24 CHAPTER ◆ 2 Key Concepts and Definitions of Terms
2.24. Quality Planning
Part of quality management focuses on setting quality objectives and specifying necessary
operational processes and related resources to fulfill Quality Money Management objec-
tives. A quality plan is a document specifying which procedures and associated resources
will be applied by whom and when to a specific project.2.25. Software Quality Attributes
A software quality attribute is an observable characteristic of a system. A quality attribute
requirement is the threshold value a system must meet with respect to a quality attribute.● Functionality. These usually represent the main product features that are defined
within the business domain of the solution being developed.- Capacity. For example, can the software listen to 50,000 options at the same
time? - Extensibility. For example, can I add new markets to the system sometime in the
future? Can the software be augmented? - Interoperability. For example, will the system work with our legacy execution
system? - Availability. For example, will the system be up over night?
- Scalability. For example, can I add 10,000 more options?
- Security.
- Recoverability. For example, what if I have positions over night? What if the net-
work fails?
● Usability.
● Performance. For example, how many milliseconds will it take for my order to
reach the exchange?
● Reliability. For example, does it ever make a mistake?
● Supportability.
Quality assurance testing in K|V 3.4 will make sure all requirements are met.2.26. Stable or Stationary System
A stationary process or system, also called an in-control process, is a stochastic process
whose probability distribution is constant, that is, the mean and variance do not change
over time. We can also describe a stable or stationary system as one that contains no spe-
cial cause variation, only common cause variation. A stable system can also be a process
where all the causes of variation are known and accounted for, leaving the system to be
governed only by common causes of variation, so that process outputs are then fairly pre-
dictable. Several conditions will indicate that a process is “ out of control. ” Such conditions
are often viewed in control chart tests. Stability involves achieving consistent and, ulti-
mately, higher process yields through the application of an improvement methodology.