INF3705 Key points

A generic system is - answer-adapted and specialized to meet specific requirements for functionality, target platform, or operational configuration. A hazard-driven approach may be used to - answer-understand the safety requirements for safety-critical systems. A model is an abstract view of - answer-a system that deliberately ignores some system details. Complementary system models can be developed to show the system's context, interactions, structure, and behaviour. A range of different models may be produced during _____ which include _____ - answer-an object-oriented design process. These include static models (class models, generalization models, association models) and dynamic models (sequence models, state machine models). A RESTful approach uses - answer-the http and https protocols for service communication and maps operations on the standard http verbs POST, GET, PUT, and DELETE. A separate team should be responsible for - answer-testing a system before it is released to customers. A software architecture - answer-is a description of how a software system is organized. Acceptance testing is a - answer-user testing process in which the aim is to decide if the software is good enough to be deployed and used in its planned operational environment. Activity diagrams - answer-may be used to model the processing of data, where each activity represents one process step. Agile development practices - answer-include requirements expressed as user stories, pair programming, refactoring, continuous integration, and test-first development. Agile methods - answer-are iterative development methods that focus on reducing process overheads and documentation and on incremental software delivery. They involve customer representatives directly in the development process. agile or a plan-driven approach - answer-The decision on whether to use an agile or a plan-driven approach to development should depend on the type of software being developed, the capabilities of the development team, and the culture of the company developing the system. In practice, a mix of agile and plan-based techniques may be used Application frameworks are - answer-collections of concrete and abstract objects that are designed for reuse through specialization and the addition of new objects. They usually incorporate good design practice through design patterns. Application system reuse is - answer-concerned with the reuse of large-scale, off-the-shelf systems. These provide a lot of functionality, and their reuse can radically reduce costs and development time. Architectural design decisions include - answer-decisions on the type of application, the distribution of the system, the architectural styles to be used, and the ways in which the architecture should be documented and evaluated. Architectural patterns are - answer-a means of reusing knowledge about generic system architectures and describe the architecture, explain when it may be used, and point out its advantages and disadvantages. Architectures may be documented - answer-from several different perspectives or views. Behavioural models - answer-are used to describe the dynamic behaviour of an executing system. Business, organizational, and technical changes inevitably lead to - answer-changes to the requirements for a software system. Requirements management is the process of managing and controlling these changes. Commonly used Architectural patterns include - answer-model-view-controller, layered architecture, repository, client-server, and pipe and filter. Component interfaces must be - answer-defined precisely so that other objects can use them. Conceptual systems design is a key activity where - answer-high-level system requirements and a vision of the operational system is developed. Configuration management - answer-is the process of managing changes to an evolving software system. It is essential when a team of people is cooperating to develop software. Context models show - answer-how a system that is being modelled is positioned in an environment with other systems and processes. They help define the boundaries of the system to be developed. Dependability of a computer system is - answer-a system property that reflects the user's degree of trust in the system. Dependable programming relies on - answer-including redundancy in a program as checks on the validity of inputs and the values of program variables. Dependable system architectures are - answer-system architectures that are designed for fault tolerance. Design and implementation processes - answer-are concerned with transforming a requirements specification into an executable software system. Development testing includes - answer-unit testing in which you test individual objects and methods; component testing in which you test related groups of objects; and system testing in which you test partial or complete systems. Development testing is the responsibility of - answer-the software development team. Different procurement processes are - answer-used for off-the-shelf application systems, configurable COTS systems, and custom systems. Examples of these general models include? - answer-the waterfall model, incremental development, and reusable component configuration and integration. For custom systems, the costs of software maintenance - answer-usually exceed the software development costs. Functional reliability requirements are - answer-requirements for system functionality, such as checking and redundancy requirements, which help the system meet its non-functional reliability requirements. Functional requirements - answer-are statements of the services that the system must provide or are descriptions of how some computations must be carried out. General process models - answer-describe the organization of software processes. Generic models of application systems architectures helps us how - answer-help us understand the operation of applications, compare applications of the same type, validate application system designs, and assess large-scale components for reuse. Graphical workflow languages, such as BPMN, may be used - answer-to describe a business process and the services used in that process. These languages can describe interactions between the organizations that are involved. Language processing systems are - answer-used to translate texts from one language into another and to carry out the instructions specified in the input language. They include a translator and an abstract machine that executes the generated language Legacy systems are - answer-older software systems, developed using obsolete software and hardware technologies, that remain useful for a business. Model checking is a - answer-formal approach to static analysis that exhaustively checks all states in a system for potential errors. Model-driven engineering - answer-is an approach to software development in which a system is represented as a set of models that can be automatically transformed to executable code. Most software development is - answer-host-target development. Non-functional requirements - answer-often constrain the system being developed and the development process being used. These might be product requirements, organizational requirements, or external requirements. They often relate to the emergent properties of the system and therefore apply to the system as a whole. Open-source development involves - answer-making the source code of a system publicly available. Possible views include - answer-a conceptual view, a logical view, a process view, a development view, and a physical view. Potential problems with application system reuse include - answer-lack of control over functionality, performance, and system evolution; the need for support from external vendors; and difficulties in ensuring that systems can interoperate. Process improvement - answer-is the process of improving existing software processes to improve software quality, lower development costs, or reduce development time. It is a cyclic process involving process measurement, analysis, and change. Processes - answer-should include activities to cope with change and may be structured for iterative development and delivery so that changes may be made without disrupting the system as a whole. Properties of a system such as ____ are influenced by the architecture used. - answer-performance, security, and availability. Refactoring - answer-making small program changes that preserve functionality, can be thought of as preventative maintenance. Reliability metrics include - answer-probability of failure on demand (POFOD), rate of occurrence of failure (ROCOF), and availability (AVAIL). Reliability requirements can be defined - answer-quantitatively in the system requirements specification. Requirements elicitation - answer-is an iterative process that can be represented as a spiral of activities— requirements discovery, requirements classification and organization, requirements negotiation, and requirements documentation. Requirements engineering - answer-is the process of developing a software specification. Requirements for a software system - answer-set out what the system should do and define constraints on its operation and implementation. Requirements specification - answer-is the process of formally documenting the user and system requirements and creating a software requirements document. Requirements validation - answer-is the process of checking the requirements for validity, consistency, completeness, realism, and verifiability. Safety and dependability cases do what? - answer-collect all of the evidence that demonstrates a system is safe and dependable. Safety-critical systems are - answer-systems whose failure can lead to human injury or death.