Copyright Irwin/McGraw-Hill 1998 1 Information System Building Blocks Prepared by Kevin C. Dittman...

Prepared by Kevin C. Dittman for

Systems Analysis & Design Methods 4ed

by J. L. Whitten & L. D. BentleyCopyright Irwin/McGraw-Hill 19981

Information System Building Blocks

Introduction

The chapter will address the following questions: What is the difference between data and information? What is the the product called an information system? What are six classes of information system applications and how

they interoperate? What is the role of information systems architecture in systems

development? What are four groups of stakeholders in information systems

development and the unique role of the systems analyst in relation to the four groups?

Could you be able to recognize categories of systems users and managers who become stakeholders in systems development?





Introduction

The chapter will address the following questions: Can you differentiate between a perspective and a view as it

relates to information systems architecture? What are four perspectives of the DATA focus for an information

system? What are four perspectives of the PROCESS focus for an

information system? What are four perspectives of the INTERFACE focus for an

information system? What are four perspectives of the GEOGRAPHY focus for an

information system?




Information System Building BlocksA Review of Fundamentals of

Information Systems

What is the difference between Data and Information? Data are raw facts about the organization and its business

transactions. Most data items have little meaning and use by themselves.

Information is data that has been refined and organized by processing and purposeful intelligence.

Information Systems transform data into useful information.

An information system is an arrangement of people, data, processes, interfaces, and geography that are integrated for the purpose of supporting and improving the day-to-day operations in a business, as well as fulfilling the problem-solving and decision-making information needs of business managers.





Transaction Processing Systems Business transactions are events that serve the mission

of the business. Transaction processing systems are information system

applications that capture and process data about (or for) business transactions. They are sometimes called data processing systems.

A Review of Fundamentals ofInformation Systems





Management Information Systems Management Information Systems supplement

transaction processing systems with management reports required to plan, monitor, and control business operations. A management information system (MIS) is an information

system application that provides for management-oriented reporting, usually in a predetermined, fixed format.






Decision Support Systems Decision Support Systems are concerned with

providing useful information to support the decision process. A decision support system (DSS) is an information system

application that provides its users with decision-oriented information whenever a decision making situation arises. When applied to executive managers, these systems are sometimes called executive information systems.

A DSS is designed to support unstructured decisions.






Information Systems

Expert Systems Expert Systems are an extension of the decision support

system. An expert system is an information system application that

captures the knowledge and expertise of a problem solver or decision maker, and then simulates the ‘thinking’ of that expert for those who have less expertise.

Expert systems are implemented with artificial intelligence technology, often called expert system shells.





Information Systems

Office Information Systems Office Information Systems are concerned with getting

all relevant information to all those who need it. Office information systems support the wide range of

business office activities that provide for improved work flow and communications between workers, regardless of whether or not those workers are physically located in an office.

Office information systems may use the following technologies:

• Electronic forms technology

• Work group technology

• Electronic messaging technology

• Office automation suite technology

• Imaging technology





Information Systems

Personal and Work Group Information Systems Personal and Work Group Information Systems

typically are built using personal computer technology and software. Personal information systems are those designed to meet the

needs of a single user. They are designed to boost an individual’s productivity.

Work group information systems are those designed to meet the needs of a work group. They are designed to boost the group’s productivity.





Transaction Processing

System

Executive Information

System

Management Information

System

Decision Support System

Expert System

Personal Information

System

Office Information

System

Business Database

Expertise Database

Business Data Warehouse

Data

Data

Captured data

Data and

messages

Read-only data

Data snapshots

Read-only data

Data

Rules

Data

Problem

Decision support

information

Executive inquiry

Executive information

Any Manager

Any Decision Maker

or Executive

Information need

Management information

Any Relevant

User

Problem

Solution

Any User

Transaction Data

Transaction information

Communications between users

and within groups

Any User

Personal data

Shared data

Personal Files &

Databases

Personal data

Personal information




Information System Building BlocksA Framework For Information

Systems Architecture

What is an Information Systems Architecture? An information systems architecture provides a unifying

framework into which various people with different perspectives can organize and view the fundamental building blocks of information systems.

