Disclosed is an apparatus for producing a resource descriptor for a particular resource having an associated URI, including a controller forming one or more candidate signatures for the particular resource wherein said controller identifies one of said candidate signatures having a predetermined level of correspondence to the particular resource as a signature for the particular resource; and a concatenator for merging the signature with the URI to produce the resource descriptor. A method, and computer program product having executable instructions for implementing the method, includes forming one or more candidate signatures for the particular resource wherein one of said candidate signatures having a predetermined level of correspondence to the particular resource is identified as a signature for the particular resource; and concatenating the signature with the URI to produce the resource descriptor.