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S A Springer
The Business Opportunity
Advantages of Client/Server Computing
Components of Client/Server ApplicationsThe Client
Components of Client/Server ApplicationsThe Server
Components of Client/Server ApplicationsConnectivity
Client/Server Systems DevelopmentSoftware
Client/Server Systems DevelopmentHardware
Client/Server Systems DevelopmentService and Support
Client/Server Systems DevelopmentTraining
The Future of Client/Server Computing
IBM/Apple Joint Venture
Electronic Document Management Standards
Steven L. Guengerich is the President of BSG Education, a unit of
client/server systems integration specialists, BSG Corporation. He has more than 12 years experience in the strategic planning for emerging information technologies and migration to client/server, network computing systems. He is the author/coauthor for several books, including Downsizing Information Systems (Sams, 1992), and was the cofounder of BSG's NetWare Advisor.
Patrick N. Smith is Senior Vice President and Chief Technology Officer of SHL Systemhouse, Inc., and also serves as its senior technologist. He is widely recognized for his ability to communicate complex technological issues in a manner that leads
management to understand the potential and opportunity to use technology to improve business effectiveness. During the 25 years he has been involved in the computer industry, Smith also has worked as manager of technical support and as a lecturer in
computer science at a major university.
A fundamental shift has occurred in the way businesses go about using information systems for their competitive advantage. New techniques, such as business process reengineering, are leading to systems reengineering. And as businesses decentralize and
downsize, information systems follow suit. In the years ahead, we believe analysts will look back at this as a time when computing really was invented.
Along with the tremendous potential, however, comes tremendous confusion and chaos in the marketplace. Open systems, object orientation, graphical user interfaces, UNIX, OS/2, CASE, database, and superserversthese are terms that can impact
information systems choices in various ways. But in today's rapidly changing business and computing environments, how do you decide which solution is best for your needs? And how do you go about implementing that solution?
This book was written to provide answers to these and similar questions. As one would expect, the information in Client/Server Computing comes from years of experience and first-hand implementation of new technologies. Both Patrick Smith, Chief
Technology Officer of SHL Systemhouse, Inc. and Steve Guengerich, President of BSG Corporation, are hands-on integrators and established technical authors and series editors. Their knowledge and the knowledge from the professionals in their respective
systems integration companies, as well as many other colleagues in the client/server computing industry, is distilled into the pages of Client/Server Computing.
We hope you gain a better understanding of and appreciation for the marvelous possibilities of this new computing paradigm as you read Client/Server Computing, and that you feel better prepared to ride the fundamental shifts in business and
computing throughout the next several years.
Steven G. Papermaster
Chairman and CEO, BSG
The client/server computing model defines the way successful organizations will use technology during the next decade. It is the culmination of the trend toward downsizing applications from the minicomputer and mainframe to the desktop. Enabling
technologies, such as object-oriented development and graphical user interfaces (GUIs), will liberate the users and owners of information to use technology personally and directly. Users will no longer need continual assistance from professional
information systems (IS) personnel to create and store their business data.
The big losers in this change will be traditional vendors and integrators of minicomputer-based solutions. Forrester Research Inc., a reputable computer industry market research firm, routinely surveys the U.S. Fortune 1000 companies. Forrester
projects that by 1993 the client/server market will account for $29 billion in sales. The pervasiveness of this technology throughout organizations dictates that all management levels understand the concepts and implications of client/server computing.
Information systems (IS) professionals must understand these concepts and implications, as well as the detailed architectural issues involved, in order to be in a position to offer liberating client/server solutions to their users. IS professionals who do
not understand these concerns will be relegated forever to a maintenance role on existing systems.
To address both audiences, this book introduces each chapter with an executive summary. In some of the later chapters, this alone may provide the necessary detail for most non-IS professionals. IS professionals will find the additional detail is
included in latter parts of each chapter to explain the technology issues more fully.
Extensive use of charts and other graphics enables these materials to be used as part of internal presentations and training.
Patrick N. Smith
SHL Systemhouse, Inc.
We would like to take this opportunity to thank the many organizations and individuals we have worked with over the past 25 years for the opportunity to experiment and learn on their behalf. The City and County of Los Angeles, in particular, have been
the source of much recent experience. Their willingness to look for world-class solutions to their business problems has allowed us to gain substantial insight into the role of technology in reengineering the business process. Many members of the
Systemhouse Technology Network have contributed directly to this book. Gord Tallas deserves particular credit and thanks for the work he did in pulling together the sample projects in Appendix A. June Ashworth applied her considerable skill and patience in
developing the diagrams. Thanks also go to Andy Roehr, Sam Johnson, Eric Reed, Lara Weekes,and Nada Khatib, BSG, who helped with the final manuscript. Finally, we must thank our families for their patience and assistance in getting this book written.