Stakeholders have different views of the system and each has something “at stake” in determining the success of the system.

Stakeholders can be broadly classified into four groups: System Owners System Users System Designers System Builders




Information System Building BlocksINFORMATION SYSTEMS FRAMEWORK

SYSTEM

ANALYSTS

SYSTEMBUILDERS

SYSTEMDESIGNERS

SYSTEMUSERS

SYSTEMOWNERS

DataTechnology

INFORMATION SYSTEM COMPONENTS(the actual, technical implementation of the system)

INFORMATION SYSTEM DESIGN(HOW the system will be implemented using technology)

INFORMATION SYSTEM REQUIREMENTS(WHAT the system "is" and "must do" independent of technology)

INFORMATION SYSTEM SCOPE(purpose and vision; goals and objectives; costs and benefits)

INFORMATION SYSTEM FOCUSES

NetworkingTechnology

InterfaceTechnology

SoftwareTechnology




Information System Building BlocksPerspectives - The People Side of

Information Systems

What are Information Workers? The term information worker (also called knowledge worker)

was coined to describe those people whose jobs involve the creation, collection, processing, distribution, and use of information.

System Owners System owners are an information system's sponsors and chief

advocates. They are usually responsible for budgeting the money and time to develop, operate, and maintain the information system. They are also ultimately responsible for the system’s justification and acceptance.





Information Systems

System Users System users are the people who use (and directly benefit from)

the information system on a regular basis – capturing, validating, entering, responding to, storing, and exchanging data and information.

There are many classes of system users including: Internal Users

• Clerical and service workers• Technical and professional staff

– Knowledge workers are a subset of information workers whose responsibilities are based on a specialized body of knowledge.

• Supervisors, middle managers, and executive managers





Information Systems

System Users There are many classes of system users including: (continued)

Remote and Mobile Users External Users





Information Systems

System Designers System designers translate users' business requirements and

constraints into technical solutions. They design the computer files, databases, inputs, outputs, screens, networks, and programs that will meet the system users' requirements. They also integrate the technical solution back into the day-to-day business environment.





Information Systems

System Designers Today’s system designers tend to focus on technical specialties.

Database designers have a DATA focus. Software engineers and programmers have a PROCESS (or

program) focus. Personal computing specialists and systems integrators usually

have an INTERFACE focus. Network and telecommunications specialists have a

GEOGRAPHY focus.





Information Systems

System Builders System builders construct the information system components

based upon the design specifications from the system designers. In many cases, the system designer and builder for a component are one and the same.

The applications programmer is the classic example of a system builder.





Information Systems

The Role of the System Analyst For the system owners and users, the analyst typically constructs

and validates their views. For the system designers and builders, the analyst (at the very

least) ensures that the technical views are consistent and compatible with the business views.




Information System Building BlocksBuilding Blocks - Expanding The Information System Framework

There are at least four distinct focuses in a system. DATA - the raw material used to create useful information. PROCESSES - the activities (including management) that carry

out the mission of the business. INTERFACES - how the system interacts with people and other

systems GEOGRAPHY - where the data is captured and stored; where the

processes happen; where the interfaces happen.





SYSTEM

ANALYSTS

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

SystemBuilders'views of

DATA

SystemDesigners'

views ofDATA

SystemUsers'

views ofDATA

SystemOwners'views of

DATA

DATAFOCUS

DataTechnology


PROCESSES

SystemDesigners'

views ofPROCESSES

SystemUsers'

views ofPROCESSES


PROCESSES

PROCESSFOCUS


INTERFACES

SystemDesigners'

views ofINTERFACES

SystemUsers'

views ofINTERFACES


INTERFACES

INTERFACEFOCUS


GEOGRAPHY

SystemDesigners'

