BeLearning: Designing Accessible Web Applications Helmut Vieritz, Author MuLF-Center, Department of Mathematics & Natural Sciences Berlin University of Technology Sekr. MA 7-2, Str. des 17. Juni 136 D-10623 Berlin, Germany vieritz@math.tu-berlin.de Sabina Jeschke, Coauthor RUS - Center of Information Technologies Department for CS, EE & IT University of Stuttgart Rechenzentrum, Allmandring 30a 70550 Stuttgart, Germany sabina.jeschke@rus.uni-stuttgart.de Abstract Flexibility and adaptivity are two of the outstanding characteristics of new media and new technologies. These properties allow new methods to provide physically chal- lenged people with appropriate information. To build ac- cessible Web applications, one has to respect the needs from the beginning of the design process. However, it is difficult to integrate the requirements of accessibility guidelines into modern web design. Based on recent pro- posals for model-based Web application development, we discuss the essential modeling requirements to ensure en- hanced accessibility in Web applications. 1. Introduction Web-based platforms offer a great potential to provide physically challenged people with information and knowl- edge. First, the possibilities to distribute materials and communication between all participants have been dra- matically improved by computers and the Web. Secondly, based on the separation of content and representation, the same information can be presented through different me- dia types adapted to different sensory perceptions. Finally, in comparison to traditional material and media types modern information and communication technologies in- clude new approaches concerning far-ranging user adap- tivity. Web-based information platforms can provide the user with additional information about multimedia con- tent, navigation and presentation suited to his own partic- ular needs. Especially web-based technologies offer a wide range of possibilities for new concepts supporting individual de- mands and interests. The two deciding factors are given by the interaction capability and the ability to adapt to the user, both practically unachievable using traditional me- dia. These two features are the key to extend the method- ology of information and knowledge propagation as well as the support of individual strategies - new media thus possess the potential to assist physically challenged peo- ple in transcending the disadvantages in education. Unfor- tunately, current web platforms are often not accessible to all users. Additional demands of accessible applications are discussed in section 2. Experts often underline that accessibility does not re- quire extra effort if the demands are respected from the beginning of the design process. Nevertheless, current guidelines are difficult to understand and to use. Acces- sibility stays to be understood as expert knowledge. The WAI (Web Accessibility Initiative) has reacted on this issue and many introductions and “easy to understand”- instructions have been published. The here presented BeLearning approach aims at sim- plifying the development process of accessible applica- tions based on the idea that the early design process must already include the needs of accessibility. Therefore, the potential of model-based Web engineering has been eval- uated since it requires an accurate planning right from the beginning. Web engineering expands classical approaches of model-based software engineering with additional mod- els corresponding to the demands of web applications. Additionally, user classification, navigation and presenta- tion models are integrated. Some approaches even facil- itate access to navigation and hyperlinks with additional annotation during the design process. Recent research for model-based web application development concepts is presented in section 3. Even model-based development requires the early in- tegration of all demands of the to-be web platform. The description of the application with models can be used to integrate accessibility features. Based on semantic con- tent encoding [9] and model-based development, a broad