SYSTEM DEVELOPMENT LIFE CYCLE
Development of information system undergoes 5 stages,
CONCEPT OF IMPLEMENTATION
Implementation means constructing and putting the new system into
Creation of system based on analysis and design document.
Implementation refers to all of the organizational activities working
towards the ,
Routinization of an innovation.
Implementation activities are needed to transform a newly developed IS
into an operational system for end users.
Implementation is a process of
These steps are based on the design specification.
All the requirements of the system, such as input,
processing, output equipment etc. are provided by design
Documentation User Training
PLANNING THE IMPLEMENTATION
Activities required are
identified and sequenced
Time and cost estimation
for each activities are being
Plan and implementation
schedule are being made by
system analyst using
various tools like Gantt
charts, network diagrams
ACQUISITIONS OF FACILITIES AND SPACE
The IS to be implemented may be for,
This requires acquisition of facilities like office, computer
room, computer library etc.
Proper estimation of floor space requirement and roughs
layouts are to be prepared by MIS manager.
• Where no old system is in existence
• New systems are to be implemented
• Information system needs to be
modified to great extent
• New system needs to be developed
ACQUISITION OF HARDWARE & SOFTWARE
Large business firms or government agencies
formalize there hardware and software requirements
by listing them in a document called RFP (Request for
proposal) or RFQ (Request for quotation).
CODING & TESTING
Physical design created by the system designer team are
turned into working computer code by the programming
Depending on the size and complexity of the system, coding
can be an involved, intensive activity.
Immediately after coding process has begun, testing can be
System testing involves,
Testing and debugging software,
Testing Website performance, and
Testing new hardware.
It’s important part is, review of prototype of displays,
reports and other output.
There are 2 types of documentation: -
Detailed information about
specification, it’s internal
working and its
Consist of written or other
visual information about
an application system,
how it works and how to
Educate and train management, end users, customers, and
other business stakeholder.
Proper user training is an important factor in promoting the
required culture and thus ensuring the acceptance of new
METHODS AND AIDS OF TRAINING: -
INSTALLATION / CONVERSION
Installation or changeover is the event of switch-over from
the old system to the new system, which takes place after
the system is tested and found reliable.
In new organization, there are no old systems to
replace, so for fresh implementation, new developed and
tested systems are installed as it is.
In existing organizations, old systems are replaced with
the new developed systems.
So for replacement implementation, there are 4 conversion
Slam Dunk or Cold-turkey
Old system is completely
dropped out, and new system
is turned on in its place.
High risk of failure
Should be considered only in
Old system is not dropped out
at once, Both old and new
systems are simultaneously
Until the end-users and project
coordinators are fully satisfied
that the new system is
Old System New System
Use where the new system
is to be installed in multiple
It allows for conversion to
the new system, either a
direct or parallel method, at
a single location.
Less risky in terms of any
loss of time or delay in
Gradual Conversion or
Cutover by segments.
The new system is
implemented in many
phase. Each phase is
carried out only after
of previous phase.
Very less risk is involved.
New SystemOld System
New SystemOld System
Implementation of IS may result in many changes in
POTENTIAL AREAS OF IMPACT: -
Centralization of Authority
Resistance to change
CONCEPT OF CHANGE MANAGEMENT
Information system development and implementation
projects often tend to end in failure.
changes are difficult to predict, and tend to occur with
growing frequency, change management is becoming an
increasingly significant subject.
Change management involves analyzing and defining all
changes facing the organization, and developing programs
to reduce the risks and costs, and to maximize the benefits
It is a structured, disciplined approach that facilitates the
adoption of new and modified of various groups and
individual within the system.
CHANGE MANAGEMENT PROCESS
The change management process is the sequence of steps or
activities that a change management team or project leader
would follow to apply change management to a project or
change. a change management process that contains the
following three parts.:
Preparing for change (Preparation, assessment and
Managing change (Detailed planning and change
Reinforcing change (Data gathering, corrective action and
CONTROL IN INFORMATION SYSTEM
To ensure secure and efficient operation of information systems, an
organization institutes a set of procedures and technological measures
Implemented through: -
Control must be thought about through all stages of information
systems analysis, construction and maintenance.
TYPES OF CONTROL
Physical Controls: -
It refer to the protection of computer facilities and other IS
resources. This includes protecting computer hardware,
computer software, database, computer networks.etc
Technical Controls: -
controls which are implemented in the application of IS itself.
These types of controls include access controls, data security
controls, communication controls etc.
Administrative Controls: -
controls which include clear guidelines, policies of the
organisations with regards to the use and deployment of IS
resources are very important in protecting ISs.
For example: - email policy, internet use policy, access
privileges of employees,
General Controls: -
These controls are implemented so as to ensure that
ISs are protected from Various potential threats.
For example: - system development controls like
budgeting, schedule, quality etc.
Application Controls: -
the application controls, as the name implies, are
embedded within the application itself. These controls
are usually written as validation rules. These controls
are popularly known as input controls, processing
controls, and output controls.
IS SECURITY THREATS
1. Human errors/failures: - unintentional errors made by
2. Manipulation of data/systems: - deliberate acts of some
persons or organisations, designed to harm the data or
information systems of an organisation.
3. Theft of data/systems: - deliberate attempt of some person to
steal the important data of an organisation.
4. Destruction from virus: - A Virus is computer code that has
been inserted into a piece of software. Upon execution of the
software the virus is also executed.
5. Natural disasters: - forces of nature that cannot be prevented
or controlled. Such as fire, flood, earthquake, Lightning etc.
1. Preventive strategy: - controls that would help prevent errors
from occurring, deter criminals from attacking the system, and
deny access to unauthorised people.
2. Detection strategy: - It may not be feasible to prevent the IS
systems from all hazards, cause it’ll only detect the threat.
3. Minimum losses strategy: - minimising of losses once a threat
4. Recovery strategy: - A recovery plan, that explains how to fix a
damaged information system as quickly as possible, must be in
5. Corrective action strategy: - The damaged system must be
corrected immediately so as to prevent the problem form