Understanding the Role of V and V in SDLC
1) Traceability Analysis:
It traces each software requirement back to the system requirements established in the concept activity. This is to ensure that each requirement correctly satisfies the system requirements and that no extraneous software requirements are added. In this technique, we also determine whether any derived requirements are consistent with the original objectives, physical laws and the technologies described in system document.
2) Interface Analysis:
It is the detailed examination of the interface requirements specifications. The evaluation criteria is same as that for requirements specification. The main focus is on the interfaces between software, hardware, user and external software.
3) Criticality Analysis:
Criticality is assigned to each software requirement. When requirements are combined into functions, the combined criticality of requirements form the criticality for the aggregate function. Criticality analysis is updated periodically as requirement changes are introduced. This is because such charges can cause an increase or decrease in a functions criticality which depends on how the revised requirement impacts system criticality.
Criticality analysis is a method used to locate and reduce high risk problems and is performed at the beginning of the project. It identifies the functions and modules that are required to implement critical program functions or quality requirements like safety, security etc.
Criticality analysis involves the following steps
Step – 1: Construct a block diagram or control flow diagram (CFD) of the system and its elements. Each block will represent one software function (or module) only.
Step – 2: Trace each critical function or quality requirement through CFD.
Step – 3: Classify all traced software functions as critical to
(a) Proper execution of critical software functions.
(b) Proper execution of critical quality requirements.
Step – 4: Focus additional analysis on these traced critical software functions.
Step – 5: Repeat criticality analysis for each life cycle process to determine whether the implementation details shift the emphasis of the criticality.
4) Hazard and Risk Analysis:
It is done during the requirements definition activity. Now hazards or risks are identified by further refining of the system requirements into detailed software requirements. These risks are assessed for their impact on the system.
Various V & V Activities can be summarized as under:
|V& V Tasks||Main Issues|
|1||# Traceability analysis.
# Software requirements evaluation.
|Evaluates the correctness, completeness, accuracy, consistency, testability and readability of software requirements.|
|2||Interface analysis||Evaluates the software interfaces.|
|3||Criticality analysis||Identifies the criticality of each software function.|
|4||System V&V test plan generation.||Initiates the V&V test planning for V&V system test.|
|5||Acceptance V&V test plan generation.||Initiates the V&V test planning for V&V acceptance test.|
|6||Configuration management assessment.||Ensures completeness and adequacy of SCM process.|
|7||Hazard analysis||Identifies potential hazards, based on the product data during the specified development activity.|
|8||Risk analysis||Identifies potential risks, based on the product data during the specified development activity.|
|1||Traceability analysis.||Evaluates software design modules for correctness, completeness, accuracy, consistency, testability and readability.|
|2||Software design evaluation.||–|
|5||Component V&V test plan generation and verification||Initiates the V&V test planning for V&V component test.|
|6||Integration V&V test plan generation and verification.||Initiates the V&V test planning for V&V integration test.|
|2||Source code and source code documentation evaluation.||Verifies the correctness, completeness, consistency, accuracy, testability and readability of source code.|
|5||V&V test case generation and verification.||–|
|6||V&V test procedure generation and verification.||–|
|7||Component V&V test execution and verification.||–|
|2||Acceptance V&V test procedure generation and verification.||–|
|3||Integration V&V test execution and verification.||–|
|4||System V&V test execution and verification.||–|
|5||Acceptance V&V test execution and verification.||–|
|1||SVVP (Software verification and validation plan) revision.||Modifies the SVVP.|
|2||Proposed change assessment.||–|
|3||Anomaly evaluation.||Evaluates the effect on software of operation anomalies.|
|5||Migration assessment.||Verifies the correctness of software when migrated to a different operational environment.|
|6||Retirement assessment.||Ensures that the existing system continues to function correctly when specific software elements are retired.|