Chapter01 1

McGraw-Hill/Irwin Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

Chapter 1

The Systems Development Environment

The Systems Development Environment

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Learning ObjectivesLearning ObjectivesLearning ObjectivesLearning Objectives

• Understand the concept of systems analysis and design as a disciplined approach to development

• Become familiar with the evolution of systems analysis and design

• Understand the concepts of data-centricity and process-centricity

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• Describe the various roles and responsibilities in systems development

• Explain the types of skills necessary to be a successful systems analyst

• Review the different classes of information systems

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• Develop an initial understanding of the phased life-cycle approach to systems development

• Identify two alternative approaches to systems development beyond the life-cycle approach

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Systems Analysis and DesignSystems Analysis and DesignSystems Analysis and DesignSystems Analysis and Design

• Definition– A structured process that is employed in

the development of information system

– Systems analysis activities– Systems design activities

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• Systems analysis activities– Focused on determining the nature and

domain of the business problem– Concerned with issues such as problem

identification, solution alternatives, solution requirements, organizational goals, etc.

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• Systems design activities– Focused on the final design specification

and the construction, development, and implementation of the solution proposed during analysis and deemed best among any alternatives available

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A Disciplined ApproachA Disciplined ApproachA Disciplined ApproachA Disciplined Approach

• Methodologies– A multi-step approach to the analysis,

design, and delivery of an IS

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A Disciplines ApproachA Disciplines ApproachA Disciplines ApproachA Disciplines Approach

• Tools– Computer programs that are designed to

facilitate the wide variety of techniques and activities to be conducted during a complete analysis and design scenario

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A Disciplines ApproachA Disciplines ApproachA Disciplines ApproachA Disciplines Approach

• Techniques– Processes that are followed to ensure that

the analysis being performed is accurate, comprehensive, and comprehensible to others

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Modern SAD Modern SAD Modern SAD Modern SAD

• The evolution of software development and application design began with a focus on the process, evolved to a focus on the data, and has now come to an understanding of the need to consider both elements in the design of a modern IS

• Data-Centric and Process-Centric development approaches

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Table 1-1. Comparison of the Data-Centric and Process-Centric Development Approaches

Data-Centric Approach Process-Centric Approach What data does the system need?

What is the system supposed to do?

Tends to have an enduring design stability due to low volatility in organizational data needs.

Design stability is necessarily limited due to constant changes in business processes.

The file structure is enterprise dependent.

The file structure is application dependent.

Data redundancy is generally limited and controlled.

Data redundancy is generally massive and uncontrolled.

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Systems Analysis as a ProfessionSystems Analysis as a ProfessionSystems Analysis as a ProfessionSystems Analysis as a Profession

• Career and Job Opportunities

• Typical career paths for Systems Analyst

• Professional Societies and Standards of Practice (ACM)

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Analyst Role Relationship to Organization

Programmer/Analyst Employee of the organization

Systems Analyst Employee of the organization

Independent Analyst Contractor to the organization

Outsource Provider Employee of outsourcing contractor

Systems Consultant Contractor to the organization

Software developer Manufacturer or supplier of software

Table 1-2. Typical Analyst-Organization Relationships

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Typical Systems Analyst Duties Typical Systems Analyst Duties and Responsibilitiesand ResponsibilitiesTypical Systems Analyst Duties Typical Systems Analyst Duties and Responsibilitiesand Responsibilities

• Entry-Level Systems Analyst– Working under the supervision of a more

senior staff member, junior systems analysts may be responsible for any of the following:

• investigate requirements, information flow, processes, etc.,

• produce documentation specifying logical information flows and processes,

• perform technical calculations for input to project budgets and monitor budget,

• convert limited parts of a logical specification into a physical design, and/or

• construct, interpret and execute test plans of a limited scope.

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• Full Working Systems Analyst – At this level, you will be performing the systems

analyst job without supervision. – You may be responsible for the supervision of

other staff on a project. In addition you may be responsible for small projects or portions of larger projects, and you may have to:

• specify logical information flow, processes, data objects and dialogues,

• produce technical and descriptive documentation, • devise, construct and interpret test plans and ensure

proper execution, and/or• prepare estimates, monitor budgets and report

constraints.

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• Intermediate System Analyst – As the intermediate systems analyst, you

will be expected to supervise staff. You may also be required to:

• supervise performance of team players in reaching objectives,

• plan and schedule small work teams, prepare projects less than 3 person-months in size,

• develop service level agreements and business plans with clients, and/or

• devise outlines or models of systems solutions.

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• Senior Systems Analyst – As the senior systems analyst you will most likely

be involved in planning, conducting and supervising complex informatics assignments. You will also be involved in designing and applying new methods and procedures and supervising staff. Your job could also require you to:

• plan and manage multiple projects, • lead systems implementation throughout systems life

cycle, and/or• manage and maintain operations of mission-critical

systems.

