The Systems Development Life Cycle
October 19 – October 25

What is the SDLC:
o
When developing a new information system, there are many, many steps that
must be followed. The systems development life cycle (SDLC) is an attempt to
structure these steps (p. 278).
o
From the perspective of a definition, the SDLC is a structured step-by-step
approach for developing information systems (p. 278).
o
When developing a system, there are three primary choices you will make very
early in the process (p. 279):

Insourcing is how much will be done by your own IT specialists.

Selfsourcing is how much can be done by the end-users.

Outsourcing is how much will be done by a third-party outside the
organization.
o
The SDLC has seven phases:
1) Planning
2) Analysis
3) Design
4) Development

5) Testing
6) Implementation
7) Maintenance
Phase 1: Planning:
o
The planning phase of the SDLC involves determining a solid plan for
developing your information system (p. 279).
o
A project manager is an individual who is an expert in project planning and
management, defines and develops the project plan, and tracks the plan to ensure
all key project milestones are completed on time (p. 280).
o
Three primary activities:

Define the system to be developed.

Identify and select the system for development or determine
which system is required to support the strategic goals of your
organization.

Critical success factors (CSF) are factors critical to your
organization’s success.

Set the project scope.

The project scope clearly defines the high-level system
requirements and is the most basic definition of the system.

A project scope document is a written definition of the project
scope and is usually no longer than a paragraph.

Define the project plan.

The project plan defines the what, when, and who questions of
systems development activities including all activities to be
performed, the individuals, or resources, who will perform the
activities, and the time required to complete each activity (p.
279).

Project milestones represent key dates by which you need a
certain group of activities performed (p. 280).

Phase 2: Analysis:
o
The analysis phase of the SDLC involves end users and IT specialists working
together to gather, understand, and document the business requirements for the
proposed system (p. 281.
o
The primary activity of this phase is to gather business requirements. Business
requirements are the detailed set of knowledge worker requests that the system
must meet to be successful (p. 281).
o
One task to gather business requirements is to perform a joint application
development (JAD) session, knowledge workers and IT specialists meet to define
and review business requirements (p. 281).
o
Once all the business requirements are defined, the end-users sign off on them
indicating that they approve of all the business requirements (p. 281).
o
One of the keys to success in the analysis phase is to find errors in the business
requirements and the project plan. Errors are much cheaper to fix here than later
in the SDLC as indicated by Figure 6.4, p. 282 (p. 282).

Phase 3: Design:
o
The primary goal of the design phase is to build a technical blueprint of how the
proposed system will work. Your point of view changes from a business
perspective to a technical or physical perspective (p. 282).
o
The technical architecture defines the hardware, software, and
telecommunications equipment to run the system (p. 282).
o
Modeling is the activity of drawing a graphical representation of the design (p.
283).

Phase 4: Development:
o
During the development phase of the SDLC, you take all your detailed design
documents from the design phase and transform them into an actual system (p.
283).
o
In this phase, you build your technical architecture by buying and setting up the
technical architecture during the design phase (p. 283).
o
Secondly, you create databases and write any necessary software programs (p.
283).
o
Computer technology advances very rapidly. Sometimes, systems can take
several months to develop and the available technologies may change often (p.
284.

Phase 5: Testing:
o
The testing phase of the SDLC verifies that the system works and meets all the
business requirements defined in the analysis phase (p. 284).
o
First, you develop detailed test conditions, which are the detailed steps the
system must perform along with the expected results of each step (p. 285).

o
Secondly, you actually perform the test (p. 285).
o
It is important that you do not skip any steps (p. 286).
Phase 6: Implementation:
o
During the implementation phase of the SDLC, you distribute the system to all
the knowledge workers and they begin using the system to perform their
everyday jobs (p. 286).
o
First, you will provide user documentation to the knowledge workers which
explain how to use the system (p. 286).
o
Secondly, provide training for the knowledge workers. You must ensure that all
of the knowledge workers have the required training to use the system correctly
(p. 286).
o
Methods of Implementation:

Parallel implementation – using both the old and new system until you
are sure that the new system performs correctly.

Plunge implementation – discarding the old system completely and using
the new system

Pilot implementation – having only a small group of people use the new
system until you know it works correctly, and then adding the remaining
people to the system.

Phased implementation – implementing the new system one part at a
time.

Phase 7: Maintenance:
o
During the maintenance phase of the SDLC, you monitor and support the new
system to ensure it continues to meet the business goals (p. 287).
o
First, you will need to create a help desk to answer your worker’s questions
(p.287).
o
Secondly, you will need to change the system as your business changes (p. 287).