Differentiated proxy digital signatures

• US 7,890,762 B2
• Filed: 12/30/2004
• Issued: 02/15/2011
• Est. Priority Date: 12/30/2004
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: SAP AG (SAP SE)
• Inventors: Verlaan, Theo, Dietl, Josef
• Primary Examiner(s): Zand; Kambiz
• Assistant Examiner(s): BAYOU, YONAS A
• Application Number:
  US11/026,559
• Publication Number:
  US 20060156006A1
• Time in Patent Office: 2,238 Days
• Field of Search: 713/176
• US Class Current: 713/176
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures
• CPC Class Codes: H04L 2209/76 Proxy, i.e. using intermediary entity to perform cryptographic operations
• CPC Class Codes: H04L 63/123 received data contents, e.g. message integrity
• CPC Class Codes: H04L 9/3247 involving digital signatures

Abstract

Methods and apparatus, including computer program products, for providing input to a workflow application. Source documents are received that have respective original signatures but no digital signatures. The source documents can be paper documents, or they can be scanned representations of paper documents. Proxy digital signatures are applied to digital representations of the source documents. The proxy digital signatures are differentiated in that they are annotated with metadata indicating the quality of the respective original signatures.

Claims

1. A computer program product for providing input to a workflow application, embodied on non-transitory information carrier, operable to cause a data process apparatus to perform the operations off

receiving source documents, the source documents having respective original signatures but no digital signatures;

and signatures, and wherein the source documents comprise paper documents;

digitizing the source documents to generate digital representations of the source documents, wherein the digital representations of the source documents include the respective original signatures represented digitally but no digital signatures; and

applying differentiated proxy digital signatures to the digital representations of the source documents, the differentiated proxy digital signatures being annotated with metadata indicating the quality of the respective original signatures, the differentiated proxy digital signatures indicating the digital representation of the source documents corresponds to the source documents, and further indicating an actual signature is present on the source documents.

2. The product of claim 1, wherein the digital representations of the source documents comprise text representations.

3. The product of claim 1, wherein the digital representations of the source documents comprise image representations.

4. The product of claim 1, wherein:

the metadata for a particular digital representation indicates whether or not the corresponding source document was a paper document having an original signature that was verified by a person applying the differentiated proxy digital signature to the corresponding source document.

5. The product of claim 1, wherein:

the metadata for a particular digital representation indicates whether or not the corresponding source document was a paper document having an original signature that was not verified by a person applying the differentiated proxy digital signature to the corresponding source document.

6. The product of claim 1, wherein:

the metadata for a particular digital representation indicates whether or not the corresponding source document was a paper document having no original signature.

7. The product of claim 1, further operable to cause a data process apparatus to perform the operation of:

providing the signed digital representations of the source documents with differentiated proxy digital signatures and metadata to a workflow application as input documents.

8. A method, implemented by a data processing system, of providing input to a workflow application, comprising:

receiving a source document having an original signature but no digital signature, and wherein the source document comprises a paper document;

digitizing, by the data processing system, the source document to generate a digital representation of the source document;

document, wherein the digital representation of the source document includes the original signature represented digitally but no digital signature;

assessing, by a user, a correspondence of the digital representation to the source document; and

signing, by the data processing system in response to the assessing by the user, the digital representation with a differentiated proxy digital signature, wherein the differentiated proxy digital signature stands for the correspondence of the digital representation to the source document and to a presence of the original signature on the source document,

wherein the differentiated proxy digital signature does not stand for an authenticity and an integrity of the source document,

wherein the differentiated proxy digital signature is annotated with metadata indicating the quality of the original signature, and

wherein the differentiated proxy digital signature indicates the digital representation corresponds to the source document, and further indicates the original signature is actually present on the source document.

9. The method of claim 8, wherein the digital representation of the source document comprises a text representation.

10. The method of claim 8, wherein the digital representation of the source documents comprises an image representation.

11. The method of claim 8, wherein:

the metadata for the digital representation indicates whether or not the source document was a paper document having the original signature that was verified by the user applying the differentiated proxy digital signature to the source document.

12. The method of claim 8, wherein:

the metadata for the digital representation indicates whether or not the source document was a paper document having the original signature that was not verified by the user applying the differentiated proxy digital signature to the source document.

13. The method of claim 8, wherein:

the metadata for the digital representation indicates whether or not the source document was a paper document having no original signature.

14. The method of claim 8, further comprising:

providing the digital representation signed with the differentiated proxy digital signature and the metadata to the workflow application as input documents.

15. A data processing system that is configured to provide input to a workflow application, comprising:

a digitizer that is configured to receive a source document having an original signature but no digital signature, and that is configured to generate a digital representation of the source document, wherein the source document comprises a paper document, and wherein the digital representation of the source document includes the original signature represented digitally but no digital signature;

a user interface that is configured to receive, from a user, a correspondence of the digital representation to the source document; and

a digital signature generator that is configured to sign, in response to receiving the correspondence, the digital representation with a differentiated proxy digital signature, wherein the differentiated proxy digital signature stands for the correspondence of the digital representation to the source document and to a presence of the original signature on the source document,

wherein the differentiated proxy digital signature does not stand for an authenticity and an integrity of the source document,

wherein the differentiated proxy digital signature is annotated with metadata indicating the quality of the original signature, and

wherein the differentiated proxy digital signature indicates the digital representation corresponds to the source document, and further indicates the original signature is actually present on the source document.

16. The data processing system of claim 15, wherein the digital representations of the source documents comprise text representations.

17. The data processing system of claim 15, wherein the digital representations of the source documents comprise image representations.

18. The data processing system of claim 15, wherein:

the metadata for the digital representation indicates whether or not the source document was a paper document having an original signature that was verified by a person applying the differentiated proxy digital signature to the source document.

19. The data processing system of claim 15, wherein:

the metadata for the digital representation indicates whether or not the source document was a paper document having an original signature that was not verified by a person applying the differentiated proxy digital signature to the source document.

20. The data processing system of claim 15, wherein:

the metadata for the digital representation indicates whether or not the source document was a paper document having no original signature.

21. The data processing system of claim 15, further comprising:

an interface to the workflow application that is configured to provide the digital representation signed with the differentiated proxy digital signature and the metadata to the workflow application as input documents.