verification and validation

Software Independent Verification and Validation(IV&V)NASA IV&V FacilityFairmont, West VirginiaJudith N. BrunerActing Director304-367-8202judith.n.bruner.1@gsfc.nasa.gov : 

<![CDATA[ Software Independent Verification and Validation (IV&V) NASA IV&V Facility Fairmont, West Virginia Judith N. Bruner Acting Director 304-367-8202 judith.n.bruner.1@gsfc.nasa.gov ]]>

Content: 

<![CDATA[ Content Why are we discussing IV&V? What is IV&V? How is IV&V done? IV&V process Why perform IV&V? Summary Points of Contact]]>

Why are we discussing IV&V?: 

<![CDATA[ Why are we discussing IV&V? ]]>

Setting the Stage: 

<![CDATA[ Setting the Stage In the 90s, the Commanding General of theArmy’s Operational Test and Evaluation Agency noted that 90 percent of systems that were not ready for scheduled operational tests had been delayed by immature software.]]>

Slide5: 

<![CDATA[ Software “Chaos” 16% Successful - In Budget - On Time - Meets Requirements - User involved 31% Cancelled - Development 53% “Challenged” - Over budget by 189% - Late by 222% - Missing 39% of Capabilities Note: For Large Companies - 9% were Successful - 61.5% Challenged - Over budget by 178% - Late by 230% - Missing 58% of Capabilities - 29.5% were Cancelled The Standish Group examined 8,380 Software Projects.]]>

Error Densities: 

<![CDATA[ Error Densities 68% 9% 23% Requirements Specification Installation & Commissioning Design & Implementation]]>

Increasing Cost of Changes: 

<![CDATA[ Increasing Cost of Changes (Normalized to Requirements Phase) The cost to correct an software error multiplies during the development lifecycle. Cost scale factor]]>

What is IV&V?: 

<![CDATA[ What is IV&V? ]]>

Independent Verification and Validation (IV&V): 

<![CDATA[ Independent Verification and Validation (IV&V) Independent Technical: IV&V prioritizes its own efforts Managerial: Independent reporting route to Program Management Financial: Budget is allocated by program and controlled at high level such that IV&V effectiveness is not compromised Verification (Are we building the product right?) The process of determining whether or not the products of a given phase of the software development cycle fulfill the requirements established during the previous phase Is internally complete, consistent and correct enough to support next phase Validation (Are we building the right product?) The process of evaluating software throughout its development process to ensure compliance with software requirements. This process ensures: Expected behavior when subjected to anticipated events No unexpected behavior when subjected to unanticipated events System performs to the customer’s expectations under all operational conditions]]>

Independent Verification & Validation: 

<![CDATA[ Independent Verification & Validation Software IV&V is a systems engineering process employing rigorous methodologies for evaluating the correctness and quality of the software product throughout the software life cycle Adapted to characteristics of the target program ]]>

How is IV&V done?: 

<![CDATA[ How is IV&V done? ]]>

IV&V Activities Throughout Lifecycle: 

<![CDATA[ IV&V Activities Throughout Lifecycle ]]>

IV&V Life Cycle Functions: 

<![CDATA[ IV&V Life Cycle Functions IV&V Process provides tools and analysis procedures appropriate to each phase of the software development life cycle: Formulation Phase: Is development process sound, repeatable, and managed? Requirements Phase: Verify that system and software requirements are correct, complete, traceable and testable Analyze system-level requirements: Are test plans and acceptance criteria sufficient to validate system requirements and operational needs? Are testing methods sufficient to verify and validate software requirements? Are the correct software development, management, and support processes in place? Design Phase: Does the design support the requirements? Are test plans and test environments sufficient to verify and validate software and operational requirements? Does the design have any characteristics that will cause it to fail under operational scenarios? What solutions are appropriate? ]]>

IV&V Life Cycle Functions (cont.): 

<![CDATA[ IV&V Life Cycle Functions (cont.) Typical IV&V functions by Software life-cycle phase (cont.): Coding Phase: Does the code reflect the design? Is the code correct? Verify that test cases trace to and cover software requirements and operational needs Verify that software test cases, expected results, and evaluation criteria fully meet testing objectives Analyze selected code unit test plans and results to verify full coverage of logic paths, range of input conditions, error handling, etc. Test Phase: Analyze correct dispositioning of software test anomalies Validate software test results versus acceptance criteria Verify tracing and successful completion of all software test objectives Operational Phase: Verify that regression tests are sufficient to identify adverse impacts of changes]]>

