System Analysis and Design

preparation for the long quiz 2 in SISBUSI

Systems

• organized set of related components

• collection of subsystems that are interrelated and interdependent, working together to accomplish predetermined goals and objectives.

• EX:

  • Computer systme

  • Human body

System Analysis

process of studying an existing system to determine how it works and how it meets client and user needs

Clients

contract to have the systems analysis done

Users

people who will have contact with the system

employees and customers

System Design

process of developing a plan for an improved system

System Analyst

• performers both analysis and design

• sometimes a programmer is also involved in the analysis

• person who systematically assess how business function by examining the inputting and processing of data and the outputting of information with the intent of improving organizational processes.

• Key person in the SDLC

  • who analyzes the business situation, identifies opportunities for improvements, and designs an information system that adds value to the organizations to implement the improvements

Change

• must be an impetus for change

• related authority for change before an analysis and design project is under taken

Change Agent

system analyst is a catalyst to overcome the natural reluctance to change within an organization

Coordination

Communication

Planning and Design

A system analyst has 3 principal functions

Coordination

an analyst must coordinate schedules and system-related tasks with a number of people.

Communication

The analyst may need to make oral presentations and write reports for clients, users, and others involved with the system.

Planning and Design

• The systems analyst, along with the client organization, plans and designs the new system.

• This includes all the activities from beginning of the project until its final implementation

analytical mind

self-discipline

self-direction

ability to work without tangible results

Qualities of a System Analyst

Preliminary investigation

System Analysis

System Design

System Development

Implementation

System Development Life Cycle (SDLC) has 5 distinct phases

Preliminary Investigation

• 1st phase in the SDLC

The goal of this phase is to determine the problem and is sometimes called the feasibility study or system survey.

Tools of Preliminary Investigation

• system analyst will develop an organizational chart

• determine whether to proceed with the project

Nature of the Problem

The systems analyst and the users must agree on the (answer)

Scope of the problem

Determining the (answer) sets limitations on the eventual budget and schedules of the project.

Objectives

Determining the (answer) means to express what the user thinks the system should be able to do.

System Analysis

• 2nd phase in the SDLC

• systems analyst must:

  • Gather data

  • Analyze data

  • Determine system requirements

  • Report to management

Gathering Data

• The thing that system analyst do

• The systems analyst relies on the following sources when (answer):

  • Written documents

  • Interviews

  • Questionnaires

  • Observations

  • Sampling

Written Documents

Gathering documents includes procedures manuals, forms, and any kind of material that might have bearing on the problems in the organization.

Interviews

• Structured include only preplanned questions.

• Unstructured allow the systems analyst to digress from the formal line of questioning.

questionnaires

ideal for gathering information from a group too large to interview.

Observation

• Systems analysts must observe the flow of information in and out of an organization.

• Sometimes this requires them to be a temporary participant in the organization

Sampling

collection of data about quantities, costs, time periods, and other factors relevant to the system.

Analyze Data

• the thing that system analyst do

• The systems analyst uses charts and diagrams

  • Data flow diagrams

  • Decision Tables

Data flow Diagrams

• use in Analyzing data

• serve as a map of how data flows in and out of an organization and reveal procedures used.

Decision Tables

• use in analyzing data

• represents the logical decisions that must be made regarding potential conditions in a given system.

System Requirements

• in the system analysis phase

• a list of the things the system must be able to do

• This list of (answer) will determine the design of the new system

Report Management

• part of System Analysis

• Problems identified in the current system

  Requirements for the new system

  Cost analysis

  Recommendations for future action

System Design

• 3rd phase of the SDLC

• the phase in which the systems analyst actually plans the new system

Preliminary Design

• one of the two sub-phases of the system design

• systems analyst will review system requirements and consider whether the system should be:

  • centralized or decentralized

  • networked or not

  • run with purchased or custom software

  • outsourced or in-house

Prototyping

A (answer) of the new system is a limited working system that is developed quickly to produce output that looks like the output the finalized system will produce.

Detail Design

• one of the two sub-phases of system design

• systems analyst must now develop (answer) specifications, such as:

  • Output requirements

  • Input requirements

  • Files and databases

  • Systems processing

  • Systems controls and backups

Output requirements

• part of the detail design specifications

• systems analyst must determine:

  • what the client wants the system to produce.

  • the medium of the output.

  • the type of reports needed.

  • the contents of the output.

