Chapter 03 . Information Systems Development

Decision Analysis Phase

Candidate solutions evaluated in terms of: - Technical feasibility. - Operational feasibility. - Economic feasibility. - Schedule feasibility. - Risk feasibility.

Directive

A new requirement that is imposed by management, government, or some external influence.

Logical Model

A pictorial representation that depicts what a system is or does.

The PIECES Problem-solving Framework

- P - The need to improve PERFORMANCE - I - The need to improve INFORMATION (and DATA) - E - The need to improve ECONOMICS - C - The need to improve CONTROL - E - The need to improve EFFICIENCY - S - The need to improve SERVICE

System Model

A picture of a system that represents reality or a desired reality. System models facilitate improved communication between system users, system analysts, system designers, and system builders.

Opportunity

A chance to improve the organization even in the absence of an identified problem.

Scope Creep

A common phenomenon wherein the requirements and expectations of a project increase, often without regard to the impact on budget and schedule.

Gap Analysis

A comparison of business and technical requirements for a commercial application package against capabilities and features of a specific commercial application package to define requirements that cannot be met.

Statement of Work

A contract with management and the user community to develop or enhance an information system. It defines vision, scope, constraints, high-level user requirements, schedule, and budget.

Data Modeling

A data-centered technique used to model business data requirements and design database systems that fulfill those requirements.

Request for Quotation (RFQ)

A formal document that communicates business, technical, and support requirements for an application software package to a single vendor that has been determined as being able to supply that application package and services.

Request for Proposal (RFP)

A formal document that communicates business, technical, and support requirements for application software package to vendors that may wish to compete for the sale of application package and services.

Strategic enterprise plan

A formal strategic plan (3-5 years) for an entire business that defines its mission, vision, goals, strategies, benchmarks, and measures of progress and achievement. Usually, it is complemented by strategic business unit plans that define how each business unit will contribute to the enterprise plan. The information systems plan is one of those unit-level plans.

Strategic Information Systems Plan

A formal strategic plan (3-5 years) for building and improving an information technology infrastructure and the information system applications that use that infrastructure.

System Development Methodology

A formalized approached to the systems development process a standardized development process that defines a set of activities, methods, best practices, deliverables, and automated tools that system developers and project managers are to use to develop and continuously improve information systems and software.

Process Modeling

A process-centered technique popularized by the structured analysis and design methodology that used models of business process requirements to derive effective software designs for a system.

Backlog

A repository of project proposals that cannot be funded or staffed because they are a lower priority than those that have been approved for system development.

Analysis paralysis

A satirical term coined to describe a common project condition in which excessive system modeling dramatically slow progress toward implementation of the intended system solution.

System Development Process

A set of activities, methods, best practices, deliverables, and automated tools that stakeholders use to develop and continuously improve information systems and software.

Prototype

A small-scale, representative, or working model of the users' requirements or a proposed design for an information system.

Commercial Application Package

A software application that can be purchased and customized to meet business requirements of a large number of organizations or specific industry. A synonym is commercial off-the-shelf (COTS) system.

Capability Maturity Model (CMM)

A standardized framework for assessing the maturity level of an organizations' information system development and management processes and products. It consists of five levels: - Level 1 - Initial. - Level 2 - Repeatable. - Level 3 - Defined. - Level 4 - Managed. - Level 5 - Optimizing.

Problem Statement

A statement and categorization of problems, opportunities, and directive; may also include constraints and an initial vision for the solution.

Commercial Application Package Implementation Strategy

A strategy based on Commercial application package. It include(s): - Request for proposal (RFP). - Request for quotation (RFQ). - Gap analysis.

Rapid Application Development Strategy

A strategy based on Rapid application development (RAD). It include(s): - Prototype. - Time-boxing.

Creeping Commitment

A strategy in which feasibility and risks are continuously reevaluated throughout a project. Project budgets and deadlines are adjusted accordingly.

CASE repository

A system developers' database where developers can store system models, detailed descriptions and specifications, and other products of system development. Synonyms: dictionary and encyclopedia.

Rapid Application Development (RAD)

A system development strategy that emphasizes speed of development through extensive user involvement in the rapid, iterative, and incremental construction of series of functioning prototypes of a system that eventually evolves into the final system.

Model-driven Development

A system development strategy that emphasizes the drawing of system models to help visualize and analyze problems, define business requirements, and design information systems. It includes: - Process modeling. - Data modeling. - Object modeling.

