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									ITEC 2010 “Systems Analysis and Design, I”
            LECTURE 8-1:
  Evaluating Alternatives for Requirements,
   Environments, and Implementation




                [Prof. Peter Khaiter]         1
Topics

   Project Management Perspective
   Scope and Level of Automation
   Selecting Alternatives
   Range of Application Types
   Deployment Environment
   Implementation Alternatives
   Contracting with Vendors
   RFP Table
   Choosing a Vendor
   Presenting Results and Making Decisions
                                          2
Project Management Perspective

   Nine areas of project management


        Scope                Procurement
        Time                 Communications
        Cost                 Risk
        Quality              Integration
        Human resources
                                                3
Deciding on Scope and Level of
Automation
   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
 To avoid this problem we need to formalize the process of
   selecting which functions are critical and which are not
• A common approach is to list requested functions and
   categories them in terms of “mandatory”, “important” and
   “desirable”. This information is presented in scoping table
• Scoping table is a tabular list of all the functions to be
   included within a system (an expanded version of the event
   table)                                                      4
Determining the Level of
Automation
   Level of automation is a description of the kind
    of support the system will provide for each
    function
   For each function at least three levels can be
    defined: low, middle, and high
   Low level
      Functions automated for simple computer record keeping
   Medium level
      Midrange point that combines features from low and high
      alternatives (usually it is a compromise of what is necessary
      and what is justified at the current stage of technology and
      budget)
   High level
      System automates most processing of business functions
      (High-end automation often involves creating new processes
      and procedures)
                                                                 5
Features of Low Level
   computer system only provides simple record
    keeping
   data input screens capture information and insert
    it into a database
   simple types of field edits and validations on
    input data are included
   the system date may be used for the order date
   line items for the order are entered manually
   the system may or may not automatically
    calculate the price
   usually stock on hand are not verified
   at the end of entering the order, the information
    is stored in the database
                                                    6
Scoping List of Potential Functions
for RMO




                                      7
Selecting Alternatives
   Entire group of alternatives is evaluated together
    to provide “big picture” view of proposed system

   Key criteria that are used
      Strategic plan

      Economic feasibility

      Schedule and resource feasibility

      Technological feasibility

      Operational, organizational, and cultural feasibility

                                                              8
Preliminary Selection of
Alternative Functions for RMO




                                9
Defining the Application
Deployment Environment
   Configuration of
      Computer hardware
      System software
      Networks
      Development tools

   Existing environment generally considered
    and compared with proposed environment

                                            10
Range of Application Types

   Stand-alone applications on desktops or
    laptops, small servers and PDA devices

   Online interactive applications – wired
    & wireless

   Distributed applications across multiple
    platforms

   Internet-based applications
                                              11
Hardware, System Software, and
Networks
   Computers 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      12
Deployment Environment:
Characteristics to Consider
   Compatibility with system requirements

   Compatibility among hardware and system
    software

   Required interfaces to external systems

   Conformity with IT strategic plan and
    architecture plans

   Cost and schedule
                                              13
Just for Fun!




           http://www.visualjokes.com
                                        14
Development Tools

   Development environment – programming
    languages, CASE tools, and other software
    used to develop application software
   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            15
Existing Processing Environment
at RMO




                                  16
Processing Environment
Alternatives




                         17
Strategic Directions for RMO
Processing Environment




                               18
Choosing Implementation
Alternatives
   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
                                                 19
Implementation Alternatives




                              20
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
                                                     21
Partial Matrix of General
Requirements




                            22
Partial Matrix of Functional
Requirements




                               23
Partial Matrix of Technical
Requirements




                              24
Making the Selection
   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      25
Contracting with Vendors
   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                              26
Sample RFP Table of Contents


I. Introduction and Background

II. Overview of Need

III. Description of Technical Requirements

IV. Description of Functional Requirements


                                             27
Sample RFP Table of Contents
(continued)‫‏‬


V.    Description of General Requirements

VI.   Requested Provider and Project Information

VII. Details for Submitting Proposal

VIII. Evaluation Criteria and Process


                                               28
Sample RFP
Table of
Contents ‫‏‬




             29
Benchmarking and Choosing a
Vendor
   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

                                                     30
Presenting Results and Making
Decisions

 Compile and organize documentation
 Present alternatives and critical
  issues in easy-to-understand but
  complete manner
 Final choice generally made by
  executive steering committee
 Format of documentation and
  presentation style varies with
  organization                      31
                Readings


Today’s lecture: Chapter 8 – “Evaluating
Alternatives for Requirements, Environments,
and Implementation”


For next lecture: Chapter 9 – “Elements of
Systems Design”



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