Abstract: A content-based authorization method is described, wherein the method is operable to validate that a user has access to certain content. By having access to the content, the system is able to decide that the user is authorized to access the content, and may perform operations or set access rights accordingly.

Abstract: A content-based authorisation method is described, wherein the method is operable to validate that a user has access to certain content. By having access to the content, the system is able to decide that the user is authorised to access the content, and may perform operations or set access rights accordingly.

Abstract: A digital object for distribution from a provider to a content user and a method of distribution of such an object is disclosed. The digital object comprises content and a tag containing data that is derived algorithmically from the content and from a secret not known to the content user. The tag is constructed such that the content user can, upon receipt of a communication from a requestor purporting to have the authority of the provider, perform an exchange of information with the requestor, and by inspection of the exchanged information and of the tag, determine whether the requestor is in possession of the secret and choose to act upon or not act upon the communication accordingly. The tag may additionally include a value that defines an access category that specifies the extent to which the owner wishes the content to be distributed.