V-Model

[
[http://www.itsdocs.fhwa.dot.gov/jpodocs/repts_te/14158.htm "Clarus Concept of Operations."] Publication No. FHWA-JPO-05-072, Federal Highway Administration (FHWA), 2005] ] The V-Model (or VEE model) is a systems development model designed to simplify the understanding of the complexity associated with developing systems. [cite web | url=http://ops.fhwa.dot.gov/publications/seitsguide/seguide.pdf | title=Systems Engineering for Intelligent Transportation Systems| publisher=US Dept. of Transportation|pages=pp 10| accessdate=2007-06-09] Forsberg, K., Mooz, H., Cotterman, H. "Visualizing Project Management," 3rd edition, John Wiley and Sons, New York, NY, 2005. Pages 108-116, 242-248, 341-360.] International Council On Systems Engineering (INCOSE), "Systems Engineering Handbook Version 3.1," August 2007, pages 3.3 to 3.8] In systems engineering it is used to define a uniform procedure for product of project development.

Overview

The V-model is a graphical representation of the systems development lifecycle. It summarizes the main steps to be taken in conjunction with the corresponding deliverables within computerized system validation framework.

The "VEE" is a process that represents the sequence of steps in a project life cycle development. It describes the activities and results that have to be produced during product. The left side of the "VEE" represents the decomposition of requirements, and creation of system specifications. The right side of the "V" represents integration of parts and their verification. [cite paper| title=System Engineering for Faster, Cheaper, Better| author=Forsberg, K., Mooz, H. | url=http://www.incose.org/sfbac/welcome/fcb-csm.pdf | publisher=Center of Systems Management| year=1998] [cite web| url = http://www.gmu.edu/departments/seor/insert/robot/robot2.html | title = The SE VEE | publisher=SEOR, George Mason University | accessdate=2007-05-26] Forsberg, K. and Mooz, H., " [http://www.csm.com/repository/model/rep/o/pdf/Relationship%20of%20SE%20to%20Proj%20Cycle.pdf The Relationship of Systems Engineering to the Project Cycle] ," First Annual Symposium of the National Council On Systems Engineering (NCOSE), October 1991] V stands for "Verification and Validation"

V Model topics

Systems Engineering and verification

The Systems Engineering Process (SEP) provides a path for improving the cost effectiveness of complex systems as experienced by the system owner over the entire life of the system, from conception to retirement.

It involves early and comprehensive identification of goals, a concept of operations that describes user needs and the operating environment, thorough and testable system requirements, detailed design, implementation, rigorous acceptance testing of the implemented system to ensure it meets the stated requirements (system verification), measuring its effectiveness in addressing goals (system validation), on-going operation and maintenance, system upgrades over time, and eventual retirement.

The process emphasizes requirements-driven design and testing. All design elements and acceptance tests must be traceable to one or more system requirements and every requirement must be addressed by at least one design element and acceptance test. Such rigor ensures nothing is done unnecessarily and everything that is necessary is accomplished.

The specification stream

The specification stream mainly consists of:
* User Requirement Specifications
* Functional Specifications
* Design Specifications

The testing stream generally consists of:
* Installation Qualification (IQ)
* Operational Qualification (OQ)
* Performance Qualification (PQ)

The development stream can consist (depending on the system type and the development scope) in customization, configuration or coding.

Applications

The V-model is used to regulate the software development process within the German federal administration. Nowadays it is still the standard for German federal administration and defence projects, as well as software developers within in the region.

The concept of the V-Model was developed simultaneously, but independently, in Germany and in the United States in the late 1980s. The US V-Model, as documented in the 1991 proceedings for the National Council on Systems Engineering (NCOSE; now INCOSE as of 1995), was developed for satellite systems involving hardware, software, and human interaction. It has now found wide-spread application in commercial as well as defence programs. Its primary use is in and Project Management throughout the project lifecycle.

One fundamental characteristic of the US V-Model is that time and maturity move from left to right and one cannot move back in time. All iteration is along a vertical line to higher or lower levels in the system hierarchy, as shown in the figure. This has proven to be an important aspect of the model. The expansion of the model to a dual-Vee concept is treated in reference .

As the V-model is publicly available many companies also use it. In project management it is a method comparable to PRINCE2 and describes methods for project management as well as methods for system development. The V-Model while rigid in process, can be very flexible in application, especially as it pertains to the scope outside of the realm of the System Development Lifecycle normal parameters.

See also

* RUP (as a supporting software process)
* Systems analysis
* Systems design
* Systems Development Life Cycle
* Dual Vee Model

References

External links

* [http://g2sebok.incose.org/app/qualsys/view_by_id.cfm?ID=INCOSE%20G2SEBOK%203.30&ST=F Vee Model of Systems Engineering Design and Integration]
* [http://www.v-modell.iabg.de/#WASIST What is the V-model?] (in German)
* [ftp://ftp.tu-clausthal.de/pub/institute/informatik/v-modell-xt/Releases/1.2.1/Documentation/V-Modell-XT-Complete.pdf V-Model XT Documentation]
* [http://www.coleyconsulting.co.uk/testtype.htm Types of Testing]
* [http://www.glemser.com/images/misc/VModel.gifImage]
* [http://www.the-software-experts.de/e_dta-sw-process.htm Software Processes (also the V-Modell)]
* [http://www.harmonicss.co.uk/index.php/main-blog/blog-engineering/41-blog-engineering/56-the-death-of-the-v-model?task=view Death of the V-Model] (small software projects but not large systems of systems?)