software verification and validation ieee software life cycle sqa software quality assurance ieee 730 scm software configuration management ieee 828 std software test documentation ieee 829 srs software requirements specification ieee 830 vv software verification and validation ieee 1012 sdd software design description ieee 1016 spm software project management ieee 1058 sud software user documentation ieee 1063 vte in software project management software testing and software engineering verification and validation vv is the process of checking that a software system meets specifications and that it fulfills its intended purpose it may also be referred to as software quality control it is normally the responsibility of software testers as part of the software development lifecycle in simple terms software verification is assuming we should build x does our software achieve its goals without any bugs or gaps on the other hand software validation is was x what we should have built does x meet the high level requirements definitions verification and validation are not the same thing although they are often confused boehm succinctly expressed the difference as validation are we building the right product verification are we building the product right building the right product implies creating a requirements specification that contains the needs and goals of the stakeholders of the software product if such artifact is incomplete or wrong the developers will not be able to build the product the stakeholders want this is a form of artifact or specification validation building the product right implies the use of the requirements specification as input for the next phase of the development process the design process the output of which is the design specification then it also implies the use of the design specification to feed the construction process every time the output of a process correctly implements its input specification the software product is one step closer to final verification if the output of a process is incorrect the developers are not building the product the stakeholders want correctly this kind of verification is called artifact or specification verification software validation software validation checks that the software product satisfies or fits the intended use highlevel checking ie the software meets the user requirements not as specification artifacts or as needs of those who will operate the software only but as the needs of all the stakeholders such as users operators administrators managers investors etc there are two ways to perform software validation internal and external during internal software validation it is assumed that the goals of the stakeholders were correctly understood and that they were expressed in the requirement artifacts precise and comprehensively if the software meets the requirement specification it has been internally validated external validation happens when it is performed by asking the stakeholders if the software meets their needs different software development methodologies call for different levels of user and stakeholder involvement and feedback so external validation can be a discrete or a continuous event successful final external validation occurs when all the stakeholders accept the software product and express that it satisfies their needs such final external validation requires the use of an acceptance test which is a dynamic test however it is also possible to perform internal static tests to find out if it meets the requirements specification but that falls into the scope of static verification because the software is not running artifact or specification validation requirements should be validated before the software product as whole is ready the waterfall development process requires them to be perfectly defined before design starts but iterative development processes do not require this to be so and allow their continual improvement examples of artifact validation user requirements specification validation user requirements as stated in a document called user requirements specification are validated by checking if they indeed represent the will and goals of the stakeholders this can be done by interviewing them and asking them directly static testing or even by releasing prototypes and having the users and stakeholders to assess them dynamic testing user input validation user input gathered by any peripheral such as keyboard biometric sensor etc is validated by checking if the input provided by the software operators or users meet the domain rules and constraints such as data type range and format software verification it would imply to verify if the specifications are met by running the software but this is not possible e g how can anyone know if the architecturedesignetc are correctly implemented by running the software only by reviewing its associated artifacts someone can conclude if the specifications are met artifact or specification verification the output of each software development process stage can also be subject to verification when checked against its input specification see the definition by cmmi below examples of artifact verification of the design specification against the requirement specification do the architectural design detailed design and database logical model specifications correctly implement the functional and nonfunctional requirement specifications of the construction artifacts against the design specification do the source code user interfaces and database physical model correctly implement the design specification validation vs verification according to the capability maturity model cmmisw v11 software validation the process of evaluating software during or at the end of the development process to determine whether it satisfies specified requirements software verification the process of evaluating software to determine whether the products of a given development phase satisfy the conditions imposed at the start of that phase validation during the software development process can be seen as a form of user requirements specification validation and that at the end of the development process is equivalent to internal andor external software validation verification from cmmis point of view is evidently of the artifact kind in other words software verification ensures that the output of each phase of the software development process effectively carry out what its corresponding input artifact specifies requirement design software product while software validation ensures that the software product meets the needs of all the stakeholders therefore the requirement specification was correctly and accurately expressed in the first place software verification ensures that you built it right and confirms that the product as provided fulfills the plans of the developers software validation ensures that you built the right thing and confirms that the product as provided fulfills the intended use and goals of the stakeholders this article has used the strict or narrow definition of verification from testing perspective fault wrong or missing function in the code failure the manifestation of a fault during execution the software was not effective it does not do what it is supposed to do malfunction according to its specification the system does not meet its specified functionality the software was not efficient it took too many resources such as cpu cycles it used too much memory performed too many io operations etc it was not usable it was not reliable etc it does not do something how it is supposed to do it related concepts both verification and validation are related to