Patent ID: 7591007

Claim:
A computer network comprising: a computer server device comprising at least one information source; an Access Control List (ACL) for said information source, listing authorized users of said information source together with their access privileges; and means for generating a reference to said information source; means for adding access privileges to said reference; means for passing the resulting enhanced reference to another user of the network and, thus, providing said with the access privileges passed; means for automatically generating a Reference Passing Tree (RPT) for said information source by automatically storing the identification of a user sending said enhanced reference in a storage device, the identification of the another user receiving said enhanced reference and the access privileges provided by said enhanced reference; and means for “cupping” said RPT, thus, automatically revoking at least parts of the another user's access privileges, which have been provided directly or indirectly by said user, when said parts of said user's access privileges are revoked.