Difference between V-model and Spiral model

1. V-mode :
V-model is the most important model that is used in the process of software testing. It is also known as Verification and Validation Model. It is Introduced by the late Paul Rook in 1980s. V-model is a sequential process in which the next phase begins only after the completion of the present phase. In this model, steps don’t move in a linear way while the steps are bent upwards.

2. Spiral Model :
Spiral Model is a software development life cycle model which is highly used for risk driven models. Based on the risk patterns of a given project, the spiral model helps developers to increase the efficiency of model as most risk already handled. It consist of number of loops which are forming a spiral shape where each loop is called phase of software development cycle.

Difference between V-model and Spiral model :

S.No.	V MODEL	SPIRAL MODEL
1.	V model is software development model but development and testing are not concurrent.	Spiral model is a software development model and is made with features of incremental, waterfall or evolutionary prototyping models.
2.	In V-model testing activities start with the first stage.	Testing is done in spiral model at the end of the engineering phase.
3.	Cost of V-model is expensive.	While cost of spiral model is also very expensive.
4.	Flexibility of V-model is Little flexible.	Flexibility to change in spiral model is not that difficult.
5.	Guarantee of success through V-model is high.	Guarantee of success through Spiral model is low.
6.	User involvement in V-model is also only in beginning.	In this user Involvement is only at the beginning.
7.	It is not iterative.	It is iterative.