In general, the World Wide Web has a high potential as a platform for distributed groupware systems. Authors create and change documents locally and upload them to a Web server, where they can be accessed by their collaborators. However, Web browsers and servers which implement the protocol HTTP are mostly limited to provide reading access to Web documents. For this reason, existing Web-based groupware systems (e.g. the BSCW system) are implemented using client/server side scripting. These scripts are used to implement the basic operations needed for this kind of applications.

The protocol WebDAV (World Wide Web Distributed Authoring and Versioning) which was developed as an extension of HTTP/1.1 by the WebDAV working group of the Internet Engineering Task Force (IETF) and defines new methods which offer additional services for editing and managing files on remote Web servers in a structured way (e.g. locking, version management, metadata management, etc.). When using WebDAV, the Web is becoming a rich infrastructure for collaborative applications, where the Web-DAV methods can be used to implement the basic operations needed (e.g. copy, delete, upload, assign metadata to documents, etc.). Scripting can be used in this context as well, but not for implementing the basic tasks of collaboration, but to simplify maintenance of the application.

The paper is structured as follows: In Section 2 we introduce the functionality of WebDAV. In Section 3, we briefly summarize related work in the area of implementing Web-based groupware systems and we give a short description of two systems, BSCW and DReSS. Furthermore, we present the advantages of using WebDAV for these kind of appli- cations. Section 4 identifies the requirements of a Web browser user interface to use the protocol WebDAV and defines the implemented extensions within the Web browser “Cineast”. Section 5 describes a simple collaborative application using both the WebDAV-compliant Web browser and Web server (e.g. the Apache Web server extended with the module mod_dav which implements the WebDAV server side). This application is roughly comparable with the core functionality of the BSCW system and supports a project repository within an organization where the users want to share project related documents and folders. Some features of BSCW (e.g. user administration, group management, awareness information) are not yet implemented in our project repository. Section 6 offers concluding remarks and a brief description of future work.

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