A groupware interface to a shared file system

Abstract

Current shared file systems (NFS and SAMBA) are based on the local area network model. To these file systems, performance is the major issue. However, as the Internet grows, so does the distance between users and the Local Area Network. With this increase in distance, the latency increases as well. This creates a problem when multiple users attempt to work in a shared environment. Traditionally, the only way to collaborate over the Internet required the use of locks. These requirements motivated the creation of the State Difference Transformation algorithm that allows users non-blocking and unconstrained interaction across the Internet on a tree based structure. Fine Grain Locking, on the other hand, allows a user the ability to set a lock on a character or range of characters while using a form of the transformation algorithm listed above. This thesis proposes an implementation that integrates these two technologies as well as demonstrating the effectiveness and flexibility of State Difference Transformation. The implementation includes two applications that can be used to further research in both the transformation and locking communities. The first application allows users to create tests for SDT and Fine Grain Locking and verify the correctness of the algorithms in any given situation. The second application then furthers this research by creating a real-world groupware interface to a shared file system based on a clientserver architecture. This implementation demonstrates the usability and robustness of these algorithms in real world situations.