All terms mentioned in this book that are known to be trademarks or service marks have been appropriately capitalized. Sams Publishing cannot attest to the accuracy of this information. Use of a term in this book should not be regarded as affecting
the validity of any trademark or service mark.
In a competitive world it is necessary for organizations to take advantage of every opportunity to reduce cost, improve quality, and provide service. Most organizations today recognize the need to be market driven, to be competitive, and to demonstrate
A strategy being adopted by many organizations is to flatten the management hierarchy. With the elimination of layers of middle management, the remaining individuals must be empowered to make the strategy successful. Information to support rational
decision making must be made available to these individuals. Information technology (IT) is an effective vehicle to support the implementation of this strategy; frequently it is not used effectively. The client/server model provides power to the desktop,
with information available to support the decision-making process and enable decision-making authority.
The Gartner Group, a team of computer industry analysts, noted a widening chasm between user expectations and the ability of information systems (IS) organizations to fulfill them. The gap has been fueled by dramatic increases in end-user comfort with
technology (mainly because of prevalent PC literacy); continuous cost declines in pivotal hardware technologies; escalation in highly publicized vendor promises; increasing time delays between vendor promised releases and product delivery (that is,
"vaporware"); and emergence of the graphical user in terface (GUI) as the perceived solution to all computing problems.
In this book you will see that client/server computing is the technology capable of bridging this chasm. This technology, particularly when integrated into the normal business process, can take advantage of this new literacy, cost-effective technology,
and GUI friendliness. In conjunction with a well-architected systems development environment (SDE), it is possible for client/server computing to use the technology of today and be positioned to take advantage of vendor promises as they become real.
The amount of change in computer processing-related technology since the introduction of the IBM PC is equivalent to all the change that occurred during the previous history of computer technology. We expect the amount of change in the next few
years to be even more geometrically inclined. The increasing rate of change is primarily attributable to the coincidence of four events: a dramatic reduction in the cost of processing hardware, a significant increase in installed and available processing
power, the introduction of widely adopted software standards, and the use of object-oriented development techniques. The complexity inherent in the pervasiveness of these changes has prevented most business and government organizations from taking full
advantage of the potential to be more competitive through improved quality, increased service, reduced costs, and higher profits. Corporate IS organizations, with an experience based on previous technologies, are often less successful than user groups in
putting the new technologies to good use.
Taking advantage of computer technology innovation is one of the most effective ways to achieve a competitive advantage and demonstrate value in the marketplace. Technology can be used to improve service by quickly obtaining the information necessary
to make decisions and to act to resolve problems. Technology can also be used to reduce costs of repetitive processes and to improve quality through consistent application of those processes. The use of workstation technology implemented as part of the
business process and integrated with an organization's existing assets provides a practical means to achieve competitive advantage and to demonstrate value.
Computer hardware continues its historical trend toward smaller, faster, and lower-cost systems. Competitive pressures force organizations to reengineer their business processes for cost and service efficiencies. Computer technology trends prove to
leading organizations that the application of technology is the key to successful reengineering of business processes.
Unfortunately, we are not seeing corresponding improvements in systems development. Applications developed by inhouse computer professionals seem to get larger, run more slowly, and cost more to operate. Existing systems consume all available IS
resources for maintenance and enhancements. As personal desktop environments lead users to greater familiarity with a GUI, corporate IS departments continue to ignore this technology. The ease of use and standard look and feel, provided by GUIs in personal
productivity applications at the desktop, is creating an expectation in the user community. When this expectation is not met, IS departments are considered irrelevant by their users.
Beyond GUI, multimedia technologies are using workstation power to re-present information through the use of image, video, sound, and graphics. These representations relate directly to the human brain's ability to extract information from images far
more effectively than from lists of facts.
Accessing information CAN be as easy as tapping an electrical power utility. What is required is the will among developers to build the skills to take advantage of the opportunity offered by client/server computing.
This book shows how organizations can continue to gain value from their existing technology investments while using the special capabilities that new technologies offer. The book demonstrates how to architect SDEs and create solutions that are solidly
based on evolving technologies. New systems can be built to work effectively with today's capabilities and at the same time can be based on a technical architecture that will allow them to evolve and to take advantage of future technologies.
For the near future, client/server solutions will rely on existing minicomputer and mainframe technologies to support applications already in use, and also to provide shared access to enterprise data, connectivity, and security services. To use
existing investments and new technologies effectively, we must understand how to integrate these into our new applications. Only the appropriate application of standards based technologies within a designed architecture will enable this to happen.
It will not happen by accident.
Patrick N. Smith
with Steven L. Guengerich
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