Algebra Operations of Information Resource View in Internet Environment

Abstract

In an open network environment, information resource could be modified, divided and integrated while transmitting. This would result in that origins of different sections within an information resource are different. Users cannot trace the path of the information resource’s propagation, so they are unable to determine its reliability. To resolve this security problem, a new concept “Information Resource View” is proposed which uses “File View” as reference. Each information resource is divided into logical blocks. Several logical blocks are combined as one view through the multi-layers mapping mechanism. In order to provide the operation interface to manipulate information resource views, this paper proposes nine kinds of algebra operations using the relation algebra operations of database as reference. There are four kinds of relation algebra operations of database which are taken as basic operations, they are union, selection, difference and rename. Then, this paper defines information resource life-cycles as two main phases: creating the information resource view and accessing the content of it. Finally, according the requirements of these two phases, it defines other five kinds of relation algebra operations: normalization, citation, projection, instantiation and access.