1 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Supplementary Slides for Software Engineering: A Practitioner's Approach, 5/e Supplementary Slides for Software Engineering: A Practitioner's Approach, 5/e copyright © 1996, 2001 R.S. Pressman & Associates, Inc. For University Use Only May be reproduced ONLY for student use at the university level when used in conjunction with Software Engineering: A Practitioner's Approach. Any other reproduction or use is expressly prohibited. This presentation, slides, or hardcopy may NOT be used for short courses, industry seminars, or consulting purposes.

2 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Chapter 8 Software Quality Assurance

3 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 SQA Encompasses…  A quality management approach  Effective SE technology (methods & tools)  Formal technical reviews  A multi-tiered testing strategy  Compliance with development standard  Measurement & reporting mechanism ++

4 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Why SQA Activities Pay Off? cost to find and fix a defect log scale 1 Req. Design code test system test field use

5 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Quality Concepts  general objective: reduce the “variation between samples”... but how does this apply to software?  quality control: a series of inspections, reviews, tests  quality assurance: analysis, auditing and reporting activities  cost of quality  appraisal costs  failure costs  external failure costs

6 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 What is quality?  A characteristic or attribute of something (American Heritage Dictionary)  Measurable characteristics  such as length, color, electrical properties, & malleability.  Software’s characteristics:  cyclomatic complexity, cohesion, number of function points, LOC, and many others ++

7 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Quality Two kinds of software quality: 1.Quality of design: the characteristics that the designers specify for an item. Eg, requirements, specifications, and design 2.Quality of conformance: the degree to which the design specifications are followed during manufacturing Eg, implementation ++

8 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Quality Control  Involves the series of inspections, reviews, and tests used throughout the software process to ensure each work product meets the requirements  Includes a feedback loop to the process  May be manual, automated, or both Measurement + feedback ++

9 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Quality Assurance  Consists of the auditing and reporting functions of management  Goal:  to provide management with the data necessary to be informed about product quality,  thereby gaining insight and confidence that product quality is meeting its goal ++

10 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Quality Costs 1.Prevention costs: quality planning, formal technical reviews, test equipment, training 2.Appraisal costs include activities to gain insight into product condition the “first time through” each process: in-process & inter- process inspection, equipment calibration & maintenance, testing 3.Failure costs: Internal Failure costs: rework, repair, failure mode analysis External Failure costs: complaint resolution, product return & replacement, help line support, warranty work ++

11 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 SOFTWARE QUALITY Conformance to  explicitly stated functional and performance requirements,  explicitly documented development standards, and  implicit characteristics that are expected of all professionally developed software ++

12 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 DEFINITION (2) Three important points of the definition: 1.Software requirements are the foundation from which quality is measured 2.Specified standards define a set of development criteria that guide the engineering 3.A set of implicit requirements often goes unmentioned (eg. Ease of use, maintainability) ++

13 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Software Quality Assurance Formal Technical Reviews SQA Test Planning & Review Measurement Analysis & Reporting Process Definition & Standards

14 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 SQA Activities  Software engineers address quality by  applying solid technical methods & measures,  conducting formal technical reviews, and  performing well-planned testing  SQA group assists the software team in achieving a high quality product by addressing  quality assurance planning,  oversight,  record keeping,  analysis, &  reporting ++

15 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Reviews & Inspections... there is no particular reason why your friend and colleague cannot also be your sternest critic. Jerry Weinberg

16 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 What Are Reviews?  a meeting conducted by technical people for technical people  a technical assessment of a work product created during the software engineering process  a software quality assurance mechanism  a training ground

17 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Constraints  Between 3 and 5 people  Advance preparation should occur but should require no more than 2 hours of work for each person  Duration of review meeting should be less than 2 hours ++

18 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 What Reviews Are Not! They are not: a project budget summary a scheduling assessment an overall progress report a mechanism for reprisal or political intrigue!!

19 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 The Players review leader producer recorder reviewer standards bearer (SQA) maintenanceoracle user rep

20 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Conducting the Review be prepared—evaluate product before the review review the product, not the producer keep your tone mild, ask questions instead of making accusations stick to the review agenda raise issues, don't resolve them avoid discussions of style—stick to technical correctness schedule reviews as project tasks record and report all review results

21 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Review Guidelines  Review the product, not the producer  Set an agenda and maintain it  Limit debate and rebuttal  Enunciate the problem areas, but don’t attempt to solve every problem noted  Take written notes  Limit the number of participants and insists upon advance preparation  Develop a checklist for each product that is likely to be reviewed  Allocate resources and schedule time for FTRs  Conduct meaningful training for all reviewers  Review your early review ++

22 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Review Options Matrix trained leader agenda established reviewers prepare in advance producer presents product “reader” presents product recorder takes notes checklists used to find errors errors categorized as found issues list created team must sign-off on result IPR—informal peer review WT—Walkthrough IN—Inspection RRR—round robin review IPRWTIN RRR nomaybemaybemaybenomaybenonononoyesyesyesyesnoyesnonoyesyes yesyesyesnoyesyesyesyesyesyesyesyesyesnonoyesnonoyesmaybe * *

23 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Metrics Derived from Reviews inspection time per page of documentation inspection time per KLOC or FP errors uncovered per reviewer hour errors uncovered per preparation hour errors uncovered per SE task (e.g., design) number of minor errors (e.g., typos) number of errors found during preparation number of major errors (e.g., nonconformance to req.) (e.g., nonconformance to req.) inspection effort per KLOC or FP

24 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 Statistical SQA Product & Process measurement... an understanding of how to improve quality... collect information on all collect information on all defects find the causes of the find the causes of the defects move to provide fixes for move to provide fixes for the process

25 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 ________ stoppage

26 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 SOFTWARE RELIABILITY  The probability of failure-free operation of a computer program in a specified environment for a specified time  Measures: MTBF = MTTF + MTTR  Availability = (MTTF/(MTTF+MTTR)) * 100%  Software safety is  SQA activity that focuses on the identification & assessment of potential hazards that may affect software negatively and cause system to fail ++

27 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 ISO 9000  Describes quality assurance elements in generic terms that can be applied to any business regardless of the products or services offered  Elements of quality assurance system:  organizational structure,  procedures,  processes, and  resources to implement quality planning,  quality control,  quality assurance, and  quality improvement  ISO 9001 – for software engineering ++

28 These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001 SQA plan  Provides road map for instituting software quality assurance  The plan serves as template for SQA activities  Contents: initial section – purpose and scope management section – organizational structure documentation section – project documents, models, technical documents, user documents test section tools & methods, SCM, contract, records maintenance, training, risk ++