views ofGEOGRAPHY

SystemUsers'view of

GEOGRAPHY


GEOGRAPHY

GEOGRAPHYFOCUS

NetworkingTechnology

InterfaceTechnology

SoftwareTechnology





SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

FOCUS ONSYSTEM

DATA

COBOL Program

Structure Chart

Data Flow Diagram

Decomposition Diagram

FOCUS ONSYSTEM

PROCESSES

FOCUS ON SYSTEM

INTERFACES

COBOLCompiler

onIBM 3090 MVS

InterfaceTechnology

NetworkingTelchnology

FOCUS ONSYSTEM

GEOGRAPHY

Marketing

Advertising

Orders

Sales

Cancellations Services

Check credit

Validate customer

Validate products

Release order

Customers

Orders

Products

order

customer number

valid order

order without valid

customer

credit

order with valid products

approved order

quantity in s tock

approved order

rejected order

prices

pick ing ticket

Or der P r ocessing

P r ogr am

P r ocess an Or der

Initiation Routine

S hutdown Routine

Get an Or der

Validate an Or der

File an Or der

Check Custom er

Cr edit

Check P r oduct

Data

Check Cr edit Data

Release an

Or der

Custom er s P r oductsOr der s

VALIDATE_AN_ORDER. REPEAT UNTIL NO_MORE_ORDERS PERFORM CUSTOMER_VALIDATIO REPEAT UNTIL NO_MORE_ORDER PERFORM PRODUCT_VALIDATI END REPEAT. PERFORM CREDIT_CHECK. IF CREDIT_CHECK 'BAD' THEN





Building Blocks of Data Data is the raw material used to produce information. Goal is to capture and store business data using database

technology.





SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

Database Programs

Database Schema

Data Requirements

Business Subjects

FOCUS ONSYSTEM

DATA

FOCUS ONSYSTEM

PROCESSES

FOCUS ON SYSTEM

INTERFACES

SoftwareTechnology

InterfaceTechnology


FOCUS ONSYSTEM

GEOGRAPHY

Customers order zero, one, or more products. Products may be ordered by zero, one, or more customers.

CUSTOMER customer_no [Alpha (10)] INDEX customer_name [Alpha(32)] customer_rating [Alpha(1)] INDEX balance_due [Real(5,2)]

PRODUCT product_no [Alpha(10)] INDEX product_name [Alpha(32)] unit_of_measure [Alpha(2)] unit_price [Real(3,2)] quantity_available [Integer(4)]

ORDER order_no [Alpha(12)] INDEX order_date [Date(mmddyyyy) CUSTOMER.customer_no

ORDER_PRODUCT ORDER.order_no PRODUCT.product_no quantity_ordered [Integer(2)

CREATE TABLE CUSTOMER (customer_no CHAR(10) NOT NULL customer_name CHAR(32) NOT NULL customer _rating CHAR(1) NOT NULL balance_due DECIMAL(5,2) CREATE INDEX cust_no_idx on CUSTOMER CREATE INDEX cust_rt_idx on CUSTOMER

CUSTOMER customer-no customer-name customer-rating balance-due

PRODUCT product-no product-name unit-of-measure unit-price quantity-available

ORDER order-no order-date products-ordered quantities-ordered





Building Blocks of Processes PROCESSES deliver the functionality of an information system. Processes perform the work in a system. The goal is to automate appropriate processes with software

technology.





SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

Database Structures

Database Scehma

Data Requirements

Business Subjects

FOCUS ONSYSTEM

DATA

Application Programs

Application Schema

Business Process Reqts.

