Verification and Validation Concepts

Verification Concepts “A Verification concept is the understanding of principles, rationale, rules, participant roles and the psychologies of various techniques used to evaluate systems during development.”

Validation Concepts “Validation typically involves actual testing and takes place after verifications are completed.”

Verification Techniques Audits • An independent assessment of a project • To verify whether or not the project is in compliance with appropriate policies, procedures, standards, contractual specifications • An audit may include operational aspects of the project Reviews and Inspections • To determine whether or not to continue development To identify defects in the product early in the life cycle

Types of Reviews 1. In-Process Reviews 2. Milestone Reviews (also called) Decision-point/Phase-end Reviews (a) Test Readiness Review (b)Test Completion Review 3. Post Implementation Reviews (also called) Post Mortem

Types of Review 1. In-Process •Assess progress towards requirements • During a specific period of the development cycle – like design period • Limited to a segment of the product • Used to find defects in the work product and the work process • Catches defects early – where they are less costly to correct.

2. Decision-point & Phase-end •Review of products and processes near the completion of each phase of development •Decisions for proceeding with development are based on cost, schedule, risk, progress, readiness for next phase •Also referred to as Milestone Review •Contains Requirements, Critical Design, Test Readiness and Phase-end Reviews

Decision-point & Phase-end Software Requirements Review •Requirements documented •Baseline established •Analysis areas identified •Software development plan •Test plan •Configuration management plan derived

Critical Design Review •Baselines the detailed design specification •Test cases are reviewed and approved •Usually, coding will begin at the close of this phase.

Test Readiness Reviews • Performed when the appropriate modules are near completion • Determines whether or not testing should progress based on a review of entrance and exit criteria • Determines the readiness of the application/project for system and acceptance testing

Test Completion Reviews • Determine the state of the software product

3.Post Implementation Reviews •Also known as “Postmortems”

• Review/evaluation of the product that includes planned vs. actual development results and compliance with requirements •Used for process improvement of software development •Can be held up to three to six months after implementation

•Conducted in a formal format

Classes of Reviews 1. Informal Review 2. Semiformal Review 3. Formal Review

Informal • Also called peer-reviews • Generally one-on-one meeting between author of a work product & Peer.

• Initiated as a request for input • No agenda • Results are not formally reported • Occur as needed through out each phase

Semiformal •Facilitated by the author •Presentation is made with comment at the end •Presentation is made with comment made throughout •Issues raised are captured and published in a report distributed to participants •Possible solutions for defects not discussed •Occur one or more times during a phase

Formal •Facilitated by a moderator (not author) •Moderator is assisted by a recorder •Defects are recorded and assigned •Meeting is planned •Materials are distributed beforehand •Participants are prepared- their preparedness dictates the effectiveness of the review •Full participation by all members of the reviewing team is required •A formal report captures issues raised and is distributed to participants and management •Defects found are tracked through the defect tracking system and followed through to resolution •Formal reviews may be held at any time

Review Rules 1.The product is reviewed, not the producer 2.Defects and issues are identified, not corrected 3. All members of the reviewing team are responsible for the results of the review

Review Notes # “Stage Containment”: identifying defects in the stage in which they were created, rather than in later testing stages. # Reviews are generally greater than 65% effective Testing is often less than 30% effective # The earlier defects are found the less expensive they are to correct In addition to learning about a specific product/project, team members are exposed to a variety of approaches to technical issues,Provides training in and enforces the use of standards.

Participant Roles Management of V & V 1. Prepare the plans for execution of the process 2. Initiate the implementation of the plan 3. Monitor the execution of the plan 4. Analyze problems discovered during the execution of the plan 5. Report progress of the processes 6. Ensure products satisfy requirements 7. Assess evaluation results 8. Determine whether a task is complete 9. Check the results for completeness