Chapter 14 - Information Systems Development

What is the System Development Life Cycle?

What is an information system (IS)?

° A set of hardware, software, data, people, and procedures that work together to produce information

° Supports daily, short-term, and long-range activities of users

What is the system development life cycle (SDLC)?

° A set of activities developers use to build an information system

° Used to guide system developers

• Through development of systems

• To maintain and monitor ongoing activities

° Sometimes referred to as software engineering

What are the phases in the SDLC?

What are guidelines for system development?

° Group activities or tasks into phases

• Number of phases can vary

• Terminology can vary

° Involve the users

• Anyone for whom the
system is being built

° Develop standards

• Sets of rules and
procedures a company
expects employees to
accept and follow

• Helps people working on the same project produce consistent results

Who participates in the system development life cycle?

° Should involve representatives from each department in which the proposed system will be used

What is a systems analyst?

° The users’ primary contact person

° Responsible for designing and developing an information system

° Liaison between the users and the IT professionals

° Converts user requests into technical specifications

What is the project team?

° A team formed to work on a project from beginning to end

° Consists of users, the systems analyst, and other IT professionals

What is project management?

° The process of planning, scheduling, and then controlling the activities during the SDLC

° Goal is to deliver an acceptable system to the user in an agreed-upon time frame, while maintaining costs

° Must identify and record items for the project plan

What is a Gantt chart?

° A popular tool used to plan and schedule the time relationships among project activities

° Developed by Henry L. Gantt

° A bar chart that uses horizontal bars to show project phases or activities

What is project management software?

° Assists in planning, scheduling, and controlling development
projects

What is feasibility?

° A measure of how suitable the development of a system will be to the company

° Must frequently be re-evaluated during the SDLC

° Four tests to evaluate feasibility of a project

What is documentation?

° The collection and summarization of data and information

° Includes reports, diagrams, programs, or any other deliverable generated during the SDLC

What are six data and information gathering techniques?

° Project team members gather data and information

What is a joint-application design (JAD) session?

° A lengthy, structured, group work meeting where users and IT professionals discuss an aspect of the project

° Goal is to
obtain group
agreement
on an issue

What are some research sources?

° Newspapers, computer magazines, reference books, and the Web

Company on the Cutting Edge

Ziff Davis Media

° The leading information authority for buying, using, and experiencing technology and the Internet

° Largest technology and Internet magazine publisher in the United States

° Publishes many industry-leading consumer and business publications

What Initiates the System Development Life Cycle?

What are some reasons to create or modify an information system?

What is an informal project request?

° A user may request a new or modified information system verbally in a telephone conversation or written as an e-mail message

What is a request for system services?

° Also called a project request

° Users write a formal request for a new or modified information system

° The document becomes the first item in the project notebook

Case Study – Web Lane Café

° The Web Lane Cave is a cybercafé, a coffee house or restaurant that provides Web access to its customers

° It is a worldwide chain of cybercafés with locations in 40 cities around the world

° Staff members can provide assistance; training courses provided for beginning computer users

° Cafes use the latest hardware and software

° It provides 30 minutes free computer/Web access with each beverage or snack purchased; additional time can be purchased for $5.00 per hour

Case Study – Web Lane Café

° Started operations in 1995 and now serves thousands of customers

° The Web site has hundreds of hits a day

Case Study – Web Lane Café

° CEO John Simmons

° Computers and equipment are provided without charge by vendors to showcase their products; customers directed to vendor’s online storefront for purchases

° Vendors request information from Carla Rosatti, the marketing manager; the number of requests is rising quickly

° Carla would like to add the vendor information to the Web to save time and money

Case Study – Web Lane Café

° Carla sends an e-mail message to the vice president of information systems

Case Study – Web Lane Café

° He agrees and tells her to fill out a Request for System Services form and submit it to Mohammed Hossain, chair of the steering committee

Planning Phase

What is the planning phase?

° Begins when the steering committee receives a project request

° Four major activities are performed

• Review and approve the project requests

• Prioritize the project requests

• Allocate resources such as money, people, and equipment to approved projects

• Form a project development team for each approved project

Case Study – Planning at Web Lane Cafe

° Mohammed Hossain distributes the project request to all members of the steering committee

° Carla Rosatti is invited to the steering committee meeting to discuss the project request

° The steering committee decides the project request identifies an improvement; potential for considerable savings for the company with benefits for vendors

° The request is approved

° Tyrone Greene, vice president of information systems, assembles a system development team

° Sadie Lapinski, senior systems analyst, assigned as project leader

Analysis Phase

What is the analysis phase?

