Chapter 8 Technology of Information Systems

8/9/2019 Chapter 8 Technology of Information Systems

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TECHNOLOGY OFINFORMATION SYSTEMS

Prof. JG Sheshasaayee


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Learning Objectives

Technology Scope, Supporting IS and MIS

Processing of Data, Transaction, Application and

Information for MIS Application of CASE Tools

IT, a Strategic decision

Analytical study and evaluation of IT solutions Relevance of IT and MIS design


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Introduction

The development of modern Information system is a

complex process

IT needs knowledge, knowhow, skills and technology

Online real time systems demand thorough

understanding of the business

As the business processes are getting automated the

IS are undergoing cultural changes The business management process has changed

from function management to process management.


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Contd.,

The organization culture also changed from

centralized, bureaucratic, authority structure to

work-group culture where members were trained

and empowered to make decisions

The nature of business is such that a lot of initiative

of the user is expected to decide his own

information needs at a given point of time Due to this, a change in the architecture of

Information systems is required.


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Data Processing

Data is the smallest atomic entity in the IS which is

basic to build the IS

The character of data decides the quality of

information it offers to the user

In any IS significant care is taken in building the

data as a first level input to the system

The data is built through data design and modelingprocess which provides specification and character

to the data.


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Contd.,

Data processing is handling raw data in a

systematic manner to confirm the data quality

standards and determined by the designer of the IS

The atomic data entity is defined as a value

attached to an attribute which has a character,

meaning and presentation providing specific

message and understanding to its user The specification of data means determining its

manner of presentation, its value, specific or in

limits, whenever possible.


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Contd.,

Data processing means, each entity in Information

processing system is processed to confirm its

specification, character and validity.

The system supports the user through checks and

controls by responding and communicating errors

for correction

In the data processing stage, the system would pointout errors of wrong specification, errors of value,

errors in validity, etc.


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Contd.,

A systematic approach calls for determining

definition, model, character, value and its aspects,

its purpose and them making use of this knowledge

in processing before it is accepted in the databasesystem as a permanent input

The data needs to be designed by fixing its

character, value and structure and then be used it indata processing to control its acceptance for further

use.


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Contd.,

Data processing means following steps to be

implemented before the data is accepted in the

system for usage:

Confirming the character, structure and presentation

data design

Checking the value of the data such as single

specification value, range of value and limit value

ranges

If a non-conformance is seen, point out the error and

seek corrective response before the processing control

shifts to a new field.


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Transaction Processing

A transaction is processed with reference to the

business rules

The rules may be directly related to the transaction

or it may have some relation and association with

other transactions

The transaction is processed for adherence to

business rules, correctness and consistency of datavalues and for validity of transaction

The next check is to confirm internal consistency,

correctness and completeness of the data.


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Contd.,

The third check is for validity of the transaction

itself for its use in application and system processing

The validity of the transaction is checked against

the conditions present outside the domain of

transaction.


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Application Processing

Application processing is designed to process more

than one type of transactions to bring out the

specific business results in one or more business

functions

This processing is carried out once the transaction is

processed for its validity

The application processing means the use oftransaction data bringing out a particular status

The application could be designed to change the

number of different files holding a variety of

information.


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Contd.,

The application can be designed for status updation

and the status triggered actions in the related field

of the application

The scope of application processing can be made

diverse by incorporating different transactions from

the same application area or associated areas

The advent of communication technology and itsembedded use in application processing extended its

scope beyond the boundaries of the organization.


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Contd.,

The application can be designed for processing the

results, updation of the business status, for

triggering predefined actions and also

communicating with the affected agencies locatedwithin and outside the organization

The quality of application design will depend on

the inputs provided through transaction processingand data processing.


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Information System Processing

The system is defined as a product made up of

several applications set in orderly manner to

produce a higher level information output different

than the output of the application processing

Applications which are used for system processing

are the finance transaction accounting, the fixed

asset processing, the receivables and payablesprocessing, the sales and purchase accounting

It provides an insight into the funds flow, the sources

and the uses of funds, profitability and productivity

of the business.


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Contd.,

It throws light on growth, through trend analysis

The understanding of the business in terms of its

orientation, focus, CSF and knowledge of mission

critical application is absolutely essential for

effective system design

The basic management functions are same, i.e.,

finance, materials, production or service, personneland sales, etc., in all the business.


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Contd.,

These functions are executed in different manner on

account of the following factors:

Nature of business (trading or manufacturing)

The type of business (product or service)

The complexity of business (multiple locations, divisions,

products, etc.)

Management style (autocratic, participative) Decision Making (centralized, decentralized, and

empowered)

Quality of the organization and the people (learning

and positive proactive work culture).