  • what forms will be used.

input requirements

• part of the detail design specifications

• The systems analyst must determine what (answer) to give the desired output.

Files and Database

• part of the detail design specifications

• The systems analyst will determine whether the files should be stored sequentially, directly, or by some other method.

• File storage must also be coordinated with the databases used by the client.

System Processing

• part of the detail design specification

• involves generating a diagram of how the flow of data works in the new system.

System Controls and backup

• part of the detail design specification

• designed to prevent fraud and tampering.

• system files should be (part of the answer) (copied) and the copies stored in a safe manner and location.

System Development

• 4th phase of the SDLC distinct phrases

• the system is actually developed and includes:

  • Scheduling

  • Programming

  • Testing

Scheduling

• part of the system development phase

• (answer) deadlines and milestones is another task of the systems analyst.

• (answer) involves determining the allocation of people and resources, monitoring schedules, and producing status reports.

Programming

• part of the system development phase

• At this point in systems development, programmers are given program design specifications and they begin to write code.

Testing

• part of the system development phase

• After the program for the new system has been written, it must be (answer) under a variety of conditions.

Implementation

• 5th or last phase of the SDLC

• for (answer) to be successful, the ff activities are required:

  • •Training

    • Equipment conversion

    • File conversion

    • System conversion

    • Auditing

    • Evaluation

    • Maintenance

Training

• activities in the implementation phase

• A system will only be as good as the people who use it. Therefore, (answer) the users is very important.

Equipment Conversion

• activities in the implementation phase

• Implementing a system requires that consideration has been given to how best to convert to the new system.

• Issues of availability of space, accessibility, and cleanliness of the work area cannot be overlooked.

File Conversion

• activities in the implementation phase

• Converting old file structures to that needed by the new system can take a long time.

• Care must be taken to not corrupt old files, lose files, or disrupt normal operations of the client organization during this conversion.

System Conversion

• activities in the implementation phase

• A systems analyst will need to determine in what way the client organization should convert to the old system.

Auditing

• activities in the implementation phase

• To guard against deliberate or unintentional violations in security, the systems analyst designs an (answer) trail.

Evaluation

• activities in the implementation phase

• (answer) is needed to determine if the system is:

  • working

  • meeting the organizational requirements

  • meeting the original budget limitations

Maintenance

• activities in the implementation phase

• is an ongoing activity and includes monitoring and making revisions throughout the life cycle of the system.

System Analysis and Design

• As performed by system analysts, seeks to analyze data input or data flow systematically, processing or transforming data, data storage, information output within the context of a particular business

• Is used to analyze, design and implement improvements in the functioning of businesses that can be accomplished through the used of computerized info. systems.

• Lends structure to the (answer)

Consultant

• roles of the system analyst

• May be hired to address information systems issues within a business

• Outside (answer) can bring the companies a fresh perspective that other members of an organization do not possess

Support Expert

• roles of the system analyst

• Draws on professional expertise concerning computer hardware and software and their uses in the business

• you are not managing the project, you are merely serving as a resource for those who are.

Agent of Change

• roles of the system analyst

• defined as a person who serves as a catalyst for change, develops a plan for change, and works with others in facilitating that change

Quliaties of the system analysis

• Problem Solver

• Systematically tackle the situation at hand through skillful application

• Communicator

• have computer experience to program

• possess strong personal and professional ethics

• self-discipline and self-motivated

System Development Life Cycle

• Is the process of understanding how an information system (IS) can support business needs, designing the system, building it, and delivering it to users.

Business Analyst

• System Analysis Specialization

• Analyzing the key business aspects of the system

  -Identifying how the system will provide business value

  -Designing the new business processes and policies

System Analyst

• system analyst specialization

• -Identifying new technology can improve business processes

  -Designing the new business processes

  -Designing the information system

  -Ensuring the system conforms to information system standards

Infrastructure Analyst

• system analyst specialization

• -Ensuring the system conforms to infrastructure standards

  -Identifying infrastructure changes needed to support the system

Change Management Analyst

• system analyst specialization

• -Developing and executing a change management plan

  -Developing and executing a user training plan

Project Manager

• System Analysis Specialization

• -Managing the team of analysts, programmer, technical writers and other specialists

  -Developing and monitoring the project plan

  -Assigning resources

  -Serving as the primary point of contact for the project.

Application Portfolio

prioritized list of both existing and potential IT applications of a company.

