An authorization model for a distributed hypertext system

Digital libraries support quick and efficient access to a large number of information sources that are distributed but interlinked. As the amount of information to be shared grows, the need to restrict access only to specific users or for specific usage will surely arise. The protection of information in digital libraries, however, is difficult because of the peculiarity of the hypertext paradigm which is generally used to represent information in digital libraries, together with the fact that related data in a hypertext are often distributed at different sites. We present an authorization model for distributed hypertext systems. Our model supports authorizations at different granularity levels, takes into consideration different types of data and the relationships among them, and allows administrative privileges to be delegated