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The Roles and Responsibility in The Roles and Responsibility in Systems DevelopmentSystems DevelopmentThe Roles and Responsibility in The Roles and Responsibility in Systems DevelopmentSystems Development

• Client and System Users– ultimately benefit from the development

effort– directly involved in either the use of system

itself or the information and reports generated by it

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• IS management– directly involved in the daily activities of the

IS project– responsible for the allocation of resources

to the project– responsible for the establishment of criteria

necessary to determine the success of the development effort

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• Systems Analysts– key individuals in the system development

process– can act as consultant, a staff expert, a

project manager, or even a change agent

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• Application programmers– the labor-intensive nature of manual

programming became untenable and often cost-ineffective

– with CASE tools, the modern programmers can spend more time on finalization, optimization, and integration of the code into the IS under development

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• IS Support Personnel– Vendors and Technologists– Database Administrators– Network Administrators– Audit and Security– IT Steering Committee

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Skill Set for Systems AnalysisSkill Set for Systems AnalysisSkill Set for Systems AnalysisSkill Set for Systems Analysis

• Technical Skills– A working knowledge of the technology in

the areas of database management, data networks, telecommunications, operating systems, distributed architectures, object technology, languages and protocols, etc.

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• Analytical Skills– A systems analyst is a problem solver.– The ability to examine a complex set of

components without losing sight of the bigger picture is essential to an analyst’s success.

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• Managerial skills– A successful analyst is a team player.– Includes business domain knowledge,

resource and project management, assessment and management of risk, and management of change.

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• Interpersonal Skills– A successful analyst is a good

communicator.– Includes the ability to question, listen, and

observe.– Effectively conduct oral and written

presentations; facilitate groups; and be a team player.

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Types of Information SystemsTypes of Information SystemsTypes of Information SystemsTypes of Information Systems

• Transaction Processing Systems (TPS)– automate the capture and recording of

information about business activities (transaction)

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Figure 1-3. Transaction Processing Systems Can Support a Management Information Systems

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• Management Information Systems (MIS)– Accepts input from a TPS and transforms it

into meaningful format.– Is considered an important management

resource, and the opportunities for analysis and design in this area are endless.

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• Decision Support Systems– Provides support to the decision process.– Is a powerful tools and is rapidly becoming

an integral component within the realm of organizational information systems.

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• Expert Systems– Imitates reasoning processes based on the

concept of information fit used by human experts in solving specific knowledge domain problems

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• Executive Information Systems– Facilitates and supports the information

and decision-making needs of senior executives by providing easy access to internal and external information.

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• Office Automation and Workgroup Management Systems– Facilitates the analysis and dissemination

of information throughout the organization.

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• Web-based Systems– Supports business-to-business and

business-to-consumer electronic commerce, data management, customer relations, supply chain management, and enterprise resource management.

– Systems analysts will be increasingly expected to provide Web-based solutions to the business problems of tomorrow.

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Figure 1-4. Relationships between various System Types and Organizational Level

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SDLCSDLCSDLCSDLC

• Composed of a common set of phases and activities serve to structure and guide the development process

• Also called Waterfall Model

• Figure 1-5

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Figure 1-5. The Systems Development Life Cycle

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Overview of Phases and ActivitiesOverview of Phases and ActivitiesOverview of Phases and ActivitiesOverview of Phases and Activities

• Preliminary investigation phase– Identification and selection of a

development project– Initiation of a preliminary investigation to

determine project feasibility– Formation of a project team– Development of the project plan

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• Analysis Phase– Study of the organization’s processes,

procedures, and systems

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• Logical Design Phase– Revise and refine the logical model– Implementation independent

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• Physical Design Phase– Convert logical model into physical

specification

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• Implementation Phase– Installation of the physical model– End user training

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• Maintenance Phase– Detailed modifications to the new system

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Drawbacks to the SDLCDrawbacks to the SDLCDrawbacks to the SDLCDrawbacks to the SDLC

• Sequential process

• Time consuming

• Maintenance cost

• Figure 1-6

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Figure 1-6. Relative Cost of Fixing an Error in a Development Project

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Alternative Development ApproachesAlternative Development ApproachesAlternative Development ApproachesAlternative Development Approaches

• Object-oriented Analysis and Design (OOAD)– Combination of process- and data-oriented

approaches– Object– Reusability

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Alternative Development ApproachesAlternative Development ApproachesAlternative Development ApproachesAlternative Development Approaches

• Rapid Application development (RAD)– Rely on the use of CASE tools and

prototyping approach

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Chapter SummaryChapter SummaryChapter SummaryChapter Summary

• Systems analyst represents an expert blend of technical, analytical, managerial, and interpersonal skills

• Modern information systems development involves several structured approaches

McGraw-Hill/Irwin Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

Chapter 1

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Education

Chapter01 1