IV&V Testing Involvement: 

<![CDATA[ IV&V Testing Involvement IV&V identifies deficiencies in program’s test planning Program changes their procedures to address deficiencies vice IV&V independently test IV&V may independently test highly critical software using an IV&V testbed Whitebox Stress Endurance Limit Developer motivated to show software works IV&V attempts to break software]]>

IV&V Process: 

<![CDATA[ IV&V Process ]]>

IV&V Process : 

<![CDATA[ IV&V Process Integrates IV&V into program Provides IV&V funding Resolves Exception issues Reflects IV&V in program mgmt plan Agrees to data transfer plan Reflects agreement in subcontracts IV&V in phase with development ]]>

IV&V Scope: 

<![CDATA[ IV&V Scope Scope is determined so as to minimize the risk within the Program’s IV&V budget. Effort is based on: Criticality and risk of system functions performed/managed by software Budget limitations Program’s IV&V budget]]>

CARA Scoring Methodology: 

<![CDATA[ CARA Scoring Methodology]]>

CARA Criticality: 

<![CDATA[ CARA Criticality Sample Criticality Evaluation Criteria]]>

CARA Risk: 

<![CDATA[ CARA Risk Sample Risk Driver Criteria]]>

Requirements Analysis IALs: 

<![CDATA[ Requirements Analysis IALs]]>

Design Analysis IALs: 

<![CDATA[ Design Analysis IALs]]>

Code Analysis IALs: 

<![CDATA[ Code Analysis IALs]]>

Test Analysis IALs: 

<![CDATA[ Test Analysis IALs]]>

IV&V Is Process As Well As Product Oriented: 

<![CDATA[ IV&V Is Process As Well As Product Oriented]]>

IV&V Increases Program Awareness: 

<![CDATA[ IV&V Increases Program Awareness]]>

Staffing Paradigm: 

<![CDATA[ Staffing Paradigm]]>

Why perform IV&V?: 

<![CDATA[ Why perform IV&V? ]]>

IV&V Benefits: 

<![CDATA[ IV&V Benefits Technical Management]]>

Summary: 

<![CDATA[ Summary ]]>

IV&V Key Points: 

<![CDATA[ IV&V Key Points IV&V works with the Project Goal is project success IV&V is an engineering discipline IV&V processes are defined and tailored to the specific program Mission, operations and systems knowledge is used to perform engineering analyses of system components IV&V is most effective when started early 70% of errors found in testing are traceable to problems in the requirements and design IV&V works problems at the lowest possible level Primarily work via established informal interfaces with the development organization - working groups, IPTs, etc. Elevate issues only when necessary]]>

IV&V Approach Efficiently Mitigates Risk: 

<![CDATA[ IV&V Approach Efficiently Mitigates Risk It is not necessary or feasible to perform all IV&V analyses on all software functions IV&V resources allocated to reduce overall exposure to operational, development, and cost/schedule risks Software functions with higher cirticality and development risk receive enhanced levels of analysis (‘CARA’ process) Systems analyses performed to reduce costly interface and integration problems Process analyses performed to verify ability to produce desired result relative to program plans, needs and goals IV&V working interfaces promote timely problem resolution Proactive participation on pertinent development teams Emphasis on early identification of technical problems Engineering recommendations provided to expedite solution development and implementation]]>

Analyses Are Value Added and Complementary- Not Duplicative: 

<![CDATA[ Analyses Are Value Added and Complementary - Not Duplicative Analyses performed from a systems perspective considering mission needs and system use, hazards and interfaces Discipline experts assigned to perform analysis across all life cycle phases Horizontal specialty skills are matrixed across IV&V functional teams to verify correct systems integration Specialized tools and simulations perform complex analyses IV&V testing activities complement developer testing enhancing overall software confidence Developer testing focuses on demonstrating nominal behavior, IV&V testing activities try to break the software Overall program integration, test and verification approach analyzed for completeness, integrity and effectiveness]]>

Why use NASA IV&V Facility?: 

<![CDATA[ Why use NASA IV&V Facility? Software IV&V, as practiced by the NASA Software IV&V Facility, is a well-defined, proven, systems engineering discipline designed to reduce the risk in major software developments.]]>

NASA IV&V FacilityPoints of Contact: 

<![CDATA[ NASA IV&V Facility Points of Contact Judy Bruner Acting Director 304-367-8202 judith.n.bruner.1@gsfc.nasa.gov Bill Jackson Deputy Director 304-367-8215 bill.jackson@ivv.nasa.gov ]]>