A framework for capturing the relationship between usability and software architecture

Eelke Folmer, Jilles van Gurp, Jan Bosch Department of Mathematics and Computing Science University of Groningen, PO Box 800, 9700 AV, the Netherlands [email protected], [email protected], [email protected] http://www.rug.nl/informatica/search Abstract Usability is increasingly recognized as an essential factor that determines the success of software systems. Practice shows that for current software systems, most usability issues are detected during testing and deployment. Fixing usability issues during this late stage of the development proves to be very costly. Some usability improving modifications such as usability patterns may have architectural implications. We believe that the software architecture may restrict usability. The high costs associated with fixing usability issues during late stage development prevent developers from making the necessary adjustments for meeting all the usability requirements. To improve upon this situation we have investigated the relationship between usability and software architecture to gain a better understanding of how the architecture restricts the level of usability. Our paper makes a number of contributions; a framework is presented that expresses the relationship between usability and software architecture. The framework consists of an integrated set of design solutions such as usability patterns and usability properties that have been identified in various cases in industry, modern day software, and literature surveys. These solutions, in most cases, have a positive effect on usability but are difficult to retrofit into applications because they have architectural impact. Our framework may be used to guide and inform the architectural design phase. This may decrease development costs by reducing the amount of usability issues that need to be fixed during the later stages of development.