Systems analysis & design CH. 1

Information Technology Departments

-Application development -systems support and security -user support -database administration -network administration -web support -quality assurance (QA)

Agile Methods

-Are the newest development -Emphasizes continuous feedback -Iterative development -Spiral model -process determines the end result -Other adaptive variations and related methods exist -Two examples are Scrum and Extreme Programming (XP) -Analysts should understand the pros and cons of any approach before selecting a development method

E-commerce includes two main sectors

-B2C (business-to-consumer) -B2B (business-to-business)

Modeling

-Business model -Requirements model -Data model -Object model -Network model -Process model

Knowledge management systems

-Called expert systems -Simulate human reasoning by combining a knowledge base and inference rules -Many knowledge management systems use a technique called fuzzy logic

Computer-Aided Systems Engineering (CASE) Tools

-Can generate program code, which speeds the implementation process

Object-oriented Analysis

-Combines data & processes that act on the data into things called ___________ -is a member of a class -possess characteristics called properties -Methods changes it's properties -A message requests specific behavior or information from another _______ -Usually follow a series of analysis and design phases that are similar to the SDLC -Interactive model

Processes

-Describe the tasks and business functions that users, managers, and IT staff members perform to achieve specific results

Software

-Horizontal system -Vertical system -Legacy systems

They Systems Analyst Position Certifiation

-Important credential

Transaction processing systems

-Involve large amounts of data and are mission-critical systems -Efficient because they process a set of transaction-related commands as a group rather than individually

Career Opportunities

-Job titles -Company organization -Company size -Corporate culture -Salary, location, and future growth

Other Development Methods

-Joint application development (JAD) -Rapid application development (RAD) -Might encounter other systems development techniques -Rational Unified Process (RUP®) -Microsoft Solutions Framework (MSF)

Information systems integration

-Most large companies require systems that combine transaction processing, business support, knowledge management, and user productivity features

In the past, IT managers divided systems into categories based on the user group the system served

-Office systems -Operational systems -Decision support systems -Executive information systems

New Kinds of Companies

-Production-oriented -Service-oriented -Internet-dependent -Dot-com (.com) -Brick-and-mortar

Business support systems

-Provide job-related information to users at all levels of a company -Management information systems (MIS) -Radio frequency identification (RFID) -What-if

They Systems Analyst Position Required Skills and Background

-Solid technical knowledge, strong oral and written communication skills and analytic ability, and an understanding of business operations and processes

Prototyping

-Speeds up the development process significantly -Important decisions might be made too early, before business or IT issues are thoroughly understood -Can be an extremely valuable tool

People

-Stakeholders -Users, or end users

Structured Analysis

-Systems development life cycle (SDLC) -Predictive approach -Uses a set of process models to describe a system graphically -Process-centered technique -Waterfall model -Deliverable or end product -Disadvantage in the built-in structure of the SDLC, because the waterfall model does not emphasize interactivity among the phases -This criticism can be valid if the SDLC phases are followed too rigidly -Adjacent phases usually interact

Data 2

-Tables store data -By linking the tables, the system can extract specific information

The systems Analyst Position Responsibilities

-Translate business requirements into IT projects

Disadvantages of agile methods

-weak documentation -blurred lines of accountability -little emphasis on company's bigger picture -long series of iterations can add to project cost and development time

business process

A description of specific events, tasks, and desired results.

scalable design

A system design that can expand to meet new business requirements and volumes

Object-oriented analysis

Combines data and the processes that act on the data into objects. the result is a set of software objects that represent actual people, things, transactions, and events.

database administration

Database design and management group responsible for defining and organizing the structure and content of the database, and maintaining the database.

data model

Describes data structures and design

object model

Describes objects, which combine data and processes.

network model

Describes the design and protocols of telecommunications links.

Business model or requirements model

Describes the information that a system must provide

EDI

Electronic Data Interchange

XML

Extensible Markup Language-is a flexible data description language that allows Web-based communications between different software and hardware environments.

technical support

Includes six main functions: application development, systems support and security, user support, database administration, network administration, and Web support.

network administration

Involves tasks such as (1) installing new computers and devices, (2) monitoring the network to ensure it's performing efficiently, (3) updating and installing new software on the network, and (4) configuring, or setting up, proper security for a network.

Systems Implementation

New system is constructed Programs are written and tested System is installed, completely functioning Deliverable is systems evaluation

methods

O-O design built in process that can change an objects properties. Ex: an ORDER object might have a property called STATUS that changes when a CUSTOMER object clicks to place, confirm, or cancel the order.

Supervisors (team leaders)

Oversee operational employees and carry out day-to-day functions

user support

Provides users with technical information, training, and productivity support

systems support and security

Provides vital protection and maintenance services for system hardware and software, including enterprise computing systems, networks, transaction processing systems, and corporate IT infrastructure

feasibility study

Reviews anticipated costs and benefits and recommends a course of action based on operational, technical, economic, and time factors.

interactive model

System model in which model planning, analysis, and design tasks interact continuously to produce prototypes that can be tested and implemented

Business Process Reengineering (BPR)

When companies attempt to simplify operations or reduce costs, a popular strategy is to have managers and systems analysts perform ____.

spiral model

a series of iterations or revisions, based on user feed-back.

fuzzy logic

allows inferences to be drawn from imprecise relationships. Values need not be black and white, like binary logic, but can be many shades of gray. the results will display in priority order.

