Rekayasa Perangkat Lunak

REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 Bagian 10 FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 2

Outline of this presentation Software Quality Mc Call’s Triangle of Quality Mc Call’s Software Quality Factors Product Operation Product Revision Product Transition FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10

McCall’s Triangle of Quality b l y F e x T s P o r R u I p C c E f g U O D A N S V FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10

McCall’s Triangle of Quality Correctness Traceability Completeness Reliability Consistency Accuracy Efficiency Error tolerance Execution efficiency Integrity Storage efficiency Access Control Usability Access Audit McCall’s Triangle of Quality Operability Training Maintainability Communicativeness Simplicity Flexibility Conciseness Instrumentation Testability Self-descriptiveness Expandability Portability Generality Modularity Reusability SW independence HW independence Communication commonality Interoperability Data commonality

McCall’s Software Quality Factors (1) Product Operation Correctness Reliability Efficiency Integrity Usability FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 7

McCall’s Software Quality Factors (2) Product Revision Maintainability Flexibility Testability FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 7

McCall’s Software Quality Factors (3) Product Transition Portability Reusability Interoperability FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 7

McCall’s Software Quality Factors (4) Product Operation Correctness satisfies a specification ideal quality established w.r.t. the requirements specification absolute FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 8

McCall’s Software Quality Factors (5) Product Operation Reliability performs with precision statistical property probability that software will operate as expected over a given period of time relative FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 8

McCall’s Software Quality Factors (6) Product Operation Efficiency utilization of system resources Integrity control of access by the unauthorized Usability effort required to learn, operate, etc. ability of end-users to easily use software extremely subjective FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 8

McCall’s Software Quality Factors (7) Product Revision Maintainability effort required to correct FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 9

McCall’s Software Quality Factors (8) Product Revision Flexibility effort required to modify ability to add or modify functionality addresses adaptive and perfective maintenance problem: evolution of implementation is too easy evolution should start at requirements or design FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 9

McCall’s Software Quality Factors (9) Product Revision Testability effort required to test ease of establishing desired properties performed by formal analysis or testing internal quality FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 9

McCall’s Software Quality Factors (10) Product Transition Portability dependency on hardware and operating environments ability to execute in new environments with minimal effort may be planned for by isolating environment- dependent components necessitated by the emergence of highly- distributed systems (e.g., the Internet) an aspect of heterogeneity FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 10

McCall’s Software Quality Factors (11) Product Transition Reusability degree to which program can be used in other applications ability to construct new software from existing pieces must be planned for occurs at all levels: from people to process, from requirements to code FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 10

McCall’s Software Quality Factors (12) Product Transition Interoperability effort required for 2 systems to communicate ability of software (sub)systems to cooperate with others easily integratable into larger systems common techniques include APIs, plug-in protocols, etc. FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 10

REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 Software Qualities Qualities (a.k.a. “ilities”) are goals in the practice of software engineering External vs. Internal qualities Product vs. Process qualities FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10

REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 Software Quality External vs. Internal Quality External qualities are visible to the user reliability, efficiency, usability, etc Internal qualities are the concern of developers they help developers achieve external qualities maintainability, testability, flexibility,etc FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10

REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 Software Quality Product vs. Process Qualities Product qualities concern the developed artifacts maintainability, understandability, performance Process qualities deal with the development activity products are developed through process maintainability, productivity, timeliness FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10

REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 Software Quality Software Process Qualities Process is reliable if it consistently leads to high- quality products Process is robust if it can accommodate unanticipated changes in tools and environments Process performance is productivity Process is evolvable if it can accommodate new management and organizational techniques Process is reusable if it can be applied across projects and organizations FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10

REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 Software Quality Assesing Software Qualities Qualities must be measurable Measurement requires that qualities be precisely defined Improvement requires accurate measurement Currently most qualities are informally defined and are difficult to assess FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10

REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 Software Quality Software Engineering “Axioms” Adding developers to a project will likely result in further delays and accumulated costs Basic tension of software engineering better, cheaper, faster — pick any two! functionality, scalability, performance — pick any two! FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10

REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10 Software Quality Software Engineering “Axioms” The longer a fault exists in software the more costly it is to detect and correct the less likely it is to be properly corrected Up to 70% of all faults detected in large-scale software projects are introduced in requirements and design detecting the causes of those faults early may reduce their resulting costs by a factor of 100 or more FAKULTAS TEKNOLOGI INFORMASI REKAYASA PERANGKAT LUNAK – KP146 – 3 SKS – BAG 10

Finished, Questions?