the concepts of quality and of software quality assurance by themselves verification and validation do not guarantee software quality planning traceability configuration management and other aspects of software engineering are required within the modeling and simulation ms community the definitions of verification validation and accreditation are similar ms verification is the process of determining that a computer model simulation or federation of models and simulations implementations and their associated data accurately represent the developers conceptual description and specifications ms validation is the process of determining the degree to which a model simulation or federation of models and simulations and their associated data are accurate representations of the real world from the perspective of the intended uses accreditation is the formal certification that a model or simulation is acceptable to be used for a specific purpose the definition of ms validation focuses on the accuracy with which the ms represents the realworld intended uses determining the degree of ms accuracy is required because all ms are approximations of reality and it is usually critical to determine if the degree of approximation is acceptable for the intended uses this stands in contrast to software validation classification of methods in missioncritical software systems where flawless performance is absolutely necessary formal methods may be used to ensure the correct operation of a system test cases test case a test case is a tool used in the process test cases may be prepared for software verification and software validation to determine if the product was built according to the requirements of the user other methods such as reviews may be used early in the life cycle to provide for software validation independent verification and validation isvv stands for independent software verification and validation isvv is targeted at safetycritical software systems and aims to increase the quality of software products thereby reducing risks and costs through the operational life of the software isvv provides assurance that software performs to the specified level of confidence and within its designed parameters and defined requirements isvv activities are performed by independent engineering teams not involved in the software development process to assess the processes and the resulting products the isvv team independency is performed at three different levels financial managerial and technical isvv goes far beyond traditional verification and validation techniques applied by development teams while the latter aim to ensure that the software performs well against the nominal requirements isvv is focused on nonfunctional requirements such as robustness and reliability and on conditions that can lead the software to fail isvv results and findings are fed back to the development teams for correction and improvement isvv history isvv derives from the application of ivv independent verification and validation to the software early isvv application as known today dates back to the early 1970s when the us army sponsored the first significant program related to ivv for the safeguard antiballistic missile system by the end of the 1970s ivv was rapidly becoming popular the constant increase in complexity size and importance of the software lead to an increasing demand on ivv applied to software isvv meanwhile ivv and isvv for software systems gets consolidated and is now widely used by organisations such as the dod faa nasa initially in 20042005 a european consortium led by the european space agency and composed by dnvn etc in 2008 the european space agency released a second version being softwcare sl was the supporting editor having received inputs from many different european space isvv stakeholders this guide covers the methodologies applicable to all the software engineering phases in what concerns isvv isvv methodology isvv is usually composed by five principal phases these phases can be executed sequentially or as results of a tailoring process isvv planning planning of isvv activities system criticality analysis identification of critical components through a set of rams activities value for money selection of the appropriate methods and tools requirements verification verification for completeness correctness testability design verification design adequacy and conformance to software requirements and interfaces internal and external consistency verification of feasibility and maintenance code verification verification for completeness correctness consistency code metrics analysis coding standards compliance verification validation identification of unstable componentsfunctionalities validation focused on errorhandling complementary not concurrent validation regarding the one performed by the development team more for the money more for the time compliance with software and system requirements black box testing and white box testing techniques experience based techniques regulatory environment verification and validation must meet the compliance requirements of law regulated industries which is often guided by government agencies software testing portal compiler correctness crossvalidation formal verification functional specification independent verification and validation facility international software testing qualifications board software verification software requirements specification validation drug manufacture verification and validation general verification and validation of computer simulation models independent verification systems software testing software engineering software quality static code analysis notes and references 10122012 ieee standard for system and software verification and validation 2012 doi101109ieeestd20126204026 isbn9780738172682 tran e 1999 verificationvalidationcertification in koopman p topics in dependable embedded systems carnegie mellon university retrieved 20070518 menzies t y hu 2003 data mining for very busy people computer 36 1 2229 doi101109mc20031244531 chapter on software quality including vnv in swebok vtesoftware engineeringfields computer programming requirements engineering software deployment software design software maintenance software testing systems analysis formal methods concepts data modeling enterprise architecture functional specification modeling language orthogonality programming paradigm software software archaeology software architecture software configuration management software development methodology software development process software quality software quality assurance software verification and validation structured analysis orientations agile aspectoriented object orientation ontology service orientation sdlc modelsdevelopmental agile eup executable uml incremental model iterative model prototype model rad up scrum spiral model vmodel waterfall model xp other spice cmmi data model er model function model information model metamodeling object model systems model view model languages idef uml usl sysml softwareengineers victor basili kent beck grady booch fred brooks barry boehm peter chen danese cooper ward cunningham tom demarco edsger w dijkstra delores m etter martin fowler adele goldstine margaret hamilton c a r hoare lois haibt mary jean harrold grace hopper watts humphrey michael a jackson ivar jacobson alan kay nancy leveson stephen j mellor bertrand meyer david parnas trygve reenskaug winston w royce james rumbaugh mary shaw peri tarr elaine weyuker niklaus wirth edward yourdon related fields computer science computer engineering project management risk management systems engineering category commons 