Chapter 8 - Systems Analysis and Design

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Systems Analysis – ITEC 3155
Evaluating Alternatives for Requirements,
Environment, and Implementation
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Learning Objectives
 Prioritize
the system requirements based on the
desired scope and level of automation for the
new system
 Describe
the strategic decisions that integrate the
application deployment environment and the
design approach for the new system
 Determine
alternative approaches for system
implementation
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Learning Objectives (continued)
 Evaluate
and select an implementation approach
based on the needs and resources of the
organization
 Describe
key elements of a request for proposal
(RFP) and evaluate vendors’ proposals for
outsourced alternatives
 Develop
a professional presentation of findings to
management
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Overview
 Chapter
explains last three activities of analysis

Prioritize systems requirements

Generate and evaluate alternatives

Review recommendation with management
 Refocus
project direction
 Transition
from discovery and analysis to
solutions and design
 Set
direction for design and implementation of
solution system
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Project Management Perspective
 Project
manager and senior technical members
of project team work together
 Eight
areas of project management

Scope

Human resources

Time

Procurement

Cost

Communications

Quality

Risk
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Deciding on Scope and Level of Automation
(pg. 290)
 Scope
determines which business functions will
be included in system
 Level
of automation is how much computer
support exists for functions included in scope
 Scope

creep
Requests for addition of system functions after
requirements have been defined and decision has
been made
 Users
typically request more business functions
than budget allows
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Determining the Level of Automation
 Low

level
Functions automated for simple computer record keeping
 Medium

Midrange point that combines features from low and high
alternatives
 High

level
level
System automates most processing of business functions
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RMO Customer Support System Functions, Priority, and
Three Levels of Automation (Partial Figure 8-1)
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Selecting Alternatives
 Entire
group of alternatives is evaluated together
to provide “big picture” view of proposed system
 Key
criteria that are used (pg. 294)

Strategic plan

Economic feasibility

Schedule and resource feasibility

Technological feasibility

Operational, organizational, and cultural feasibility
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Defining the Application
Deployment Environment
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(pg. 297)
 Configuration
of

Computer hardware

System software

Networks

Development tools
 Existing
environment generally considered and
compared with proposed environment
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Range of Application Types
 Stand-alone
applications on mini- and personal
computers
 Online
interactive applications
 Distributed
applications
 Web-based
applications
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Hardware, System Software, and
Networks
 Computers
8
range from handheld to super
computers
 Operating
systems range from Windows to Unix
 Database
management systems range from
Oracle to SQL Server to IBM DB2
 Software
components and standards range from
Java 2 Enterprise (J2EE) to Microsoft .NET
 Web
servers range from IIS to Apache
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Deployment Environment Characteristics
to Consider
 Compatibility
with system requirements
 Compatibility
among hardware and system
8
software
 Required
interfaces to external systems
 Conformity
with IT strategic plan and architecture
plans
 Cost
and schedule
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Development Tools
environment – programming
languages, CASE tools, and other software used
to develop application software
 Development
 Java
and Visual Studio .NET are examples
 Application
deployment environment decisions
limit development tool choices

Operating system environment

Database management system (DBMS)

Distributed software standard
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Choosing Implementation Alternatives
(pg. 303)
 Variations
on obtaining system

Facilities management – outsource all IS support

Packaged software, turnkey system, ERP system

Custom-built software systems

In-house development
 Selection
dimensions

Buy vs. build

In-house vs. outsource
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Selecting an Implementation Alternative
 Identifying
criteria for selection

Comparisons can be difficult

Different proposed systems have strengths in
different areas
 Three
major areas to consider

General requirements

Technical requirements

Functional requirements
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Partial Matrix of Technical Requirements,
Weights, and Scores for Alternatives (Figure 8-9)
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Making the Selection
(pg. 310)
 First,
rate each alternative with raw score
 Weighted
scores are then tabulated and
compared to make a choice
 RMO
decided on in-house development for most
CSS development to keep expertise within RMO
 RMO
wants to hire some new technical
specialists
 RMO
feasibility review showed no serious
problems – after specialists are added
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Contracting with Vendors
(pg. 311)
 Generate
request for proposal (RFP)

Formal document sent to vendors if in-house
development is not selected

States requirements and solicits proposed
solutions

Considered a competitive contract offer

Bid on supplying hardware, software, and/or
support services
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Benchmarking and Choosing a Vendor
(pg. 312)
 Observe
in use or install trial version
 Benchmark
– evaluate the system against a
standard
 Visit
another company using a particular system
 Develop
a contract

Fixed-dollar – risk is on vendor

Cost-plus-percentage – risk is on purchaser

Cost-plus-fixed-fee – risk is shared by both
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Presenting Results and Making Decisions
(pg. 313)
 Compile
and organize documentation
 Present
alternatives and critical issues in easy-tounderstand but complete manner
 Final
choice generally made by executive
steering committee
 Format
of documentation and presentation style
varies with organization
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Summary
 These
activities are primarily project manager
responsibilities with support from project team
 Focus
of project changes from discovering
requirements to developing solution system
 Prioritize
requirements based on scope and level
of automation

Scope of new system determines functions it will
support

Level of automation is a measure of how
automated the selected functions will be
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Summary (continued)
 Application
deployment environment

Computer hardware, systems software, and
networks in which new system will operate

Determines constraints imposed on system
development alternatives
 Analyst
must define environment to match

Application requirements

Organization’s strategic application plans

Organization’s technology architecture plans
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Summary (continued)
 Determine
what alternatives are possible for
developing solution
 Implementation
alternatives include

Building system in-house

Buying packaged or turnkey solution

Contracting with developer to build system
(outsource)
 Develop
recommendations and present to
management to make funding decisions
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