The System Development Life Cycle (SDLC)
The SDLC is an organized series of activities that are used
to plan, implement and analyze systems development projects.
The SDLC is divided into phases. The number of phases varies
from company to company, but usually ranges from 5 to 7 steps.
Let's look at a typical 5-step approach.
- Planning - A famous old saying is that no one plans
to fail, they fail to plan. Adequate up-front planning is
critical to the success of any project. Goals and objectives
that meet the needs of the end users should be established
at the start of a project. Ensuring everyone is on the same
page and working towards common goals is essential. Key steps
in the planning process are as follows:
- Review Project Requests - many projects may be
requested at the same time. Not everything can be done
at once. Usually a steering committee is established to
review project requests to ensure they meet appropriate
company goals and objectives.
- Prioritizing Requests - Once reviewed, requests
must be prioritized. It is rare that a company will have
the money and manpower resources to work on all approved
requests at the same time.
- Allocation of Resources - Appropriate resources
(cash, manpower, etc.) are allocated to approved projects.
- Identify the Project Development Team - Who's
going to participate on the project.
- Analysis - In the analysis phase, the first of many
feasibility analyses are performed. A project may be a fantastic
idea that will benefit the company. But that doesn't mean
that it is feasible to develop the project. Barriers such
as high costs, lack of manpower, lack of money, competing
products can all impact the feasibility of a project. You
must constantly evaluate a project's feasibility during all
phases of the SDLC because as conditions change, a project
may cease to be feasible. Typical steps in the Analysis phase
are as follows:
- Preliminary Investigation - This normally involves
developing a problem definition and taking an initial
look at the feasibility of the project.
- Detailed Analysis Activities - This involves
studying and documenting the current system, interviewing
users about their needs and recommending a solution to
the problem. Generally, these activities are performed
by the systems analysts, who generate a feasibility report.
- Design - In this phase, the actual system design
is developed, including input and output specifications, database
designs and program designs. Equipment and software development
tools needed for the project are also purchased in this phase.
The product of this phase is the Program Specification Package
which essentially is the blueprint the programmers will follow
in the implementation phase.
- Implementation - In this phase, computer programming
takes place (if necessaryƒthe decision may have been made
to purchase a ready-made program in the design phase). After
coding, the system must be installed and tested. End users
must be trained to use the system and the old system must
be replaced by the new system.
- Maintenance and Support - In this phase, the system
is monitored to ensure it is performing optimally. Bugs in
the system are identified and corrected. New enhancements
suggested by users are implemented. Also, a systems audit
of the planning and development activities surrounding the
system is performed. The objective of the audit is to determine
what went wrong (and right) with the development process so
that future plans can be modified accordingly.
Now let's take a closer look at the people who participate
in this process.
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