° Consists of two major tasks

What is the preliminary investigation?

° Sometimes called the feasibility study

° To decide whether the problem or improvement in a project request is worth pursuing

° The system analyst conducts a very general study of the project

What is a feasibility report?

° Also sometimes known as the feasibility study

° A report used to present the findings of the preliminary investigation

° Contains five major sections

• Introduction

• Existing system

• Benefits of a new system

• Feasibility of a new system

• Recommendation

Case Study – Analysis: Preliminary Investigation at Web Lane Cafe

° Sadie Lapinski, senior systems analyst, meets with Carla Rosatti to discuss the project

° Sadie interviews the controller, Mohammed Hossain, to obtain some general cost and benefit figures

° She calls a vendor

° She prepares the feasibility report

° The team members review the report and Sadie submits it to the steering committee

° The report recommends continuing into the detailed analysis phase

° The steering committee agrees

What is a detailed analysis?

° Sometimes called logical design

° Involves three major activities

° The proposed solution is developed without regard to any specific hardware or software

What is structured analysis and design?

° A technique that attempts to address a problem by using graphics and other tools

° Used to document findings in a way than can be understood by everyone

Technology Trailblazer

Ed Yourdon

° Recognized as one of the 10 Influential Men and Women of Software

° Noted for developing the method of object-oriented systems analysis and design

° Author of more than two-dozen computer books and 200 technical articles

° Publishes a weekly
e-zine, The Yourdon Report, and an informative Web site

What is an entity-relationship diagram (ERD)?

° Also called an E-R diagram

° A tool that
graphically
shows the
connections
between
entities in a
system

What is a data flow diagram (DFD)?

° A tool that graphically shows the flow of data in a system

What is a context diagram?

° A DFD that identifies only the major processes

• DFDs are prepared on a level-by-level basis

• Lower level
DFDs add
detail and
definition to
the higher
levels

What is a project dictionary?

° Sometimes called the repository

° Contains all the documentation and deliverables of a project

° Helps keep track of the huge amount of details in a system

° One section explains every item found on the diagrams

° A variety of techniques used to enter items in a project dictionary

What is structured English?

° A style of writing that describes the steps in a process

° Used to explain details of a process in the project dictionary

What is a decision table?

° A table that lists a variety of conditions and the actions that correspond to each condition

° Used when a process consists of many conditions or rules

What is a decision tree?

° A diagram that shows conditions and the actions graphically

° Used when
a process
consists of
many
conditions
or rules

What is a data dictionary?

° Each data item has an entry in the data dictionary

° Stores the data item’s name, description, and other details about each data item

What is the system proposal?

° Used to assess the feasibility of each alternative solution

° Recommends the most feasible solution for the project

° Systems analyst presents the system proposal to the steering committee for approval

° If approved, the project enters the design phase

What is packaged software?

° Sometimes called commercial off-the-shelf software

° Pre-written software available for purchase

° Available for different types of computers

° Two types of packaged software

How can you locate software vendors?

° Search for names and vendors on the Web by entering your requirement as the search criteria

° Read computer magazines and trade publications

• A magazine written for a specific business or industry

What is custom software?

° Application software developed by the user or at the user’s request

° Used when a company cannot find a package that meets all its needs

° Matches the company’s requirements exactly

° Usually more expensive and takes longer to design and implement than packaged software

Case Study – Detailed Analysis at Web Lane Cafe

° Team gathers data and information by interviewing employees and vendors and observing marketing staff

° Team prepares documents to record their findings

° Documents become part of the project notebook

° After two months of study, Sadie discusses findings with supervisor, Tyrone Greene

° Sadie recommends their Web site include a link to Vendor Information

° Tyrone writes a system proposal for the steering committee to review

° Tyrone recommends that Jesse Martinez, Webmaster, modify the Web site in house

° Also recommends that the Web Lane Café invest in a larger database server

° The steering committee agrees and the design phase begins

Design Phase

What is the design phase?

° Consists of two major activities

• If necessary, acquire hardware and software

• Develop all of the details of the new or modified information system

° Systems analyst often performs these two activities at the same time

What is needed to acquire new hardware and software?

° Identify all the hardware and software requirements of the new or modified system

° Summarize the requirements for potential vendors

What is an e-zine?

° An electronic magazine

° A publication available on the Web

° By using
the Web,
the systems
analyst can
locate
information
more quickly
and easily
than in the
past

What are three basic documents used to summarize technical specifications?

° Documents are used to summarize requirements for vendors

What is an online product catalog?

° A catalog on the Web that provides up-to-date and easy access to products, prices, specifications, and ordering information

° One way to locate vendors

What is a value-added reseller (VAR)?