Business Functions

FOCUS ONSYSTEM

PROCESSES

FOCUS ON SYSTEM

INTERFACES

Software(and Hardware)

Technology

InterfaceTechnology


FOCUS ONSYSTEM

GEOGRAPHY

Marketing

Advertising

Orders

Sales

Cancellations Services

Order Processing

Program

Process an Order

Initiation Routine

Shutdown Routine

Get an Order

Validate an Order

File an Order

Check Customer

Credit

Check Product

Data

Check Credit Data

Release an

Order

Customers Products Orders


Check credit

Validate customer

Validate products

Release order

Customers

Orders

Products

order

customer number

valid order

order without valid

customer

credit


approved order

quantity in s tock

approved order

rejected order

prices

pick ing ticket





Building Blocks of Interfaces There are two critical components to information system

Interfaces. Information systems must provide effective and efficient

interfaces to the system’s users. Information systems must interface effectively and efficiently

to other information systems, both within the business, and increasingly with other businesses’ information systems.

Technologies exist to implement interfaces. Technologies exist that can almost completely eliminate human

error or intervention. Technologies exist for system integration.





SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

Database Structures

Database Scehma

Data Requirements

Business Subjects

FOCUS ONSYSTEM

DATA


Application Schema


Business Functions

FOCUS ONSYSTEM

PROCESSES

Component Programs

Interface Schema

Input/Output Reqts.

System Context

FOCUS ON SYSTEM

INTERFACES


Technology

InterfaceTechnology


FOCUS ONSYSTEM

GEOGRAPHY

Order Management

SystemCustomer

Accounts Receivable Database

Warehouse

Bank

OrderPicking Order

Credit

Credit Voucher

Order Form

Help +

Customer Form

Product Lookup

Logon

New Customer

New Order

Order Accepted

Change of

Address

First Order

Request Order Help

Order Help Complete

Request Product Lookup

Request Product Lookup Help

Product Lookup Help Complete

On Event Help.ButtonClick Do Change Focus HelpDialog On Event OKButton Do Begin {proecdure} End On Event CancelButton Do

F ire c ra c k e r Sa le s





Building Blocks of Geography Information systems geography describes:

the distribution of DATA, PROCESSES, and INTERFACES (the other building blocks) to appropriate business locations

the movement of data and information between those locations The inclusion of GEOGRAPHY in the framework is driven by the

trend towards distributed computing. Distributed computing is the decentralization of applications

and databases to multiple computers across a computer network.





Building Blocks of Geography The most popular application of distributed computing is called

client/server computing. In a client/server computing application, information system

building blocks are distributed between ‘client’ personal computers and ‘server’ shared computers. The clients and servers effectively interoperate to share the overall workload.





Building Blocks of Geography Distributed computing is being driven by several trends.

Organizations that can gain faster access to critical information have a competitive advantage.

Organizations that can extend their information systems to include their customers and suppliers have a competitive advantage.

Organizations operate in more locations, national and international, then ever before.





SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

Database Structures

Database Scehma

Data Requirements

Business Subjects

FOCUS ONSYSTEM

DATA


Application Schema


Business Functions

FOCUS ONSYSTEM

PROCESSES

Component Programs

Interface Schema

Input/Output Reqts.

System Context

FOCUS ON SYSTEM

INTERFACES


Technology

InterfaceTechnology


Network Programs

Network Schema

Communication Reqts.

Operating Locations

FOCUS ONSYSTEM

GEOGRAPHY

EDI Cust

St. Louis

HQ

LA Office

Indy Ware- house

NY Office

West Customers

East Customers

Maintenance Records

Products Catalog

ordercatalog

changes

ship order

ship order ship order

credit credit

service

St. Louis Mainframe

Indy AIX Server

NT Server LA

NT Server NY

Communications Controller

PBX

Enternet LAN AIX/Lan Manager

Ethernet LAN/NT

Ethernet LAN/NT

Client PC Client PC

Client PC Client PC

Create AccountType = SalesClerk Set OrderDir.Rights=full Set CustomerDir.Rights=full Set ProductDir.Rights=read Set OrderAppDir.Rights=copy





SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

Database Structures

any good DB course

Database Scehma

Chapter 12

Data Requirements

Chapters 5, 6

Business Subjects

Chapters 5, 6

FOCUS ONSYSTEM

DATA


any good programming course

Application Schema

Chapters 11, 16

Business Processes

Chapters 5, 7

Business Functions

Chapters 5, 7

FOCUS ONSYSTEM

PROCESSES

Component Programs

any good programming course

Interface Schema

Chapters 11, 13, 14, 15

Interface Requirements

Chapters 5, 13, 14

System Context

Chapters 5, 7

FOCUS ON SYSTEM

INTERFACES


Technology

InterfaceTechnology


Network Programs

any good data communication course

Network Schema

Chapter 11

Communication Reqts.

