The good news is for the most generic quality attributes (availability, interoperability, modifiability, performance, security, testability, usability) you have generic quality attribute scenarios with the most common aspects to take into account. Starting to write may sound difficult because you may not know some measures and characteristics related to quality attributes. Getting started writing Quality Attribute Scenarios The process informs the operator of the messageвЂ™s receipt, and the system continues to operate with no downtime. Response: inform operator, continue to operateДЄn unanticipated external message is received by a process during normal operation. Source of Stimulus: external to the system Response Measure: This is the measure that should be tested for the response to test if the requirement is well implemented. Response: The is the response of the artifact according to the received stimulus. This can be a component of the system, the whole system, or several systems. For instance, the system may be running in normal conditions, under heavy traffic, or with a high latency or any relevant state.ДЄrtifact: The artifact that receives the stimulus. Stimulus: The stimulus is a condition that requires a response when it arrives at a system.Д®nvironment: The environment where the stimulus occurs. Source of Stimulus: An entity capable of creating stimulus (internal or external people, a computer system, etc) A quality attribute scenario is composed of six elements (as the following Figure illustrates): A quality attribute scenario is an unambiguous way to specify a testable quality attribute. To define a tangible quality attribute, a good starting point is to write a quality attribute scenario. This allows teams responsible to implement certain tasks to know when they did a good job, according to some stakeholders, to complete that requirement. First of all, all quality attributes must be measurable in some way. Everyone is going to say it must be secure - whatever that means.Д«ut those situations can be avoided with some work and preparation. He would probably say, вЂњthe minimum time possible.вЂќ Most of the time they are implicit or said without much thought behind them.ДЄ real-world example is if youвЂ™re in charge of developing certain features and you ask your boss about the time that the system should take to complete a task. They're only verbally said alongside functional requirements. Quality attributes, most of the time, are not written. An example of a QA is how fast the function must be performed or how resilient it must be to an erroneous input, the time to deploy the product, or a limitation on operational costs. In other words, a quality attribute (aka as Non-Functional Requirements) is what makes a system good with respect to a specific stakeholder.

A quality attribute ( QA) is a measurable or testable property of a system that is used to indicate how well the system satisfies the needs of its stakeholders.

Stimulus artifact meaning