Quantitative and Qualitative Support for Non-Functional Requirements in Stock Trading Systems

The efficient functioning of financial markets is important for growth across the world, affecting businesses, society and individuals. Stock trading, a key activity within financial markets, is undergoing major transformation fuelled by advances in information systems techniques. Our motivation is in the development of stock trading systems that are robust and are transparent to regulators, traders and the public. Specifically, the work presented in this paper focuses on the way that quality factors may be considered at the requirements phase when designing systems to support sock trading processes. We focus on three quality factors namely performance, availability and security. We introduce a modeling paradigm that extends the well-known UML Activity model to explicitly represent these three quality factors and augment this through quantitative and qualitative reasoning. The approach is exemplified through the use of a small aspect of a stock trading process, dealing with the ‘order crossing’ part, taken from the practices of an international firm.