Transparent cosignatures for electronic documents

A major problem facing enterprises communicating via general electronic commercial documents is how to ensure that an incoming document is not only authentic in origin but also was legally authorized within the purported sending enterprise. Another one is how to ensure that only authorized documents leave an enterprise. To quickly identify unauthorized documents, even if authentication of source is correct, this paper proposes transparent cosignature schemes, i.e. signature schemes which require multiple cosigners but which appear to a recipient as the product of one signature process. These will also greatly discourage potential internal fraud, even by several people in collusion. The paper gives a taxonomy and investigates paradigms and properties. An implementation is described