Mobile multi-party digitally signed documents and techniques for using these allowing detection of tamper

摘要

Authenticated base digital document(s) are issued to client(s) by an issuing party, and aggregate digital document(s) are received. An aggregate digital document includes base digital document(s) and attachment(s). Authenticity of the aggregate digital document(s) is verified, resulting in authenticated aggregate digital document(s), which are stored and/or redistributed. Authentication challenge(s) are sent by a verifying party to a client requesting part or all of an aggregate digital document from the client be verified. The part or all of the aggregate digital document is received and authenticity and integrity are verified, resulting in an authenticated aggregate digital document. The client verifies authenticity of a base digital document and receives the authentication challenge(s) for an authenticated aggregate digital document and sends part or all of the authenticated aggregate digital document to the verifying party for verification by the verifying party.