Physical Model

A technical pictorial representation that depicts what a system is or does and how the system is implemented.

Object Modeling

A technique that attempts to merge the data and process concerns into singular constructs called objects. Object models are diagrams that document a system in terms of its objects and their interactions.

Sequential Development Approach

Also referred to as "waterfall development approach". It is an approach to system analysis and design that completes each phases on after another and only once.

Steering Committee

An administrative body of system owners and information technology executives that prioritizes and approves candidate system development projects.

Iterative Development Approach

An approach to systems analysis and design that completes the entire information system in successive iterations. Each iterations does some analysis, some design, and some construction. Some synonyms include "incremental" and "spiral".

Process Manager Application

An automated tool that helps document and manage a methodology and routes, its deliverables, and quality management standards. An emerging synonym is method-ware.

Project Manager Application

An automated tool to help plan system development activities (preferably using the approved methodology), estimate and assign resources (including people and costs), schedule activities and resources, monitor progress against schedule and budget, control and modify schedule and resources, and report project progress.

Application Development Environments (ADEs)

An integrated software development tool that provides all the facilities necessary to develop new application software with maximum speed and quality. A common synonym is integrated development environment (IDE).

Process Management

An ongoing activity that documents, manages, oversees the use of, and improves and organization's chosen methodology (the "process" for system development. Process management is concerned with phases, activities, deliverables, and quality standards should be consistently applied to all projects.

Problem

An undesirable situation that prevents the organization from fully achieving its purpose, goals, and/or objectives.

Constraint

Any factor, limitation, or restrain that may limit a solution or the problem-solving process.

Computer-aided Systems Engineering (CASE)

Automated software tools that support the drawing and analysis of system models and associated specifications. Some of these tools also provide prototyping and code generation capabilities. They consist of: - CASE repository. - Forward Engineering. - Reverse Engineering.

Forward Engineering

CASE tool capability that can generate initial software or database code directly from system.

Reverse Engineering

CASE tool capability that can generate initial system models from software or database code.

Presentation

Communicating findings, recommendations, and documentation for review by interested users and mangers.

Construction and Testing Phase

Construct and test system components. It includes the installation of: - Software - Purchased or custom-built. - Databases. - User and system interfaces. - Hardware. - Networks.

Respository

Databased and/or file directory where system developers store all documentation, knowledge, and artifacts for information systems or project(s).

Fact-Finding

Formal process of using research, interview, meetings, questionnaires, sampling, and other techniques to collect information about system problems, requirements, and preferences.

Design by Prototyping

Incomplete but functioning applications or subsystems (called prototypes) are constructed and refined based on feedback from users and other designers.

System Operation and Maintenance

It include(s) ongoing "system support", which includes: - Assisting users. - Fixing software defects (bugs). - Recovering the system. - Adapting the system to new requirements.

Automated Tools and Technology

It include(s): - Computer-aided systems engineering (CASE). - Application development environments (ADEs). - Process and Project Manager Applications.

Installation and Delivery Phase

It include(s): - Delivering the system into operation (production). - Delivering user training. - Delivering completed documentation. - Converting existing data.

Commercial Application Package Implementation Strategy Disadvantage(s)

It include(s): - Dependent on long-term viability of vendor. - Rarely reflects ideal solution. - Often resistance to changes business processes to adapt to software.

Documentation and presentation

It include(s): - Documentation. - Presentation. - Repository.

Cross Life-Cycle Activities

It include(s): - Fact-finding. - Documentation and presentation. - Feasibility analysis. - Process and project management.

Principles of System Development

It include(s): - Get the system users involved. - Use a problem-solving approach. - Establish phases and activities. - Document through development. - Establish standards. - Manage the process and projects. - Justify systems as capital investments. - Do not be afraid to cancel or revise scope. - Divide and conquer. - Design systems for growth and change.

Economic feasibility

It include(s): - Is the solution cost-effective?

Technical feasibility

It include(s): - Is the solution technically practical? - Does our staff have the technical expertise to design and build this solution?

Logical Design Phase

It include(s): - Logical design. - System model. - Analysis paralysis.

RAD Strategy Disadvantage(s)

It include(s): - May encourage "code, implement, repair" mentality. - Can solve wrong problem since problem analysis is abbreviated. - May discourage analysts from considering alternatives. - Stakeholders reluctant to throw away prototype. - Emphasis on speed can adversely impact quality.