° A company that purchases products from manufacturers and then resells these products to the public

° Offers additional services with the product

• User support, equipment maintenance, training, installation, warranties

° Most manufacturers have requirements that the VAR must meet

What is a turnkey solution?

° A complete system provided by a VAR

° Advantage of a full-service VAR is you deal with only one company for an entire system

What is involved in testing and evaluating vendor proposals?

° Vendors respond to RFQs and RFPs with completed quotations and proposals

° System analysts evaluate the proposals and select the best one

° After rating the proposals, the systems analyst presents a recommendation
to the steering committee

Where can you find a demonstration copy?

° Vendors may provide a copy

° Some vendors allow you to download or run a demonstration copy directly from their Web site

What is an end-user license agreement (EULA)?

° Gives you the legal right to use software under certain terms and conditions

° When you purchase software, you do not own it

° Most license agreements include restrictions

• Software used on one computer by one user

• Restrictions on copying the software, modifying it, or translating it to another language

Case Study – Design: Hardware Acquisition at Web Lane Cafe

° Sadie and her team compile a requirements list for the database server

° They prepare an RFP and submit it to 12 vendors

° They get 10 replies

° Development team selects 2 to evaluate

° Team members research the two servers, and select the best one

° Sadie summarizes findings in a report to the steering committee

° Committee gives authorization to award a contract

° Sadie informs all 12 vendors of the decision

What is detailed design?

° Sometimes called physical design

° Develop detailed design specifications for the components in the proposed
solution

° Specifies
hardware and software for automated procedures

What is database design?

° The system analyst builds upon the data dictionary developed during the analysis phase

° Should represent accurately the data requirements of the company

° Identifies those data elements that currently exist within the company and those that are new

What is input and output design?

° The systems analyst carefully designs every menu, screen, and report specified in the requirements

° Outputs usually are designed first because they help define the requirements for the inputs

° A mockup
is a sample
of the
input or
output that
contains
actual data

What is a layout chart?

° Designed after the mockup is approved by users

° More technical

° Contains programming-like notations for the data items

What is program design?

° Systems analyst identifies the processing requirements, or the logic, for each program in the system

° Prepares the program specification package which communicates program requirements clearly to the programmer

What is a systems flowchart?

° Documents relationships among programs in a process

° Shows how other elements of the system interact with a major process

What is a prototype?

° A working model of the proposed system

° Systems analyst actually builds a functional form of the solution during design

° Users work with the system to make sure it meets their needs

° Once users approve a prototype, system developers implement a solution

° The systems analyst often can convert the working model to the actual solution

What is computer-aided software engineering (CASE)?

° Software tools designed to support one or more activities of the SDLC

° Used to increase the efficiency and productivity of the product development team

What is an integrated CASE product?

° Some CASE tools exist separately

° Others are integrated

• Called
I-CASE or a CASE workbench

Company on the Cutting Edge

Visible Systems Corporation

° Developer of Visible Systems Corporation's Visible Advantage™, an enterprise architecture and data warehouse development CASE tool

° Another product is Visible Analyst^®, an
I-CASE tool that provides graphical analysis and design resources for applications and database designs

Design Phase

What are quality review techniques?

° A structured walkthrough, a step-by-step review of any SDLC deliverable

° Used to review the detailed design specifications before they are given to the programming team

° Review process should include users, the senior systems analyst, and members of the project team

Case Study – Detailed Design at Web Lane Cafe

° Sadie and her team begin designing the Vendor Web System

° They study current vendor information and conduct more interviews

° They make changes to the company’s database, Web site, and the associated programs

° They prepare documents

° They meet with users and IT personnel to walk through the deliverables

° They locate and correct errors

° They present the design to the steering committee

° Committee agrees with the design solution and consents to implement it

Implementation Phase

What is the implementation phase?

° Purpose is to construct, or build, the new or modified system and then deliver it to the users

What is the program development life cycle (PDLC)?

° Programmers write programs from the program specification package created during analysis

° Follow an organized set of activities known as the PDLC

° Six steps

What are the three types of tests performed by system developers?

What is training?

° Involves showing users exactly how they will use the new hardware and software in the system

° Could be one-on-one sessions or classroom-style lectures

° Users should practice on the actual system during training

° Users
should
receive
user
manuals
for
reference

What are conversion strategies?

° Strategies used to change from the old system to the new system

What is direct conversion?

° The user stops using the old system and begins using the new system on a certain date

° Also called an abrupt cutover

What is parallel conversion?

° Consists of running the old system alongside the new system for a specified time period

°