Extreme Programming (XP)

an adaptive process that focuses on forceful interaction between developers and users to define and achieve project goals. Stresses certain key values, such as communication, simplicity, feedback, courage, and respect among team members.

class

an object is a member of a ______, which is a collection of similar objects. Objects possess characteristics called properties, which the object inherits from it's class or possesses on it's own. Ex: ______ called PERSON includes instructor & student, because the person ______ has a property called address

Knowledge Management systems

are called expert systems because they simulate human reasoning by combining a knowledge base and inference rules that determine how the knowledge is applied.

iterative development

can be traced back 20yrs to Japanese auto firms that were able to boost productivity by using a more flexible manufacturing system, where team based effort and short term milestones helped keep quality up and costs down.

Enterprise applications

company wide applications, such as order processing systems, payroll systems, and company communication networks

application development

composed of systems analyst and programmers who handled information systems design, development, and implementation.

DFD

data flow diagram

systems requirement document

describes management and user requirements, cost and benefits, and outlines alternative development strategies

process model

describes the logic that programmers use to write code modules

BPR is not

downsizing, restructuring, reorganizing, automation, new technology, etc. It is he examination and change of five components of the business.

To develop a strategic plan, top managers also need information from outside the company such as

economic forecasts, technology trends, competitive threats, and governmental issues

preliminary investigation

evaluate an IT related business opportunity or problem

Hardware consists of

everything in the physical layer such as -servers -workstations -networks -telecommunications equipment -fiber-optic cables -handheld computers -scanners -digital capture devices

Information systems have five key components:

hardware, software, data, processes, and people

Application software includes

horizontal & vertical systems

User productivity systems

include: email, voice mail, fax, video web processing, database, spreadsheets

knowledge worker

includes professional staff members such as systems analysts, programmers, accountants, researchers, trainers, and human resource specialists.

requirements modeling

investigate business processes and document what the new system must do to satisfy users by performing fact finding using techniques such as interviews, surveys, document review, observation, and sampling.

Business model

is a graphical representation of one or more business processes that a company performs, such as accepting an airline reservation, selling a ticket, or crediting a customer account.

horizontal systems

is a system such as inventory or payroll application that can be adapted for use in many different types of companies

Business profile

is an overview of a company's mission, functions, organization, products, services, customers, suppliers, competitors, constraints, and future direction

vertical system

is designed to meet the unique requirements of a specific business or industry, such as a Web-based retailer, a medical practice, or a video chain.

Regardless of the development strategy

people, tasks, timetables, and cost must be managed effectively using project management tools

application software consists of

programs that support day to day business functions and provide users with the information they require. it can serve one or thousands of users.

structured analysis

represents the system in terms of data and the processes that act upon that data

groupware

runs on a company intranet and enable users to share data, collaborate on projects, and work in teams.

Systems analysts need to consider

salary, location, and future growth potential when making a career decision

agile/adaptive methods

stresses intense team based effort. breaks down the development process down into cycles or iterations that add functionality. attempts to reduce major risk by incremental steps in short time intervals.

quality asssurance

team that reviews and tests all applications and systems changes to verify specifications and software quality standards. usually reports to IT Management

software refers to

the programs that control the hardware such as -operating systems -security software -device drivers; printers; utility programs

Systems Analysis

the purpose is to build a logical model of the system the first step is requirements modeling Deliverable is the System requirements document

In the waterfall model

the results of each phase is called a deliverable, or end product. a disadvantage is that it does not emphasize interactivity among phases.

object oriented analysis

views the system in terms of objects that combine data and processes

Supplier Relationship Management (SRM)

where buyers, sellers, distributors, and manufacturers can offer products, submit specifications, and transact business.

scrum

which is actually a rugby term, phases overlap and the entire process is performed by one cross-functional team. like rugby the team goes downfield while passing the ball back and forth, compared with relay race, where one team member performs at a time.

Systems Support and Security

•A well-designed system must be secure, reliable, maintainable, and scalable •Most information systems need to be updated significantly or replaced after several years of operation

Systems Design

•Deliverable is system design specification •Management and user involvement is critical

Impact of the Internet

•E-Commerce or I-Commerce •B2C (Business-to-Consumer) •B2B (Business-to-Business) -EDI -Extensible markup language (XML) -Supplier relationship management (SRM)

Systems Planning

•Systems request - begins the process & describes problems or desired changes •Purpose of this phase is to perform a preliminary investigation •Key part of preliminary investigation is a feasibility study

A system is

•a set of related components that produces specific results

Data definition

•consists of basic facts that are the system's raw material

The IT department

•develops, maintains and operates a company's information systems

The essential components of an information system are

•hardware, software, data, processes, and people

Information

•is data that has been transformed into output that is valuable to users

A Mission-critical system

•is one that is vital to a company's operations

Systems analyst use

•modeling, prototyping, and computer aided systems engineering (CASE) tools

Three popular system development approaches are

•structured analysis, object-oriented analysis (O-O), and agile methods, also called adaptive methods

The SDLC model usually includes five steps

•systems planning •systems analysis •systems design •systems implementation •systems support and security

Systems analysts need a combination of

•technical and business knowledge, analytical ability, and communication skills

IT refers to

•the combination of hardware and software resources that companies use to manage, access, communicate, and share information