Chapters 5, 8

Operating Locations

Chapters 5, 8

FOCUS ONSYSTEM

GEOGRAPHY

CREATE TABLE CUSTOMER (customer_no CHAR(10) NOT NULL customer_name CHAR(32) NOT NULL customer _rating CHAR(1) NOT NULL balance_due DECIMAL(5,2) CREATE INDEX cust_no_idx on CUSTOMER CREATE INDEX cust_rt_idx on CUSTOMER

CUSTOMER customer-no customer-name customer-rating balance-due

PRODUCT product-no product-name unit-of-measure unit-price quantity-available

ORDER order-no order-date products-ordered quantities-ordered

Order Form

Help +

Customer Form

Product Lookup

Logon

New Customer

New Order

Order Accepted

Change of

Address

First Order

Request Order Help

Order Help Complete

Request Product Lookup

Request Product Lookup Help

Product Lookup Help Complete

On Event Help.ButtonClick Do Change Focus HelpDialog On Event OKButton Do Begin {proecdure} End On Event CancelButton Do

Create AccountType = SalesClerk Set OrderDir.Rights=full Set CustomerDir.Rights=full Set ProductDir.Rights=read Set OrderAppDir.Rights=copy

Customers order zero, one, or more products. Products may be ordered by zero, one, or more customers.

Marketing

Advert ising

Orders

Sales

Cancellat ions Services

Order Management

SystemCustomer

Accounts Receivable Database

Warehouse

Bank

OrderPicking Order

Credit

Credit Voucher

Check credit

Validate customer

Validate products

Release order

Customers

Orders

Products

order

customer number

valid order

order without valid

customer

credit


approved order

quantity in stock

approved order

rejected order

prices

picking ticket

Fi recracker Sal es

EDI Cust

St. Louis

HQ

LA Office

Indy Ware- house

NY Office

West Customers

East Customers

Maintenance Records

Products Catalog

ordercatalog

changes

ship order

ship order ship order

credit credit

service

CUSTO MER customer_no [Alpha (10)] INDEX customer_name [Alpha(32)] customer_rating [Alpha(1)] INDEX balance_due [Real(5,2)]

PRODUCT product_no [Alpha(10)] INDEX product_name [Alpha(32)] un it_of_measure [Alpha(2)] un it_price [Real(3,2)] quantity_availab le [Integer(4)]

ORDER order_no [Alpha(12)] INDEX order_date [Date(mmddyyyy) CUSTO MER.customer_no

ORDER_PRODUCT ORDER.order_no PRODUCT.product_no quantity_ordered [In teger(2)

Order Processing

Program

Process an Order

Initiation Routine

Shutdown Routine

Get an Order

Validate an Order

File an Order

Check Customer

Credit

Check Product

Data

Check Credit Data

Release an

Order

Customers Products Orders

St. Louis Mainframe

Indy AIX Server

NT Server LA

NT Server NY

Communications Controller

PBX

Enternet LAN AIX/Lan Manager

Ethernet LAN/NT

Ethernet LAN/NT

Client PC Client PC

Client PC Client PC






Summary

Introduction A Review of Fundamentals of Information

Systems A Framework For Information Systems

Architecture Perspectives - The People Side of

Information Systems Building Blocks - Expanding The

Information System Framework

Copyright Irwin/McGraw-Hill 1998 1 Information System Building Blocks Prepared by Kevin C. Dittman...

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