Methods and device for digitally signing data

• US 20060005028A1
• Filed: 06/22/2005
• Published: 01/05/2006
• Est. Priority Date: 08/27/2000
• Status: Active Grant

• Current Assignee: Cidway Technologies, Ltd.
• Original Assignee: Cidway Technologies, Ltd.
• Inventors: Labaton, Isaac J.
• Granted Patent: US 7,181,621 B2
• Time in Patent Office: Days
• US Class Current: 713/176
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 2209/80 Wireless network architectures or network communication protocols for wireless network security H04W12/00
• CPC Class Codes: H04L 63/0442 wherein the sending and receiving network entities apply asymmetric encryption, i.e. different keys for encryption and decryption cryptographic mechanisms or cryptographic arrangements for public-key encryption H04L9/30
• CPC Class Codes: H04L 63/062 for key distribution, e.g. centrally by trusted party cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819
• CPC Class Codes: H04L 63/123 received data contents, e.g. message integrity
• CPC Class Codes: H04L 9/3234 involving additional secure or trusted devices, e.g. TPM, smartcard, USB or software token network architectures or network communication protocols for supporting authentication of entities using an additional device in a packet data network H04L63/0853
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04L 9/3263 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L63/0823

Abstract

Methods and device for digitally signing documents by using a portable device that encodes a signature string to sound. The acoustic signature string may be transmitted and then decoded back into digital data. The signature string may be further processed to verify the signature of the document and to produce a certificate of identity and integrity for the document. The certificate of identity and integrity may be used to further identify and validate the document and its signer.

Claims

1-21. -21. (canceled)

22. A method for verifying a digital signature on a document utilizing a third party node, comprising the steps of:

digitally signing, by a signer node, the document wherein the digital signature of the document is created;

extracting, by the signer node, the document from the digital signature;

calculating a hash value of the document;

creating a modified digital string by replacing the extracted document with the calculated hash value;

sending, by the signer node, the modified digital string to the third party node; and

mathematically verifying, by the third party node, that the modified digital string includes the hash value of the document which has been digitally signed by a signer.

23. The method of claim 22, further comprising the steps of:

preparing, by the third party node, a new digital string that includes the hash value of the document, and an indication that the verification of the digital signature was successful, wherein the indication includes an identity of the signer;

signing the new digital string with a third party private key; and

transmitting the digitally signed new string to the signer node.

24. The method of claim 23, wherein the indication further includes a time of the verification.

25. A method for verification of a digital signature of a document, generated by a signer node, by a recipient of the digital signature, utilizing a third party node, comprising the steps of:

extracting the document, by a recipient node, from a digital string that includes the digital signature;

replacing the extracted document by a hash value of the document, wherein a modified digital string is created;

sending the modified string to the third party node; and

mathematically verifying, by the third party node, that the modified digital string contains the hash value of the document which has been digitally signed by a signer.

26. The method of claim 25, further comprising the steps of:

preparing, by the third party node, a new digital string including the hash value of the document, and an indication that the verification of the digital signature was successful, wherein the indication includes an identity of the signer;

signing the new string with a third party private key; and

transmitting the digitally signed new string to the recipient node.

27. The method of claim 26, wherein the indication further comprises a time of the verification.