Essential System Requirements: A Practical Guide to Event-driven Methods (Addison-Wesley Information Technology Series) [Englisch] [Taschenbuch]

It is a costly fact that a large percentage of information system development projects fail--ending up over budget, behind schedule, or so poorly designed that they remain unused. Essential System Requirements targets the discovery and definition of critical system requirements in the analysis phase of system development--where good design is vital to the success of a project. This book explores a design methodology that involves users early on to describe essential business events. These events then partition the system response into logical, more easily managed segments. The result is a conceptual model that reflects real business needs and accelerates the entire delivery process. Essential System Requirements assembles the information developers need to understand and apply this methodology and condenses it into a concise and practical guide. This book reviews the development life cycle, highlights the importance of requirements, and introduces the concept of business events.It provides a detailed description of experience-based techniques and methods to analyze, specify, and partition the requirements of an information system, covering project tasks and procedures, system behavior, data and process modeling techniques, and the transition to physical design. Inside you will also find a clear description of function point estimation, a promising method of estimating the time and cost of future software projects based on system requirements. In addition, Essential System Requirements shows you how responses to business events can be partitioned across object classes, focusing on the application of use cases in event-driven requirements analysis. Also featured: *A middle-out strategy that is similar to the way humans typically categorize and classify objects. *The need for rapid development combined with a sound, scalable software architecture (RAAD). *A discussion of the changing world market and the related need for adaptive business systems. *The impact of making a major paradigm switch in a corporate software environment and ways to move to an event-driven approach.*The specification of a system response to an event using a business scenario, data model, process model, entity life cycle, and event/entity interaction (CRUD) matrix. With this book as your guide, you will have at hand proven techniques for defining the systems your clients want and setting the stage for a smoother, faster, more easily managed development process. 0201616068B06012001

It is a costly fact that a large percentage of information system development projects fail--ending up over budget, behind schedule, or so poorly designed that they remain unused. Essential System Requirements targets the discovery and definition of critical system requirements in the analysis phase of system development--where good design is vital to the success of a project. This book explores a design methodology that involves users early on to describe essential business events. These events then partition the system response into logical, more easily managed segments. The result is a conceptual model that reflects real business needs and accelerates the entire delivery process. Essential System Requirements assembles the information developers need to understand and apply this methodology and condenses it into a concise and practical guide. This book reviews the development life cycle, highlights the importance of requirements, and introduces the concept of business events.It provides a detailed description of experience-based techniques and methods to analyze, specify, and partition the requirements of an information system, covering project tasks and procedures, system behavior, data and process modeling techniques, and the transition to physical design.

Inside you will also find a clear description of function point estimation, a promising method of estimating the time and cost of future software projects based on system requirements. In addition, Essential System Requirements shows you how responses to business events can be partitioned across object classes, focusing on the application of use cases in event-driven requirements analysis. Also featured: *A middle-out strategy that is similar to the way humans typically categorize and classify objects. *The need for rapid development combined with a sound, scalable software architecture (RAAD). *A discussion of the changing world market and the related need for adaptive business systems. *The impact of making a major paradigm switch in a corporate software environment and ways to move to an event-driven approach.*The specification of a system response to an event using a business scenario, data model, process model, entity life cycle, and event/entity interaction (CRUD) matrix. With this book as your guide, you will have at hand proven techniques for defining the systems your clients want and setting the stage for a smoother, faster, more easily managed development process.

0201616068B06012001

This book provides a toolbox of event-driven design methods.
Some methodologies are more complex than the system requirements they are supposed to help define. This book provides a toolbox of methods that are concise and based on intuitive business events. Not all will be used on every project but can be applied when they bring value to the requirements analysis process. I believe these methods can give the analysis team an edge when facing the very important task of building a system that is on target with user expectations.

When one sets out to write a guide, he/she must focus on conciseness and thus some of the ideas may not get the full attention they deserve. There is also a density that comes from trying to pack so much into a small space. The result can be that the reader comes away without having focused on some of the more important concepts. I have summarized many of the key concepts below for the reader's awareness as he/she studies the book.

* Developers must be encouraged to “get it right the first time” to minimize construction and post implementation repair.

* Requirements analysis is the most important part in the software development process and software developers, as a group (with exceptions of course), define requirements poorly.

* Everyone up and down the development chain can do their part well but the system can still be a failure (does not meet business expectations) because of poor requirements.

* The software development life cycle is foundational; it is not necessarily an effective roadmap to the development process.

* An iterative, middle out approach to requirements definition with a toolbox of methods is more natural and typically more effective than a stepwise, waterfall approach based on the life cycle.

* Events provide an intuitive, real-world perspective of the user interface and system response and provide the structure for an iterative approach.

* All requirements are not equal; events provide for high-level management of the identification and prioritization of essential functionality.

* During requirements analysis, events help keep the business and development teams focused on ‘what’ the system must do rather than ‘how’ it will be accomplished, and provide a vehicle for communication between business users and analysts.

* System requirements evolve and change and events help the development team manage this process.

* Events and their respective scenarios reveal key business users, required processing, and real-world objects, bring the user on board early, and encourage user ownership of the system.

* Events are pervasive across the development life cycle and provide a basis for system architecture (process and data distribution) and testing.

* Events provide an architecture for RAAD (Rapid Architected Application Development).

* An event is the basic element of a use case; use cases can be used with traditional system requirements analysis as well as with an object orientation.

Bill Wiley is a consultant specializing in event-based methodology and system requirements definition. He has twenty-five years of experience in virtually all aspects of application development, spanning a wide range of systems, user groups, corporate environments, and hardware platforms. He spent eight years at the Johnson Space Center in Houston and has sixteen years of experience with manufacturing systems. His consulting experience includes methodology training and the application of event-driven analysis and design methods; he has also facilitated joint design sessions. Mr. Wiley most recently researched the application of various event-based methods during a nine-year tenure as an assistant professor of information systems at Taylor University. 0201616068AB04062001