Principles of Information Systems Eighth Edition Chapter 1 An Introduction to Information Systems.
Principles of Information Systems - Chapter 13
description
Transcript of Principles of Information Systems - Chapter 13
Principles of Information Systems, Sixth Edition
Systems Design, Implementation, Maintenance, and Review
Chapter 13
Principles of Information Systems, Sixth Edition
Principles and Learning Objectives
• Designing new systems or modifying existing ones should always be aimed at helping an organization achieve its goals.
– State the purpose of systems design and discuss the differences between logical and physical systems design.
– Outline key steps taken during the design phase.– Describe some considerations and diagrams used during
object-oriented design.– Define the term RFP and discuss how this document is used
to drive the acquisition of hardware and software.– Describe the techniques used to make systems selection
evaluations.
Principles of Information Systems, Sixth Edition
Principles and Learning Objectives
• The primary emphasis of systems implementation is to make sure that the right information is delivered to the right person in the right format at the right time.
– State the purpose of systems implementation and discuss the various activities associated with this phase of systems development.
– List the advantages and disadvantages of purchasing versus developing software.
– Discuss the software development process and some of the tools used in this process, including object-oriented program development tools.
Principles of Information Systems, Sixth Edition
Principles and Learning Objectives
• Maintenance and review add to the useful life of a system but can consume large amounts of resources. These activities can benefit from the same rigorous methods and project management techniques applied to systems development.
– State the importance of systems and software maintenance and discuss the activities involved.
– Describe the systems review process.
Principles of Information Systems, Sixth Edition
Systems Design
Principles of Information Systems, Sixth Edition
Top Uses for New Systems in Various Industries
Principles of Information Systems, Sixth Edition
Logical Design
• Output design: types, format, content, frequency• Input design: types, format, content, frequency• Process design: calculations, comparisons,
manipulations• File & database design: capabilities and organization• Telecommunications design: high-level network
description• Procedures design: automated & manual• Controls & security design• Personnel & job design
Principles of Information Systems, Sixth Edition
Physical Design
• Hardware design• Software design• Database design• Telecommunications design• Personnel design• Procedures and controls design
Principles of Information Systems, Sixth Edition
Special System Design Considerations
• Procedures for signing on• Interactive processing • Interactive dialog• Preventing, detecting, and correcting errors
Principles of Information Systems, Sixth Edition
The Scope of Design
Principles of Information Systems, Sixth Edition
Procedures for Signing On
Principles of Information Systems, Sixth Edition
Interactive Processing
Principles of Information Systems, Sixth Edition
Emergency Alternate Procedures & Disaster Recovery
• Telecommunications backup• Personnel backup• Hardware backup• Software and database backup
Principles of Information Systems, Sixth Edition
Hardware Backup
• Disaster recovery plans• Hot site• Cold site
Principles of Information Systems, Sixth Edition
Software & Database Backup
• Selective backups• Incremental backups• Image log
Principles of Information Systems, Sixth Edition
Preventing, Detecting, and Correcting Errors
Principles of Information Systems, Sixth Edition
Object-Oriented Design
Principles of Information Systems, Sixth Edition
Systems Controls
• Deterrence controls• Input controls• Processing controls• Output controls• Database controls• Telecommunications controls• Personnel controls
Principles of Information Systems, Sixth Edition
Request for Proposal
Principles of Information Systems, Sixth Edition
Financial Options
Principles of Information Systems, Sixth Edition
Cost/Benefit Analysis
Principles of Information Systems, Sixth Edition
Cost/Benefit Analysis
Principles of Information Systems, Sixth Edition
Evaluation Techniques
• Group consensus• Benchmark tests• Cost/benefit analysis• Point evaluation
Principles of Information Systems, Sixth Edition
The Final Evaluation
Principles of Information Systems, Sixth Edition
Point Evaluation
Principles of Information Systems, Sixth Edition
Freezing Design Specifications
Principles of Information Systems, Sixth Edition
The Design Report
Principles of Information Systems, Sixth Edition
Systems Implementation
Principles of Information Systems, Sixth Edition
Systems Implementation
Principles of Information Systems, Sixth Edition
Acquiring Software: Make or Buy Software?
• Externally developed software– Lower cost – Lower risk– Ease of installation
Principles of Information Systems, Sixth Edition
Make or Buy Software
• Steps– Review needs, requirements, and costs– Acquire software– Modify or customize software– Acquire software interfaces– Test and accept the software– Maintain the software
Principles of Information Systems, Sixth Edition
In-House Developed Software
• Chief programmer teams • The programming life cycle
Principles of Information Systems, Sixth Edition
Chief Programmer Teams
Principles of Information Systems, Sixth Edition
The Programming Life Cycle
Principles of Information Systems, Sixth Edition
Tools & Techniques for Software Development
• Cross-platform development• Integrated development environments • CASE tools• Structured design• Structured programming• Structured walkthroughs
Principles of Information Systems, Sixth Edition
Characteristics of Structured Programming
Principles of Information Systems, Sixth Edition
Structured Design and Programming
Principles of Information Systems, Sixth Edition
Structured Design and Programming
Principles of Information Systems, Sixth Edition
Structured Walkthroughs
Principles of Information Systems, Sixth Edition
Additional Implementation Activities
• Acquiring database and telecommunication systems
• User preparation• Hiring and training IS personnel• Site preparation• Data preparation
Principles of Information Systems, Sixth Edition
Additional Implementation Activities
• Installation• Testing
– Unit testing– System testing– Volume testing– Integration testing– Acceptance testing
Principles of Information Systems, Sixth Edition
Testing
Principles of Information Systems, Sixth Edition
Start-Up Approaches
Principles of Information Systems, Sixth Edition
Start-Up Approaches
Principles of Information Systems, Sixth Edition
Systems Maintenance
Principles of Information Systems, Sixth Edition
Reasons for Maintenance
• Changes in business processes• Requests from stakeholders, users, or managers• Errors in the program• Technical and hardware problems• Corporate mergers & acquisitions• Government regulations• Changes in the operating system or hardware
Principles of Information Systems, Sixth Edition
Types of Maintenance
• Slipstream upgrade• Patch• Release• Version
Principles of Information Systems, Sixth Edition
The Financial Implications of Maintenance
Principles of Information Systems, Sixth Edition
The Relationship Between Maintenance and Design
Principles of Information Systems, Sixth Edition
Systems Review
Principles of Information Systems, Sixth Edition
Types of Review Procedures
Principles of Information Systems, Sixth Edition
Factors to Consider During Systems Review
• Mission• Goals• Hardware/software• Database• Telecommunications• IS personnel• Control
• Training• Costs• Complexity• Reliability• Efficiency• Response time• Documentation
Principles of Information Systems, Sixth Edition
Summary• Systems design - preparing detailed design needs for a new
system or modifying an existing system
• Systems implementation – installing the system and making everything, including users, ready for its operation
• Software - can be purchased from vendors or developed in-house - a decision termed the make-or-buy
• Systems maintenance - involves checking, changing, and enhancing the system to make it more useful in obtaining user and organizational goals
• Systems review - the process of analyzing systems to make sure that they are operating as intended