Methodologies and techniques for extracting functional and non-functional requirements used for RAINBOW project

The intention behind the requirement elicitation, is to identify quality user requirements that can be implemented into software development projects. The requirements the engineering method follows ISO/IEC/IEEE 29148:2018 and describes two main processes or practices:

1. Stakeholder Requirements Definition Process. The purpose here is to define the requirements for a system that can provide the services needed by users and other stakeholders in a defined environment. Main output concerning Stakeholder Requirements Specification (StRS).
2. Requirements Analysis Process. The purpose here is to transform the stakeholder, requirement-driven view of desired services into a technical view of a required product that could deliver those services. Main output related with System Requirements Specification (SyRS) and Software Requirements Specification (SRS).

Techniques for the Requirements Elicitation

Eliciting requirements is very important in product development lifecycle. As such, the requirements must be complete, clear, correct, and consistent as they are providing critical solutions to the business needs.

International Institute of Business Analysis (IIBA) published BABOK, a collection of standard business analysis practices which assists analysts develop an in-depth understanding of core concepts and stay up to date with developments [1]. BABOK, lists a number of requirements elicitation techniques. RAINBOW project supports five of them: Brainstorming, Document Analysis, Focus Groups, Interviews, Survey/Questionnaire.

• Brainstorming,           is a technique intended to produce a broad or diverse set of options. Brainstorming works by focusing on a topic or problem and then coming up with many possible solutions to it.  Facilitated properly (without censoring ideas) and executed with the right audience (representatives of each group, SMEs, stakeholders), brainstorming can be productive.
• Document analysis, is a technique used to elicit project requirements information by studying existing documentation, and other relevant information, from industries and competitors that may have similar systems. It may include the analysis of existing system specifications, problem reports, and many others.
• A focus group, is composed of pre-qualified individuals, whose objective is to discuss and comment on a specific topic. This could lead participants to re-evaluate their own perspectives in light of others’ experiences. Business analysts manage the administrative pre-work, facilitate the session and produces the report.
• In an interview, the interviewer formally or informally directs questions to a stakeholder in order to gather answers that will be used to define requirements. Interviews are of two basic types: i) Structured Interview, where the interviewer has a pre-defined set of questions and is looking for answers. Ii) Unstructured Interview,without any pre-defined questions, the interviewer and the interviewee discuss topics of interest in an open-ended way.
• Survey/questionnaire. While they preclude the opportunity for in-person, ad hoc conversations, surveys are useful for quickly gathering data from a large group of participants. As with selecting stakeholders, a successful survey or questionnaire must have well-chosen participants. Surveys can be structured to offer open-ended input, depending on the needs of the project at hand. Survey wording must be unambiguous and precise.

RAINBOW approaches interviewing the different type of stakeholders through interviews and questionnaires. Eliciting requirements results in a type of raw requirements, which are collected by RAINBOW system that runs an iterative internal process in order to produce some outcomes [2].

The outcomes are compared with the technicality of the system and produce the good and necessary requirement for the development of RAINBOW platform. In addition to requirements gathering, a document analysis through a     thorough industry and literature review has  been conducted, in order to validate the requirements as well as identify standards and constraints which play an important       role in the attempt to receive requirements      of high quality.

The techniques were constantly reviewed by the RAINBOW focus groups also provided valuable feedback on the questionnaire respondents as well as the interview participants.

[1] “A Guide to the Business Analysis Body of Knowledge (BABOK Guide) is a standard for the practice of business analysis created and maintained by IIBA (International Institute of Business Analysis),” [Online].

[2] D. Pandey, S. U. and A. K. Ramani, “An effective requirement engineering process model for software development and requirements management,” in International Conference on Advances in Recent Technologies in Communication and Computing, IEEE, 2010