Proxy Viewpoints Model-based Requirements Discovery (PVRD)
Project Keywords:
Software Requirements Engineering, Viewpoints, Requirements Discovery and Analysis, Missing Requirements
Project Summary:
This research project addresses the problem of “missing requirements” in software requirements specification (SRS) expressed in natural language. Due to rapid changes in technology and business frequently witnessed over time, the original SRS documents often experience the problems of missing, not available, and hard-to-locate requirements. Such problems can be further decomposed into the following subproblems: 1) Earlier solutions do not consider missing requirements from multiple viewpoints; 2) SRS documents with many missing requirements typically tend to be poorly structured and maintained as well as hard-to-trace; 3) SRS documents with missing requirements represent an incomplete domain model; and finally 4) Manual discovery (identification and incorporation) of missing requirements is highly labor intensive and error-prone. These inherently rigid subproblems do not allow efficient adaptation of SRS changes and improvements. Most SRS documents today are plagued by a combination of one or more of these problems, and they become even more prevalent while dealing with legacy status (Alderson and Shah, 1999) SRS. Therefore, there is a strong need to develop a new methodology that can provide improved solutions to these problems and lengthen the life span of SRS.
In this research, a new methodology entitled “Proxy Viewpoints Model-based Requirements Discovery (PVRD)” is developed to attempt to meet this need. Through the requirements discovery and analysis process, the PVRD methodology provides a way to construct proxy viewpoints models from legacy status natural language SRS documents. Proxy viewpoints is an approximation of viewpoints that would have been constructed if the requirements of the domain were well-engineered from the beginning of a software development life cycle by using one of the viewpoints oriented requirements engineering methods such as VORD (Kotonya and Sommerville, 1996; 1998).
The PVRD methodology consists of four models: viewpoints model, enterprise model, missing requirements types categorization model, and requirements discovery and analysis model. The viewpoints model represents different perspectives or views for a coverage of direct and indirect stakeholders that need to be identified and incorporated into the legacy status software system requirements. The enterprise model provides a way of categorizing requirements based on systems engineering design process models. The missing requirements types categorization model provides a method to project a requirements space that may contain a specific type of missing requirements. The requirements discovery and analysis model provides a method to retrieve requirements of interest by using the requirements term expansion method that automatically generates a list of “potential query terms” which could assist analysts in acquiring more knowledge about the domain of interest by performing a “complete search” of available requirements resources.
Based on this integrated framework, the PVRD methodology is able to create a proxy viewpoints model and provides a new way of discovering missing requirements while improving the requirements representation space through a new indexing structure that supports multiple viewpoints from many stakeholders in a large-scale complex software system.
Well-designed explanatory scenario-based multiple-case studies are developed in the finance application system domain and educational information management system domain, not only as a way to validate the methodology but also to show its uniqueness and novelty and to provide exemplary guidance for researchers from academia and real practitioners from industry. Various evidence and findings that support the propositions of this study validate that the PVRD methodology provides an integrated environment that supports a requirements discovery and analysis process as well as efficient management.
Project Members/Collaborators:
Dr. Seok-Won Lee (PI) and Dr. David C. Rine (George Mason University, NASA NET Research Group, NASA Headquarter, Washington DC.)
Project Sponsor:
This project is partially funded by NASA.