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Contd.,

The entire work of ascertaining the information

needs to determination of the system design and

architecture is called System Engineering

System engineering not only deals with applications

and transactions but also with the various

technologies which are used in the system

implementation Data acquisition technologies

Processing architecture

Communication


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System Engineering Scope

Data Transaction Application System

Data

AcquisitionProcessing Networking Communication

System Engineering

Design

Application


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Contd.,

The IS processing, uses the system engineering

methodologies which are capable of dealing with

the data acquisition technologies, processing

technology and architecture, networkingtechnologies and communication

The total realistic solution is possible if the system

design in IS processing is a real time system The real time systems are open in nature having a

relational exchange with external world realities.


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Contd.,

The real time systems integrate the hardware/software, human and databases to capture data,validate transactions, process applications and executethe system to produce a business result

The real time system trigger an action as a response tothe external world events

To achieve this, the system processing requires a highspeed data acquisition and control, a high speedtransaction processing, an appropriate applicationprocessing and highly responsive and sensitive systemdesign and architecture

The system processing design is concerned about theperformance, which is a result of speed, accuracy and

reliability.


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TQM of Information System

The objective of TQM in IS design is to assure thequality of information

This is done by ensuring, verifying, and maintaining

software integrity through an appropriate methodologychoice amongst the technology, design and architecture

It institutes appropriate procedures with checks andcontrols in all the processes of IS development

It ensures that the scope and the objective of thesystem, choice of the design architecture anddevelopment methodology and quality ensuring theprocesses and planned implementation methodologiesare correctly chosen.


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Contd.,

The quality of the information will be rated high if it

assures:

A precise and an accurate information

A high level response in an interactive processing

User friendly operations

Reliability of information and

An ease of maintenance The user satisfaction is the single most important

measure of quality assurance and is highest if it

meets information needs on a continuing basis in a

dynamic environment.


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Contd.,

TQM ensures that the IS design is flexible, bug free

and easy to maintain with the changing needs

In the TQM application to IS, the technologies play

a vital role, which has two parts:

The current technologies database management,

distributed data processing, object orientation, parallel

processing, data warehousing and replication, networks

and communication

The emerging technologies Internet/Intranet, EDI and

E-mail, Groupware, Client/server, multimedia, video,

image processing, imaging systems, KBS, CASE.


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Contd.,

James W. Cortada measures the quality of

information by seven parameters

They are flexibility, maintainability, reusability,

integration, consistency, usability and reliability

The TQM approach to the IS development ensures

satisfactory level attainment of these parameters

through the implementation of various strategies inthe process of development.


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Contd.,

The SQA is an essential activity to ensure the

attainment of quality goals

The activity comprises:

1. Application of the proven methods and tools

Requirement Analysis

Defining the scope and the problem

Modeling and prototyping

Finalizing the software requirement specifications

Configuring the hardware and software platforms.


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Contd.,

2. Technical review to

Detect errors in the functionality and its logic

Confirm that the software meets the basic system

objectives Confirm that it meets the predefined standard in all the

areas

Confirm that uniform application of methods and

technologies.


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Contd.,

3. Testing to

Detect errors at the data level

Ensure the execution of known functionality

Ensure internal working of the software Ensure the execution on conditions and subsequent actions

Confirm the integration process

The testing is done at the data level, transaction level,

application level and the system level The normal practice is to develop a test plan and

procedure to check the software from all the angles.


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Contd.,

4. Version changes control to

Ensure that the change does not alter the original assured

quality

Confirm that no bugs are introduced in the software Ensure that proper documentation is made as changes

introduced

5. Record keeping to

Establish knowledge and know-how on reviews, audits,changes, testing for future reference and use in bug fixing.


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Human Factors and User Interface

The use of IS is made through an interactive process

between the human beings and the system through

which the IS is activated, operated and closed

The use of IS is accomplished also through a visualmode

The human response differs from person to person

owning to the varying human perception The quick human response neutralizing the human

perception difference is the requirement of the user

interface.


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Contd.,

The first step in the interaction is extracting the

information from display

The speed of the extraction of information will

depend on the display design which includes thetext size, the font type, the text length, etc.

The next factor is skill levels and behavioral

differences amongst the various users The differences in the skill levels and behavioral

differences occur due to the difference in the

training, experience and exposure of the people in

the business operations.


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Contd.,

The behavioral differences occur due to personality

variations and personality traits

The interface should be built looking into the skills,

knowledge, experience and the quality of thepeople in the majority of the users

The UI is expected to assist the four tasks which are

basic to all software systems: They are communication, dialogue, system execution

and control of the process.


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Contd.,

In the latest technology advances, the interface

characteristics are more or less standard

The system execution will be handled through a

menu driven feature

It will provide a window based help for reference

or local processing

The interface will have a point and pick facility topick the icons which could be general or can be

built for the system.


