Remote File System Notification Service

01.06.2005

Abstract
Digital information is generally stored as files on a file system. Hence, if somebody adds, changes or removes information on the Internet, it can be tracked back to events on some file system. An event service which allows users to subscribe to file system events on remote hosts, can in theory make it possible to subscribe to any digital information available.

The general usage of a remote file system notification service comes from the fact that almost every system or software stores information in the form of files. Files are probably also the most transferred entity on the Internet if we look at systems such as the Web, FTP, CVS and P2P networks. Hence, a file system event notification service can function as a building block for the above systems. In this way, excessive polling can be avoided since events signal when file transfers should occur.

This thesis presents the design and implementation of such an event service. In addition to supporting subscriptions, it allows users to search in the history of file system events.

Our main focus concerning scalability, is making sure that matching of notifications with subscriptions grows slowly as the number of subscriptions is increased. Experiments show that the implemented matcher exhibits sub-linear growth.