Scope Definition Phase

It include(s): - Problem Statement. - Constraint. - Scope Creep. - Statement of Work.

Model-drive Development Strategy Advantage(s)

It include(s): - Requirements often more thorough. - Easier to analyze alternatives. - Design specifications often more stable and flexible. - Systems can be constructed more correctly the first time.

Framework for the Application of Systems Thinking (FAST)

It include(s): - Scope Definition. - Problem Analysis. - Requirements Analysis - Logical Design. - Decision Analysis. - Physical Design and Integration. - Construction and Testing. - Installation and Delivery.

Development Approaches

It include(s): - Sequential development approach. - Iterative development approach.

Classical Problem-solving Approach

It include(s): - Study and understand the problem, its context, and its impact. - Define the requirements that must be met by any solution. - Identify candidate solutions that fulfill the requirements, and select the "best" solution. - Design and/or implement the chosen solution. - Observe and evaluate the solution's impact, and refine the solution accordingly.

Commercial Application Package Implementation Strategy Advantage(s)

It include(s): - Systems usually implemented more quickly. - Avoids staffing required to develop in-house solutions. - Generally less expensive. - Vendor assumes responsibility for improvements and corrections. - Many business functions more similar than dissimilar for all businesses in a given industry.

Model-drive Development Strategy Disadvantage(s)

It include(s): - Time consuming. - Models only as good as users' understanding of requirements. - Reduces users' role because pictures are not software. - Can be inflexible.

RAD Strategy Advantage(s)

It include(s): - User requirements often uncertain or imprecise. - Encourages active user and management participation. - Projects get higher visibility and support. - Stakeholders see working solutions more rapidly. - Errors detected earlier. - Testing and training are natural by-products. - More natural process because change is expected.

Requirements Analysis Phase

It include(s): - What capabilities should the new system provide for its users? - What data must be captured and stored? - What performance level is expected. - What are the priorities of the various requirements.

Risk feasibility

It include(s): - What is the probability of a successful implementation using the technology and approach?

Stage change trigger(s)

It include(s): - When a system cycles from development to operation and maintenance, a conversion must take place. - At some point in time, obsolescence occurs (or is imminent) and a system cycles from operation and maintenance to redevelopment.

Operational feasibility

It include(s): - Will the solution fulfill the users' requirements? To what degree? - How long will the solution change the users' work environment? - How do users feel about such a solution?

Level 4 - Managed

Measurable goals for quality and productivity are established.

Design by Specification

Physical system model and detailed specification are produced as a series of written (or computer-generated) blueprints for construction.

Level 2 - Repeatable

Project management processes and practices established to track project costs, schedules, and functionality.

Documentation

Recording facts and specifications for a systems for current and future reference.

Level 3 - Defined

Standard system development process (methodology) is purchased or developed. All projects use a version of this process.

Level 1 - Initial

System development projects follow no prescribed process.

Level 5 - Optimizing

The Standardized system development process is continuously monitored and improved based on measures and data analysis established in the previous level.

System Life Cycle

The factoring of the lifetime of an information system into two stages: - Systems development - Systems operation and maintenance.

Time-boxing

The imposition of a non-extendable period of time, usually 60-90 days, by which the first (or next) version of a system must be delivered into operation.

Risk Management

The process of identifying, evaluating, and controlling what might go wrong in a project before it becomes a threat tot the successful completion of the project or implementation of the information system. It is driven by risk analysis or assessment.

Project Management

The process of scoping, planning, staffing, organizing, direction, and controlling a project to develop an information system at a minimum cost, within a specified time frame, and with acceptable quality.

Cost-effectiveness

The result obtained by striking a balance between the lifetime costs of developing, maintaining, and operating an information system and the benefits derived from that system. It is measured by a cost-benefit analysis.

Planned project

The result of one of the following: - Information systems strategy plan - Business process redesign.

Physical Design and Integration Phase

The translation of business user requirements into a system model that depicts a technical implementation of the users' business requirements. Common synonyms include "technical design" or "implementation model". It includes two extreme philosophies: - Design by specification. - Design by prototyping.

Logical Design

The translation of business user requirements into a system model that depicts only the business requirements and not any possible technical design or implementation of those requirements. Common synonyms include "conceptual design and "essential design".

Unplanned project

it is usually screened and prioritized by: - Steering committee of system owners and IT managers to determine which requests get approved. - Those that are not approved are "backlogged" until resources become available again.