Book Image

Mastering Non-Functional Requirements

By : Sameer Paradkar
Book Image

Mastering Non-Functional Requirements

By: Sameer Paradkar

Overview of this book

Non-functional Requirements are key to any software/IT program and cannot be overlooked or ignored. This book provides a comprehensive approach to the analysis, architecture, and measurement of NFRs. It includes considerations for bespoke Java, .NET, and COTS applications that are applicable to IT applications/systems in different domains. The book outlines the methodology for capturing the NFRs and also describes a framework that can be leveraged by analysts and architects for tackling NFRs for various engagements. This book starts off by explaining the various KPIs, taxonomies, and methods for identifying NFRs. Learn the design guidelines for architecting applications and systems relating to NFRs and design principles to achieve the desired outcome. We will then move on to various key tiers/layers and patterns pertaining to the business, database, and integrating tiers. After this, we will dive deep into the topics pertaining to techniques related to monitoring and measurement of NFRs, such as sizing, analytical modeling, and quality assurance. Lastly, we end the book by describing some pivotal NFRs and checklists for the software quality attributes related to the business, application, data, and infrastructure domains.
Table of Contents (14 chapters)

NFR - Sizing


Software Non-functional Assessment Process (SNAP), a measurement of non-functional software size. SNAP point sizing is a complement to a function point sizing, which measures functional software size. It is a product of the International Function Point Users Group (IFPUG), and is sized using the SNAP manual.

The overall size of software consists of separate components, functional and non-functional, for example, 400 function points and 200 SNAP points. The two sizes do not sum up to one single size. The IFPUG functional sizing methodology does not change when measuring the non-functional requirements using SNAP. Non-functional sizing requires recognition of similar artifacts of software used to measure functional size, for example, data element types (DETs) and file types referenced (FTRs).

Separating functional and non-functional requirements is important when performing a cost forecast (or other forecast, such as scheduling or staffing) for software development. In principle...