Unit 22 - Systems Analysis and Design
22.1 Learning Aim A – Principles of Systems Analysis and Design
Task A – 22.1
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A.P1 Explain the principles of software development models
Section Intro:
Software Development Life Cycle (SDLC) is a ontological process used by the software
industry to plan, design, develop, test, maintain and complete high-quality software in the
shortest possible production time and cost estimates. The primary goal of SDLC is to meet or
exceed client expectations, whilst following the ISO 12207 (which is the international
standard for software lifecycle processes. {By providing guidelines to ensure quality
assurance).
The idea behind SDLC originated in the 1950s-1960s; when computer science progressed
rapidly and the as a result the complexity and the scale of programming grew too. This in
turn led to the concept of structured programming. With time, structured programming
needed more professional and tactical development models to create high quality
software(s) and this sparked the beginnings of the SDLC.
Figure 1.0 shows a graphical representation of the
stages involved in a typical SDLC.
Key Drivers
,As they say there is a reason for everything, Systems Analysis also has a solid reason or
sometimes reasons for it to take place. These reasons are known as Key Drivers and there
are a variety of key drivers. For example:-
Need for Business Growth: Organisations use Systems Analysis when they decide that they
have reached a point where they can expand their business and seek additional profits. This
can be done digitally by upgrading their systems to make them more efficient and
productive or it can be physically which is to expand their business locally or internationally.
This typically happens by a systems analyst who gives advice on systems upgradation
(depending on the budget and resources available) and also provides business tactics and
strategies.
Almost all the known companies have gone through this process, for example let’s take the
tech giant Apple. It started in Steve Jobs’ (CEO) house garage and now it’s hard to find
anywhere without an Apple product.
Company Acquisition: This is heavily dependent on rivalry and chemistry in companies;
when companies decide to merge together (i.e. to get ahead at competition in the market)
or some other reason.
This is done by a systems analyst who checks for any compatibility issues in the two (or
more) companies and then makes suggestions based upon it.
A prime example of this is Pendleton College which now comes under Salford City College
which is an organisation that also takes responsibility over other sixth form colleges such as
Eccles Sixth form College.
Productivity Rate: The emerging trend of 2021. Although there are many ways to increase
productivity in an organisation or even as a individual but one that really stands out is using
Technology to work for you. This process is known as automation. Time and time again
automation has proven to exponentially increase productivity rates and save businesses. For
example, in the mid 1800s cash theft from the counter was a common problem, receipts
could be easily altered or discarded and there were no cameras, and no software to keep an
eye on your employees. This is when Henry Patterson, a resident in Ohio opened up a
business of coal mines in Ohio. There was little competition and the flow of customers was
steady, but his still business was struggling to stay afloat in the market. This is when he
realized his money was being stolen from him. To get around this, he discovered a new
invention of his time called Ritty’s Incorruptible Cashier. It was the first ever cash register
and it automatically locked the cash register after transaction took place and thus receipts
couldn’t be altered with. This resulted in the business not only running smooth but also
saving $5,000, equivalent of $100,000 today! A good systems analyst would always ask
themselves if the task can be automated.
Legal Requirements: There might be a need for systems analysis for existing businesses,
whose owners/managers need to make sure that they are meeting all the legal
requirements of the country they are operating in. For instance, a company that wants to
expand their business internationally, (in this case in the UK) then they would have to make
, sure that there company meets the criteria for legal requirements like the General Data
Protection Act.
Stages Explained:
Purpose and what happens with examples
Stage 1: Planning and Requirement Analysis
The planning phase in a typical SDLC is about specialist(s) collecting precise requirements
from the client(s) to first identify and later on form a fine-tuned solution to their needs, as well
as identifying potential risks.
From a Business point of view, the three fundamentals to be vitally collected from the client
are:-
♦ Time
♦ Resources
♦ Budget/Costs
After collecting the specific needs, financial and availability estimates from the client, the
specialists can then move onto the final phase of this stage, which is to conduct the
feasibility study of the project, which would identify all the assets and the liabilities of the
project to assess the overall project viability.
It is obligatory to elucidate any misconceptions or unclarities for any requirements in this
stage, as this will be the building block of the whole project.
Stage 2: Defining Requirements
The purpose of the second stage is to build upon previous data and now move onto provide
a framework of the project; the radius of the problem and to identify multiple possible
solutions.
Developing upon the requirements collected in the first stage, this is where the project plan
is originated, and for a project plan to be successful it has to:-
Identify
Prioritize
Assign
The tasks and the resources required to build the grey structure of a project that they would
be working upon, for example the number of computers needed.
Stage 3: Designing the Product Architecture
In this stage, the project takes off from the ‘planning’ phase and begins to get in motion. This
stage starts after the client has agreed and signed off on the system for the previous stage,
stage 2; which allows the team to start building and creating.
The main focus of this phase is to determine how data will flow and be stored. The data is
created on graphical and statistical figures for analysis like Gantt Charts, Databases and
Spreadsheets etc. The team then decides on the most efficient way for the data to move
and be stored. One of the most common examples can be the use of SQL (structured
query languages) databases.
