If a Software was developed depends on specific
customer requirement then that software was
called as Software project.
If a software was developed by company
depends on overall requirements in the market
called as Software product.
Software Development Life Cycle is a process to
develop a new software.
OLD SDLC Models
1. Waterfall Model
2. Prototype Model
4. Spiral Model
5.RAD(Rapid Application Development) Model
When customer requirements are
clear, organization can fallow waterfall model.
This is also called as Liner sequential model.
Because one step start with after completion
Waterfall model is the earliest SDLC approach
that was used for software development.
Waterfall model start with software Bidding
means that a proposal to develop a new
1.Waterfall model is a easy model to Implement
any size of project.
2.Waterfall model is sequential model due to this
reason testing should run on every module.
3. This model causes low business cost because
this model helps to find problems earlier, after
finds problems is fixing complex and costly.
4. In this model documented every stage allowing
people to understand easily.
1. In waterfall model any requirement will change
in the middle of the process this model can not
2. In this model only one stage of testing is there
that to conducted by developers.
3. This model is taking more time because of it is a
sequential model, one step will be staring after
completion previous step, so we want to wait up
to completion of previous step.
When customer requirements are not clear
then many organizations are following this
In prototype model when customer
requirements are not clear that time Business
Analyst(BA) can prepare prototype screens
based on previous projects knowledge and
showing customer site people to get clear
The process flow of Prototype model also same
as Waterfall model but in requirement gathering
stage added one extra step as shown below
Kick of Meeting
To get clear
Prototype model method is employed when very
difficult to get exact requirements from the customer
that time we are using this model.
In the above diagram requirement stage Business
Analyst(BA) can prepare Prototype screens and
showing to customer site people to get clear
1. When prototype is shown to customer, he gets a
proper clarity on requirements and he can suggest the
modifications if needed.
2. Customers usually not good at specifying their
requirements , or can tell not properly what they
expect from software that time this is useful.
1. Prototype model also having one stage of testing and
that to conducted by developers.
2. Too many changes can disturb the software
3. To much investment of client, is not always preferred
by the developer.
In incremental model multiple development stages
takes place here. Cycles are divided into smaller and
more easily managed iterations.
When customer requirements are huge organizations
are follows incremental model to develop a new
Here software development will be done installment
Here huge requirements are dividing into small
requirements and developing the software installment by
When customer having huge requirement and needs
quick delivery that time organizations are using
This model allowing customer to change requirements
and scope modification.
Generating working software quickly.
Easy to manage iterations.
This model was developed by Berry Boehm.
When customer requirements are enhancing regularly
the organizations are following Spiral model.
Here customer requirements changing regularly at the
time development process.
This model is also incremental development process,
here customer given the requirements based on
satisfaction of the previous stage development process.
• Spiral model is a combination of iteration development
model process and linear sequential model.
• In Spiral model the total software is spitted into sprints.
• Spiral model develops the software module by module
or sprint by sprint.
• It is allowing customer to change their requirements at
any stage of development.
• Customer site people with get the software as early as
possible if they need because software will develop
module by module.
It complex to use for small and low risk projects.
Large number of stages will require to complete the
software, documentation will be complex.
When customer requirements are similar to previous or
old projects then organizations are following this RAD
This model needs minimal planning to develop this
type of software's.
To develop new software by coping the code from old
projects or products.
The above 5 SDLC models are having a single stage of
testing and that to conducted by developers. Due to
this reason organizations are going to use Advanced
SDLC models to release a quality software to customer.
This model define mapping in between multiple stages
of development and multiple stages of Testing.
Fish model is using where manufacturing will take
more loss organizations are using Fish model.
Ex: Racket launching.
In Fish model every stage of testing is there.
In fish model Software testing stage will be continued
with respect to software development stage.
Here BRS, SRS, Design documents verification will be
done by authors means that who prepared that
documents that people can responsible to review the
Here Business Analyst can gathering the requirements
and can prepare the BRS.
Here System Analyst can study the BRS and can
prepare the SRS.
Technical Architect can prepare the HLD and LLds
Here developers can write code with respect to LLD’s
and done unit testing and integration testing.
After software coding A separate testing team will test
Customer site people will responsible for acceptance
Fish model is time consuming model and costly model
This model defines mapping in between software
testing stages and software development stages.
V-model stands verification and validation.
Verification will done with respect to customer
requirements and validation will done with respect to
Here coding will done with respect to low level design
and conducting Unit testing.
Integrating the unit tested programs and conducted
integration testing with respect to HLD.
Here software testing will done with respect to SRS
prepared by System Analyst.
Acceptance testing will done with respect to BRS
prepared by Business Analyst.
In acceptance testing customer site people can involve
and give feedback on software with respect to BRS
called as acceptance testing.
The testing activity is perform in the each phase of
Software Testing Life Cycle phase.
V-model shows software development stage in left side
and software testing stage in right side.
From above V-Model separate testing team is available
for software testing stage only, Because software
testing is bottle neck stage of development.
Agile model stands for developers develop the
deliverables and tester can test those deliverables at the
same time stakeholders can accept those deliverables.
In Agile model after accepting the deliverable only
start the next stage of testing.
In Agile model the software is developing module by
module. Means that once completion of one module ,
that module can be delivered to customer for
acceptance, if they accept that then start the next
When customer requirements are not clear,Small
and medium scale organizations are try to follow this
Prototype V-model and large scale companies are
following Prototype-Agile model, this is also called as
Agile Extreme model.
when customer requirements are huge small and
medium scale companies are try to follow Incremental
V-model and large scale companies are following
Incremental- Agile model this is also called as Agile
When customer requirements are Enhancing regularly
small and medium scale companies are following
Spiral-V-model and large scale companies are
following Spiral – Agile model also called as Agile
In Agile scrum model the software is divided into
sprints and developing the software sprint by sprint is
called as Agile Scrum.