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Contd.,

While designing the user interface the issues which

should be addressed squarely are:

the response time of the system affecting the

performance user help facilities, bringing comfort and understanding

in the system operations,

error information handling for better management of

the quality and

command labeling for ease or understanding and

usage.


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Contd.,

An interface should also provide a context sensitive

help and use known verbs for describing the

commands

Only the relevant information to the current contextshould be displayed

A meaningful error message seeking the right

mental response should be constructed Guidelines on data entry processes

Interface should take default values where input is

not provided.


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Configuration Design

The details of the IT, such as architecture, RDBMS,

communication, storage media and OS are also

strategic to the success of the MIS

Following features are considered while configuringthe IT platform design

Data type: Words, numeric, image and voice

Data volume: The volume decides the disk options Storage capacity: The online storage depends on the

processing needs.


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Contd.,

I/O Operations: These would decide the controllers and

the speed of I/O processing

Data Sharing: If the data is to be shared across the

databases, then the storage capacity will be decidedbased on the size of the databases

Process Speed: The speed needed for processing will

decide the CPU, memory and the processing

architecture RDBMS and 4GL: These will be chosen on the basis of

the volume, special handling of the data and the level

of security and the integrity required.


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Contd.,

Query Processing: This decides the SQL and 4GL

Communication Protocols: It different platforms need

to be connected, then the software such as the TCP/

IP needs to be considered

Interface and Gateways: These will be decided on

the basis of data transfer needs between the

locations and between the hardware-softwareplatforms

Security and Integrity: This will decide the

hardware, software and the OS.


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Contd.,

Languages and Packages: The requirement is of a

special language and packages besides the main

software

The IT choice is translated into a variety of detailsbased on the above factors

When all the factors and the associated choices of

the IT details are worked out, we can say that theconfiguration of the computer system is designed.


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Evaluation and Feasibility of IT

Solutions

The selection criteria for evaluation would have

different dimensions to be satisfied simultaneously:

These dimensions are:

Technical

Operational

Financial


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Technical Evaluation

Technical evaluation deals with the testing

parameters, such as data transfer needs, the

response level, the successful connectivity of the

different hardware and the degree of meeting theoverall system performance standards

Technical evaluations can be carried out first by

studying the literature of the product in detail and

then by conducting brain storming sessions with the

vendors specialists.


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Contd.,

All hardware and software details are configured

and the quality of each item is also decided using

the norms developed in a live experiment

Technical evaluation also confirms the IT approachto the information processing needs of the

organization

The issues like the centralized vs. distributed, theonline vs. the batch vs. the real time, the network vs.

the mini or the supermini are also evaluated.


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Contd.,

Technical evaluation considers the performance

related issues such as reliability, dependability,

performance on the volume scale, security, integrity

and autonomy, etc. Technical evaluation also helps to break down the

hardware on a time scale

It is necessary to select the latest technology in allareas of Information processing.


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Operational Feasibility

The operational feasibility evaluation considers the

people-related issues and whether the systems and

procedures of the organization are complementary

and conducive The choice of technology determines automatically

the caliber, the competence, the knowledge of the

people

The shortcomings would be the lack of requisite

qualification and the subject knowledge, the ability

to absorb the technology, and use it efficiently and

effectively.


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Contd.,

Other areas affected would be the systems and the

procedures currently operating in the company

The shortcomings are observed right from the

absence to the inefficient systems and procedures

The modern IT needs sophisticated back-up of the

data at a requisite point and time

The environment must be conducive to supportproper implementation of a new information

technology.


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Financial Evaluation

All business investments are evaluated in terms of

return on the investment (ROI) or certain payback

period

They are also judged from budget considerations

The IT investments are difficult to judge on the ROI

as the returns would be intangible

The best approach is to judge the investment interms of the value of information it gives on an

incremental scale.


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Contd.,

It would be advisable to examine the possibility of

scaling the hardware and software options

The budget restrictions can be handled by taking

the benefit of the scalable and the upgradeabletechnology

The scaling can be done on two scales

Horizontal relates to the quantity Vertical relates to the quality and coverage.


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MIS: Choice of the IT

The choice of the IT is a backbone of the MIS

It is a critical strategic decision affecting the

business and prospects

It affect the people, the processes and productivity

The success of the MIS lies in how the IT is

implemented in the organization

A lot depends on the people and their ability toaccept the new work style and the new work culture.


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Contd.,

All the implementations of the IT lead toorganizational transformation in the content andstructure

Human side should be aligned properly with the IT Risk of manipulating the IT beyond a limit to suit the

personnel

The IT changes are very rapid

The selection criteria includes scalable architecture,upgradeable software, an open system environment,communication capability through gateways andinterfaces and so on.

Chapter 8 Technology of Information Systems

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