CHAPTER 9
Diagrammatic Representation of V Model:
In Brief:
There are two phases in the V model development. They are
1. Verification
2. Validation.
Verification Phases
Requirements analysis
In this phase, the requirements of the proposed system are collected by analyzing the needs of the user(s). This phase is concerned about establishing what the ideal system has to perform. However, it does not determine how the software will be designed or built. Usually, the users are interviewed and a document called the user requirements document is generated. The user requirements document will typically describe the system’s functional, physical, interface,
performance, data, security requirements etc as expected by the user.The users carefully review this document as this document would serve as the guideline for the system designers in the system design phase. The user acceptance tests(UAT) are designed in this phase.
System Design
System engineers analyze and understand the business of the proposed system by studying the user requirements document. They figure out possibilities and techniques by which the user requirements can be implemented. If any of the requirements is not feasible, the user is informed of the issue. A resolution is found and the user requirement document is edited accordingly.The software specification document which serves as a blueprint for the development phase is generated. This document contains the general system organization, menu structures, data structures etc. It may also hold examples business scenarios, sample windows, reports for the better understanding. Other technical documentation like entity diagrams, data dictionary will also be produced in this phase. The documents for system testing is prepared in this phase.
Architecture Design
This phase can also be called as high-level design (HLD). The baseline in selecting the architecture is that it should realize all the requirements within the given time, cost and resources. Software architecture is commonly represented as two-tier, three-tier or multi-tier models which typically comprises of the database layer, user-interface layer and the application layer. The modules and components representing each layer, their inter-relationships, subsystems, operating environment and interfaces are laid out in detail.The output of this phase is the high-level design document which typically consists of the list of modules, brief functionality of each module, their interface relationships, dependencies, database tables, architecture diagrams, technology details etc. The integration testing design is carried
out in this phase.
Module Design
This phase can also be called as low-level design (LLD). The designed system is broken up in to smaller units or modules and each of them is explained so that the programmer can start coding directly. The low level design document or program specifications will contain a detailed functional logic of the module, in pseudocode - database tables, with all elements, including their type and size - all interface details with complete API references- all dependency issues- error
message listings- complete input and outputs for a module. The unit test design is developed in this stage.
Coding
It is the process of writing, testing, and maintaining the source code of computer programs. The source code is written in a programming language.
Validation Phases
Unit Testing
In the V-model of software development, unit testing implies the first stage of dynamic testing process.It involves analysis of the written code with the intention of eliminating errors. It also verifies that the codes are efficient and adheres to the adopted coding standards. Testing is usually white box. It is done using the Unit test design prepared during the module design phase. This may be carried out by software testers, software developers or both.
Integration Testing
In integration testing the separate modules will be tested together expose faults in the interfaces and in the interaction between integrated components. Testing is usually black box as the code is not directly checked for errors. It is done using the integration test design prepared during the architecture design phase. Integration testing is generally conducted by software testers.
System Testing
System testing will compare the system specifications against the actual system. The system test design derived from the system design documents and is used in this phase. Sometimes system testing is automated using testing tools. once all the modules are integrated several erros may rise.Testing done at this stage is called system test.
User Acceptance Testing
Acceptance Testing checks the system against the requirements of the user. It uses black box testing using real data, real people and real documents to ensure ease of use and functionality of systems. Users who understand the business functions run the tests as given in the acceptance test plans, including installation and Online help. Hardcopies of user documentation are also being reviewed for usability and accuracy. The testers formally document the results of each test, and provide error reports, correction requests to the developers.
Diagrammatic Representation of V Model:
In Brief:
There are two phases in the V model development. They are
1. Verification
2. Validation.
Verification Phases
Requirements analysis
In this phase, the requirements of the proposed system are collected by analyzing the needs of the user(s). This phase is concerned about establishing what the ideal system has to perform. However, it does not determine how the software will be designed or built. Usually, the users are interviewed and a document called the user requirements document is generated. The user requirements document will typically describe the system’s functional, physical, interface,
performance, data, security requirements etc as expected by the user.The users carefully review this document as this document would serve as the guideline for the system designers in the system design phase. The user acceptance tests(UAT) are designed in this phase.
System Design
System engineers analyze and understand the business of the proposed system by studying the user requirements document. They figure out possibilities and techniques by which the user requirements can be implemented. If any of the requirements is not feasible, the user is informed of the issue. A resolution is found and the user requirement document is edited accordingly.The software specification document which serves as a blueprint for the development phase is generated. This document contains the general system organization, menu structures, data structures etc. It may also hold examples business scenarios, sample windows, reports for the better understanding. Other technical documentation like entity diagrams, data dictionary will also be produced in this phase. The documents for system testing is prepared in this phase.
Architecture Design
This phase can also be called as high-level design (HLD). The baseline in selecting the architecture is that it should realize all the requirements within the given time, cost and resources. Software architecture is commonly represented as two-tier, three-tier or multi-tier models which typically comprises of the database layer, user-interface layer and the application layer. The modules and components representing each layer, their inter-relationships, subsystems, operating environment and interfaces are laid out in detail.The output of this phase is the high-level design document which typically consists of the list of modules, brief functionality of each module, their interface relationships, dependencies, database tables, architecture diagrams, technology details etc. The integration testing design is carried
out in this phase.
Module Design
This phase can also be called as low-level design (LLD). The designed system is broken up in to smaller units or modules and each of them is explained so that the programmer can start coding directly. The low level design document or program specifications will contain a detailed functional logic of the module, in pseudocode - database tables, with all elements, including their type and size - all interface details with complete API references- all dependency issues- error
message listings- complete input and outputs for a module. The unit test design is developed in this stage.
Coding
It is the process of writing, testing, and maintaining the source code of computer programs. The source code is written in a programming language.
Validation Phases
Unit Testing
In the V-model of software development, unit testing implies the first stage of dynamic testing process.It involves analysis of the written code with the intention of eliminating errors. It also verifies that the codes are efficient and adheres to the adopted coding standards. Testing is usually white box. It is done using the Unit test design prepared during the module design phase. This may be carried out by software testers, software developers or both.
Integration Testing
In integration testing the separate modules will be tested together expose faults in the interfaces and in the interaction between integrated components. Testing is usually black box as the code is not directly checked for errors. It is done using the integration test design prepared during the architecture design phase. Integration testing is generally conducted by software testers.
System Testing
System testing will compare the system specifications against the actual system. The system test design derived from the system design documents and is used in this phase. Sometimes system testing is automated using testing tools. once all the modules are integrated several erros may rise.Testing done at this stage is called system test.
User Acceptance Testing
Acceptance Testing checks the system against the requirements of the user. It uses black box testing using real data, real people and real documents to ensure ease of use and functionality of systems. Users who understand the business functions run the tests as given in the acceptance test plans, including installation and Online help. Hardcopies of user documentation are also being reviewed for usability and accuracy. The testers formally document the results of each test, and provide error reports, correction requests to the developers.
3 Responses to “V Model !!!”
hi this is vinod khairnar You have very well explained V model. It is very helpful for me..
Thanks buddyyyyyyy.......
hi this is vinod khairnar You have very well explained V model. It is very helpful for me..
Thanks buddyyyyyyy.......
wonderful post but can u add the explanation of v-model diagram please. In this jst u have described the points but not the working of the diagram.
Thanks a lot for this post.
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