The feasibility of the proposed system is considered.
This stage is also known as "the feasibility stage"
An initial look at the existing system to see how it can be improved or meet the needs of the end user
A feasibility report is produced at the end of this stage
Main Process Constraints
Time
Budget
Hardware Choice
Software Choice
Important Questions that should be answered in this stage
Can the need for a new system be justified?
Is it technically feasible and economically desirable to the end users?
Can the solution be designed and implemented within
the given constraints of timescale allocated and budget?
Will the solution have a positive impact on
the end users and will the new system
bring benefits
Will the solution fulfil all the needs and requirements of the end users
Design
The design stage follows a set of objectives (the
requirement specification) that have been defined in the
investigation and analysis stage
The methods of data capture that are going to be used have to be
considered to make sure that they are compatible with the new system
The preparation, input, process, output and storage of the
data must also be considered
This also covers such activities as the design of the user
interface and the screen layout
The structure of the data must be
defined together with the processing and
the validation routines that will be used
Development of any user feedback
requirements (error messages) should be
linked with this
The design of the queries and reports that
have to be identified as requirements during
the investigation stage needs to be
considered as well
The main output from this stage is
the design specification
Doumentation
The documentation that gets passed to the end user includes
Detailed program specifications
Recovery procedures
Operating procedures
User manuals
Test plans, data and logs
Security details
Version details
Technical details for associated hardware
Investigation and Analysis
This stage uses the feasibility report as its main input
The full nature of the problem is investigated in this stage
Methods of investigating the current system
Questionnaires
Interviews
Meetings
Document Analysis
Observations
The results of the investigation have to be fully analysed to
gain a full understanding of the current system
If the investigation is incomplete, the new system may not
cover all the issues with the current system
Therefore, the new system may not benefit the organisation
The user requirements have to be defined during this stage
The requirements are agreed with the client and will
form the basis for the rest of the system lifecycle
The agreed needs/ requirements are the output of this stage (the
requirement specification)
The requirement specification has to be constantly referred to to make sure
that the new system meets all of the criteria of this
Implementation
This stage is also known as the development stage
This stage uses the design specification as its main input
During this stage, programmers will create the code required for the software solution.
This includes the development of the
user interfaces and outputs, which
were designed in the design stage
Any macros, processing and queries that are
required by the client must be developed as well
The main output of this stage will be working software code that is ready to be tested
Testing
Two main functions of this stage
If there are any bugs or
errors in the code
If the system correctly meets the
defined user requirements
A well-defined and comprehensive test plan must be produced
The test plan must be followed and results must be documented
This stage can be vey expensive and time
consuming but if it carried out correctly and
throughly there will be fewer bugs and issues
with the new system
Evaluation and Maintenance
This is the final stage of the system lifecycle.
This stage concludes the whole cycle and a report is
produced to summarise each stage of the project and all
finds, problems encountered.
Installation
Parallel
This type of installation is when the new system is run along
the existing system. This allows any persistent bugs with the
new system to be corrected without affecting the day to day
running of the company. Once all problems have been resolved,
the existing system will be withdrawn from operation and the
new system will run on its own
An example of this type of installation is self service checkouts in supermarkets
Phased
This type of installation is when a new system is introduced into the
company is stages ("phases"). This is done by running the new system
in certain departments or areas
An example of this is self service checkouts in supermarkets. This is because they were
introduced to a few shops to start with to see how consumers reacted to the change and then
converting the rest of the stores to the new system
This is still an ongoing process for some supermarkets because
not all of their stores are running the new system. In this case,
self service checkout system
Pilot
This method of installation is done by
introducing the system to one
department or store to see how it
works
There is less of a risk involved in this type of
installation because if the new system is
unsuccessful, it can be withdrawn easily with little
disruption
Direct
This type of installation is done
by introducing the new system to
the company in one hit. The
existing system is removed and
the new system is left to run on its
own.
This is a risky method of installation
because the new system may not work due
to undiscovered bugs or because users
may not be able to adapt fast enough to use
the new system