Copyright © Jerzy R. Nawrocki ISO 9126 and Non-functional Requirements Requirements Engineering & Project Management Lecture 4

J.Nawrocki, ISO 9126 Introduction Project Vision Business Process Descr. / Operational Scenarios Functional Requirements Non-functional Requirements Development, Implem. & Testing Transition

J.Nawrocki, ISO 9126 Introduction Project Vision Business Process Descr. / Operational Scenarios Functional Requirements Non-functional Requirements Development, Implem. & Testing Transition ISO 9126

J.Nawrocki, ISO 9126 Introduction ISO 9126: Software Engineering – Product Quality Part 1: Quality Model Part 2: External Metrics Part 3: Internal Metrics Part 4: Quality-in-use Metrics

J.Nawrocki, ISO 9126 Agenda Introduction Quality Model Quality in Use Internal and External Quality

J.Nawrocki, ISO 9126 Quality in the lifecycle Process quality Internal quality attributes External quality attributes Quality in use attributes Impacts Development process Software productEffect of using product

J.Nawrocki, ISO 9126 Quality in the lifecycle Internal quality External quality Quality in use Indicates Software productEffect of using product Indicates

J.Nawrocki, ISO 9126 External and Internal Quality Maintainability Functionality Reliability Usability Efficiency Portability External and Internal Quality Characteristics

J.Nawrocki, ISO 9126 Quality-in-use Effectiveness Productivity Safety Satisfaction Quality-in-use Characteristics

J.Nawrocki, ISO 9126 Agenda Introduction Quality Model Quality in Use Internal and External Quality

J.Nawrocki, ISO 9126 Quality-in-use Effectiveness Productivity Safety Satisfaction Quality-in-use Characteristics

J.Nawrocki, ISO 9126 Quality-in-use Metrics Task effectiveness – What proportion of the goals of the tasks is achieved correctly? Task completion – What proportion of the tasks is completed (number of tasks completed / total number of tasks attempted)? Error frequency – What is the frequency of errors? Effectiveness

J.Nawrocki, ISO 9126 Quality-in-use Metrics Task time – How long does it take to complete a task? Task efficiency – How efficient are the users (Task effectiveness / Task time)? Economic productivity – How cost-effective is the user (Task effectiveness / total cost of the task)? Productivity

J.Nawrocki, ISO 9126 Quality-in-use Metrics User health and safety – What is the incidence of health problems among users of the product? Economic damage – What is the incidence of economic damage? Safety

J.Nawrocki, ISO 9126 Quality-in-use Metrics Satisfation scale – How satisfied is the user? Satisfation questionnaire – How satisfied is the user with specific software features? Satisfaction

J.Nawrocki, ISO 9126 Agenda Introduction Quality Model Quality in Use Internal and External Quality

J.Nawrocki, ISO 9126 External and Internal Quality Maintainability Functionality Reliability Usability Efficiency Portability External and Internal Quality Characteristics

J.Nawrocki, ISO 9126 Functionality Suitability Accuracy Interoperability Security Functionality compliance

J.Nawrocki, ISO 9126 Reliability Maturity Fault tolerance Recoverability Compliance

J.Nawrocki, ISO 9126 Usability Uderstandability Learnability Operability Attractiveness Compliance

J.Nawrocki, ISO 9126 Efficiency Time behaviour Resource utilization Compliance

J.Nawrocki, ISO 9126 Maintainability Analysability Changeability Stability Tastability Compliance

J.Nawrocki, ISO 9126 Portability Adaptability Installability Co-existance Replaceability Compliance

J.Nawrocki, ISO 9126 Homework Prepare a spreadsheet that would support collection of non-functional requirements based on ISO Usability UnderstandabilityH LearnabilityH OperabilityL

J.Nawrocki, ISO 9126 Summary Quality views: Quality-in-use, External & Internal quality Quality characteristics: External & Internal subcharacteristics Quality metrics – Examples