Chapter 12: Systems Planning and Development

Management Information Systems, Sixth Edition

Chapter 12:

Systems Planning and Development

Management Information Systems, Sixth Edition 2

Objectives

• Explain the importance of and steps in IT planning

• Describe the systems development life cycle, which is the traditional approach to systems development

• Explain the challenges involved in systems development

• List the advantages and disadvantages of different system conversion strategies


Objectives (continued)

• Enumerate and explain the principles of agile systems development methods

• Be able to contribute a meaningful set of requirements when serving on a project development team for a new or modified IS

• Explain the concept of systems integration• Discuss whether IS professionals should be

certified


Planning Information Systems

• Enterprise ISs are gaining in popularity• However, they:

– Require a substantial investment

– Carry a high risk in implementation

• Successful integration of the system is vital– Must align IT strategies with the overall

organization strategies

• Careful planning of an IS implementation is necessary


Steps in Planning Information Systems

• IT planning includes several key steps:– Create a corporate and IT mission statement

– Articulate the vision for IT within the organization

– Create IT strategic and tactical plans

– Create a plan for operations to achieve the mission and vision

– Create a budget to ensure that resources are available to achieve the mission and vision



Steps in Planning Information Systems (continued)

• Mission statement: communicates the most important overarching goal of organization– Includes how the goals will be achieved

• IS mission statement: describes the role of IT in the organization– Should be compatible with the organizational

mission statement

– Includes the ideal combination of hardware, software, and networking to support the mission



• CIO develops a strategic plan for implementation of IT in the organization:– What technology will be used by employees,

customers, and suppliers

• Goals in the plan are broken down into objectives, such as:– Resources to be acquired or developed

– Timetables for acquiring and implementing resources

– Training


• Objectives are broken down to operational details

• IT planning is similar to planning of other resource acquisitions

• Growing proportion of IT funds is spent on software in recent years– More purchasing and adapting of software

– Less developing in-house software




The Benefits of Standardization in Planning

• One major goal and advantage of planning is standardization

• Benefits include:– Cost savings: better bargaining power in

purchasing and leasing hardware and software

– Efficient training: a smaller variety of software reduces employee training needs

– Efficient support: enables more staff specialization


From Planning to Development

• After planning, management must decide how to obtain the systems (usually software)

• Approaches to systems development are the same for in-house or purchased systems

• Two general approaches:– Systems development life cycle (SDLC), the

traditional approach– Nontraditional methods, including agile methods

• Prototyping: fast development of an application based on initial user requirements


The Systems Development Life Cycle

• Large ISs are conceived, planned, and developed within the systems development life cycle (SDLC) framework

• Also known as waterfall development• Consists of four major sequential phases:

– Analysis

– Design

– Implementation

– Support



Analysis

• Systems analysis: a five-step process– Investigation

– Technical feasibility study

– Economic feasibility study

– Operational feasibility study

– Requirements definition



Analysis (continued)

• Investigation– Is a system really necessary?

– Is the system, as conceived, feasible?

• Small ad hoc team usually performs a preliminary investigation by interviewing employees

• Feasibility studies: a larger analysis conducted after preliminary results indicate an IS is warranted


Analysis (continued)• Technical feasibility study:

– Determines if components exist or can be developed

– Determines if the organization has adequate hardware

• Economic feasibility study:– Determines if the new IS is economically justified

– Cost/benefit analysis: spreadsheet showing all costs and benefits of the proposed system

– Benefits must outweigh the costs over the life of the system


• Return on investment (ROI): most accurate economic analysis– Calculates the difference between the stream of

benefits and the stream of costs over the life of the system

• May be difficult to justify the cost of a new IS because many benefits are intangible and cannot be quantified in dollar terms– Examples: business intelligence (BI) and

knowledge management (KM) systems





• Operational feasibility study:– Determines how the new system will be used

• Organizational culture: general tone of the corporate environment– Must determine the new system’s compatibility

with the organizational culture

• Requirements definition: details what the system should be able to do

• System requirements: detail the functions and features expected from the new system


Design• Design: the second phase in systems development• Systems design: includes three steps for devising

the means to meet all the requirements– Description of the components

– Construction

– Testing

• If purchasing a system: – Design phase determines how to adapt the existing

software

– Construction: actual changes in program code



Design (continued)

• Symbols are used to communicate ideas about data, processes, and information– Visual information can be grasped more quickly

• Data flow diagram (DFD): describes the flow of data in a business operation using four symbols– External entities: individuals and groups external

to the system (customers, employees, etc.)

