allow these parameters to be evaluated numerically.
Ezio Biglieri

Protocols & Secure Systems

Open Systems Interconnection Protocols

Abstract
The concept of Open Systems Interconnection (OSI) has now been in existence for several years. The aim of OSI was (and is) to allow the standardization of a small set of general-purpose protocols which would make possible the widespread interconnection of heterogeneous computer systems. The protocols are being developed according to a Reference Model which partitions communications into seven layers. This has permitted parallel development of the protocols for the different layers. The first protocols to emerge are for the transport and session layers. These protocols are crucial to the success of OSI, providing as they do the network- and application- independent connection of systems. The capabilities provided by these protocols and their history, functionality, and status are examined.
Douglas Steedman

Services for Supporting Application Layer Protocols for Distributed Database Systems

Abstract
A kernel providing transaction oriented communication services is proposed as an interface module between distributed database systems and generalized communication systems. In order to support an easy and efficient implementation of application layer protocols for distributed database systems, this kernel provides high level services for transaction oriented message exchange, commit processing, etc. It is argued that the underlying generalized communication system should provide services for connectionless data transmission, multicast and the surveillance of remote sites.
B. Walter, K. Rothermel

An Overview of Data Encipherment in the Public Domain

Abstract
This paper traces the development of data encipherment in the public domain, examining the available algorithms, and discusses the way in which standards for applications of data encipherment are developing. It also serves as an introduction to the two associated papers on key management and data signature.
Wyn L. Price

Key Management for Data Encipherment

Abstract
Key management is of vital concern in designing a secure data handling system. Various methods have been suggested, but there is, as yet, no move towards formulating a standard. The paper examines four possible systems and shows how each has important areas of application.
Wyn L. Price

Authentication and Signature for Message Handling

Abstract
In many data communication applications it is desirable to be able to prove receipt and authenticity of a transmitted document. Encipherment techniques are available which make this possible. The paper gives an outline of the principles involved.
Wyn L Price

Delegates ‘Short’ Papers

Frontmatter

The BIBNETT 2 project

Abstract
The BIBNETT 2 project is a joint research project where the main goal is to clarify whether system-to-system communication between independently developed information systems, running on different types of computers, is economic and technical feasible in Norway. Four systems will be connected via an OSI network.
Liv A. Holm

Telplanner(TM): An Expert System for Planning Communications Services

Abstract
A case study, “Certain aspects of telecommunication transport tradeoffs”, was done for the International Telecommunication Union (1) in conjunction with their “Telecommunications for Development” project (2). The main purpose of this study was to see if a useful figure of merit for communications, similar to that for computers, could be developed.
Herbert Ohlman

On the Influence of the Interaction between Entities for Protocol Description

Abstract
We will follow the architecture for OSI proposed by ISO. Within this architecture, protocols describe the rules and formats of communication among homogeneous entities; they are independent of interaction properties of entities with entities in adjacent layers. The description of functions of the entity for the protocol of the layer N, if it is to be complete, includes the mechanisms used for the interaction with entities in adjacent layers N+1 and N−1. Sane of the factors that are important for the consideration of interaction rules are resource assignement for interaction among entities, its consequence in through put at the service access point N and N−1 and the utilisation of resources within the entity N.
Fabio R. Mendez

Communications Services and Distributed System Operations

Abstract
The ISO Open Systems Interconnection Model has provided the basis for discussions at successive NATO Advanced Study Institutes. As implementations of systems exploiting the lower levels of the ISO OSI model become available commercially, the spotlight is tending to turn more toward the shortcomings which make the productive interconnection of heterogeneous computer systems elusive. The diminishing cost of computers, coupled with their increasing power, is inducing an explosion of diverse small systems, many of which are being used for the manipulation of valuable corporate data. The rapid growth of distributed systems is not wholly without risk and, together with today’s focus on information technology, a need for a professional information engineer is becoming apparent. The questions below were offered as a starting point for discussion on some of these issues.
Laurence Wing

Telecommunications-Related Information Services the User’s Point of View

Summary
In many countries the PTT’s have introduced new non-voice services. Most of them to face unexpected difficulties, the worst of which laying in non-technical problem areas.
For the end-user telephony is an integral, rather uncomplicated information service with clear possibilities, limitations, costs, benefits and protocols. In most cases one single supplier is responsible for maintaining a good quality of the entire service.
Non-voice telecommunication services are mostly just an element in a more comprehensive information service, which, in the end-users perception, is much more complex. Very often the quality of each element is well-defined but nobody seems to be responsible for the overall quality of the whole.
This paper sides with the user’s viewpoint on new telecommunications-related information services, identifying a few problem areas and discussing which approaches could be appropriate there.
Jan van den Burg

Backmatter

Weitere Informationen