Information System Planning Process

Organizational strategic Plan

• part of the Information System Planning Process

• it’s in the image, which is the 2nd stage

• one of the inputs in developing the IT strategic plan

• states the firm’s overall mission, the goals that follow from that mission, and the broad steps necessary to reach these goals.

IT architecture

• part of the information system planning process

• called “current (answer)” in the chart

• one of the inputs in developing the IT strategic plan

• delineates the way an organization’s information resources should be used to accomplish its mission.

IT Strategic Plan

• part of the information system planning process

• a set of long-range goals that

• describe the IT infrastructure and major IT initiatives needed to achieve the goals of the organization.

IT Steering Committee

comprised of managers and staff representing various organizational units, establishes IT priorities and ensures that the MIS function meets the needs of the enterprise.

IS Operational Plan

• part of the information system planning process

• a clear set of projects that the IT department and functional area managers will execute in support of the IT strategic plan

• Elements:

  • Mission

  • IT environment

  • Objectives of the IT function

  • Constraints of the IT function

  • Application portfolio

  • Resource allocation and project management

Traditional System Development Life Cycle

Software Development Life Cycle

• another SDLC

• the traditional systems development method that organizations use for large-scale IT projects.

• SDLC processes are systems investigation, systems analysis, systems design, programming, testing, implementation, operation and maintenance.

Waterfall Approach

• when tasks in one phase are completed before the work proceeds to the next stage.

• the image of the traditional system development life cycle looks like this

System Investigation

System Analysis

System Design

Programming

Testing

Implementation

Operation

Maintenance

Traditional System Development Life Cycle steps

SDLC - System Investigation

• Begins with the business problem (or opportunity) followed by the feasibility analysis.

• Feasibility study

• Go/No-Go Decision

Feasibility Study

• main task of the Systems Investigation phase.

• it helps the organization choose between 3 options:

  • (1) Do nothing and continue to use the existing system unchanged.

  • (2) Modify or enhance the existing system.

  • (3) Develop a new system.

SDLC System Analysis

• Is the examination of the business problem that the organization plans to solve with an information system.

• Main purpose is to gather information about existing system to determine requirements for the new or improved system.

• Deliverable is a set of system requirements.

SDLC System Design

• Describes how the system will accomplish this task.

• Deliverable is the  technical design that specifies:

  • System outputs, inputs, user interfaces.

  • Hardware, software, databases, telecommunications, personnel & procedures.

  • Blueprint of how these components are integrated.

SDLC Programming

involves the translation of a system’s design specification into computer code.

SDLC Testing

• checks to see if the computer  code will produce the expected and desired results under certain conditions.

• designed to delete errors (bugs) in the computer code. These errors are of two types:

  • Syntax errors ( e.g., misspelled word or a  misplaced comma)

  • Logic errors that permit the program to run but result in incorrect output.

SDLC Implementation

• or deployment is the process of  converting from the old system to the new system

• 4 major conversion strategies ;

  • Direct Conversion - old system is cut-off and the new system turned on

  • Pilot Conversion - that introduces the new system in one part of the organization on a trial basis

  • Phased Conversion - introduces components of the new system in stages, until the entire new system is operational.

  • Parallel Conversion - old system and the new system operate simultaneously for a period of time

SDLC Operation and Maintenance

• assess the system’s capabilities and to determine if it is being used correctly.

• Types of (answer)

  • Debugging: A process that continues throughout the life of the system.

    Updating: Updating the system to accommodate changes in business conditions.

    (answer): That adds new functionally to the system –adding new features to the existing  system without disturbing its operation.

Joint Application Design

•  A group-based tool for collecting user requirements and creating system designs.

Computer Assisted Software Engineering

• CASE

• is a development approach that uses specialized tools to automate many of the tasks in the SDLC; upper CASE tools in SDLC automate the early stages of  the SDLC, and lower case tools automate the later stages.

Integrated computed assisted software engineering tools

• ICASE

• CASE tools that provide links between upper CASE and lower CASE tools

Rapid Application Development

development method that uses special tools and an iterative approach to rapidly produce a high-quality system.

Agile Development

Development method that delivers functionality in rapid iterations requiring frequent communication, development, testing, and delivery.

End User Development

development method that has the actually user develop their own application(s) for use.

Component Based Development

that uses standard components to build applications.

RAD vs SDLC

Outsourcing

when an organization acquires IT applications or services from outside contractors or external organizations

Application Service Provider

is an agent or vendor who assembles the software needed by enterprises and packages the software with services such as development, operations and maintenance.