– Processes: an event or events that affect data

– Data store: any form of data at rest

– Direction of data flow: indicates how data moves



Design (continued)

• The simplicity of a DFD is its advantage• DFD symbols are suitable for describing any IS,

including noncomputer-based ISs• Can help pinpoint weaknesses:

– Where processes can be automated

– What is shared by different processes

– What can be changed to strengthen the IS

• A DFD cannot describe a system completely– Does not depict computations within processes or

timing relationships among data flows



Design (continued)

• Unified modeling language (UML): de facto standard for visualizing, specifying, and documenting software

• Helps developers communicate and logically validate desired features

• Is independent of programming languages• Provides standard symbols and notations for

depicting object-oriented elements

Design (continued)

• UML consists of diagrams:– Use case: an activity of the system in response to

the user (an actor)– Class: describes class structure and contents– Interaction: describes interactions of objects and

the sequence of their activities– State charts: indicate the states through which

objects pass and their responses to stimuli– Activity: represents highly active states triggered

by completion of other actions– Physical diagrams: high-level descriptions of

software modules




Design (continued)• Construction

– Consists of mostly programming activities

– May take months or years

– Completed modules are tested via a walk-through of the program logic or a simulation of actual program execution

• System testing– Tests the entire integrated system, comparing

results to the system requirements

• Testing period often is the victim of schedule or budget compression, resulting in poor testing


Implementation

• Implementation: delivery of a new system– Consists of two steps:

• Conversion• Training

– Training may or may not precede conversion

• Conversion: switching from the old system to the new system– Can be a very difficult time

Implementation (continued)• Four basic conversion strategies:

– Parallel conversion: the old system is used simultaneously with the new system at first

– Phased conversion: breaks the new IS into modules and integrates one at a time

• Reduces risk but delays some benefits

– Cut-over conversion (or flash cut conversion): immediately replaces all modules

• Risky but may be inexpensive

– Pilot conversion: introduces the IS into one business unit at a time

• Beta site: a site that tests the new system




Support• Support: begins after delivery, and includes two

responsibilities– Maintenance: postimplementation debugging,

updates, and adding postponed features

– User help

• Maintenance comprises up to 80% of IS budgets

• Support is the longest phase of the system life cycle

• Effective maintenance requires good system documentation


Agile Methods

• Agile methods: alternative development methods– Treat software development as series of contacts

with users

– Goal: fast development of software

– Improve software after user requests for modifications received

• Agile methods use iterative programming


Agile Methods (continued)

• Popular agile methods include:– Extreme programming (XP)

– Adaptive software development (ASD)

– Lean development (LD)

– Rational unified process (RUP)

– Feature driven development (FDD)

– Dynamic systems development method (DSDM)

– Scrum

– Crystal




• Major advantage of agile methods: – Fast development of application software

• Agile method risks include:– Analysis phase is limited or eliminated, increasing

the risk of incompatibilities

– More emphasis on programming, resulting in less documentation, which may make it difficult or impossible to make later modifications


• Manifesto for Agile Software Development expresses these priorities: – Individuals and interactions over processes

– Working software over comprehensive documentation

– Customer collaboration over contract negotiation

– Responding to change over following a plan

• Agile methods aim to have light but sufficient development processes




• User involvement is encouraged throughout the process

• Modules are tested immediately after completion• Communication with users is informal• Extreme programming uses two programmers

per module working on the same computer– Fosters constructive criticism and feedback

• Domino’s Pizza successfully implemented XP method; DaimlerChrysler did not


When to Use Agile Methods

• Agile methods are best used:– When a desired system is small

• Analysis is less important• Requires a smaller investment of resources

– For unstructured problems

– For developing user interfaces

– When users cannot specify all requirements at the start of the project

• They may be unfamiliar with the technology• Requirements may be difficult to conceptualize


When Not to Use Agile Methods

• Do not use agile methods when:– The desired system is large or complex

• System failure entails great financial loss

– The desired system must interface with other systems

• SDLC recommended for complex systems• Documentation is key for integration


Project Planning and Management Tools

• Several tools exist to help plan and manage a development project, including IS projects

• IBM’s Rational Portfolio Manager:– Helps plan investment in a new system and

manage the development project and delivery

• Primavera’s ProSight:– Helps plan and manage application portfolios,

resources, budgets, and compliance with government regulations


Project Planning and Management Tools (continued)

• Primavera’s eProject:– Web-based tool that allows members and

customers to define tasks and manage projects



Systems Integration

• Systems integration:– Examines the needs of entire organization– Produces a plan to combine disparate systems to

allow data to flow between units

• Some service companies specialize in systems integration

• Integration is more challenging than development• Legacy systems may need to be interfaced with

new systems



Systems Integration (continued)

• Systems integrators must be skilled in hardware and software

• May be difficult to overcome hardware and software incompatibility issues between systems

• Systems integration may span several organizations, requiring integration using telecommunications


Summary

• IT planning is important because of high investment costs and high risk in implementing enterprise applications

• Standardization is an important part of IT planning• Systems development life cycle (SDLC) has well-

defined phases: analysis, design, implementation, and support

• Purpose of systems analysis is to determine what needs the system will satisfy


Summary (continued)

• Feasibility studies determine if a proposed system is possible and desirable

• System requirements detail the features needed• Developers outline system components

graphically using tools like UML• Unified Modeling Language (UML) is used to

create model of desired system• Implementation includes training and conversion

from the old system to the new system


Summary (continued)

• Support entails maintenance and satisfying changing needs

• Agile methods are a popular alternative to traditional systems development life cycle

• Tools help plan and manage development projects

• Systems integration may be more complicated than systems development

• Great responsibility of IS professionals results in the desirability of certification

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Chapter 12: Systems Planning and Development

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