Computer implemented method for sending a message to a recipient user, receiving a message by a recipient user, a computer readable storage medium and a computer system

• US 8,677,146 B2
• Filed: 11/03/2010
• Issued: 03/18/2014
• Est. Priority Date: 12/18/2009
• Status: Active Grant

• Current Assignee: Adrian Spalka, CompuGroup Medical SE
• Original Assignee: Compugroup Medical AG (CompuGroup Medical SE & Co. KGaA)
• Inventors: Spalka, Adrian, Lehnhardt, Jan
• Primary Examiner(s): Le, Vu
• Assistant Examiner(s): Mangialaschi, Tracy
• Application Number:
  US12/904,359
• Publication Number:
  US 20110154044A1
• Time in Patent Office: 1,231 Days
• Field of Search: 713/168, 713/176
• US Class Current: 713/189
• CPC Class Codes: H04L 2209/08 Randomization, e.g. dummy operations or using noise
• CPC Class Codes: H04L 2209/42 Anonymization, e.g. involving pseudonyms
• CPC Class Codes: H04L 2209/88 Medical equipments
• 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 9/3066 involving algebraic varieties, e.g. elliptic or hyper-elliptic curves

Abstract

The invention relates to a computer implemented method for sending a message to a recipient user, wherein a recipient asymmetric cryptographic key pair is associated with the recipient user, said key pair comprising a public recipient key and a private recipient key, the method comprising sending the message to said recipient user with the recipient address to which the message is sent comprising the public recipient key.

Claims

1. A computer implemented method for sending a message to a recipient user, the method comprising the following steps performed by a processor:

generating a public key and a private key, the public key and private key forming an asymmetric cryptographic key pair, via the following steps;

receiving a user-selected secret,

storing the user-selected secret in memory associated with the processor,

computing the private key by applying a function to the user-selected secret,

storing the private key in memory,

computing the public key using the private key,

generating a recipient address of a user based upon the public key, comprising using the public key as the recipient address or as a portion of the recipient address, and

sending the message to the user using the recipient address.

2. The method of claim 1, wherein said message is sent encrypted with the public key to the user.

3. The method of claim 1, wherein said message is sent from a sender user, wherein a sender asymmetric cryptographic key pair is associated with the sender user, said key pair comprising a public sender key and a private sender key, the method further comprising the steps of

generating a signature of the message using the private sender key, and

sending the signature to said user as well as the sender'"'"'s public key for signature verification.

4. The method of claim 1, wherein the message is a synchronous or asynchronous conferencing message.

5. The method of claim 4, wherein the message is an email message with the message being sent to the user by email, wherein the email address comprises the public key.

6. The method of claim 1, wherein the computation of the public key is performed by elliptic curve cryptography (ECC).

7. The method of claim 5, further comprising registering the public key as an email address of the user.

8. The method of claim 7, further comprising:

registering the public key in a public key infrastructure (PKI) under a pseudonym of the user,

providing the pseudonym to another party, and

obtaining the public key from the PKI by the other party by use of the pseudonym, wherein the sending comprises emailing the message by the other party to the user using the public key as the recipient address.

9. The method of claim 1, further comprising:

storing data of the user in a publicly accessible database in an unencrypted form, and

retrieving the data from the publicly accessible database using the public key as a database access key.

10. The method of claim 1, whereby the identity of the user is not revealed when sending the message to the user.

11. The method of claim 1, wherein the applying comprises applying an embedding and randomizing function to the user-selected secret.

12. The method of claim 11, wherein the applying the embedding and randomizing function comprises:

applying a first one-way function to the user-selected secret to provide a first value,

providing a random number,

embedding the random number and the first value by combining them to provide a combination, and

applying a second one-way function to the combination to provide a second value, wherein the second value constitutes the private key.

13. The method of claim 12, wherein at least one of the first one-way function and the second one-way function comprises point multiplication along an elliptic curve.

14. The method of claim 11, further comprising:

storing a parameter to represent a random number generated by the embedding and randomizing function; and

using the parameter to regenerate the public key.

15. The method of claim 1, wherein the sending comprises sending the message unencrypted.

16. The method of claim 1, further comprising erasing the user-selected secret and the private key from the memory directly after computing the public key.

17. A computer system for sending a message to a recipient user, the system comprising:

one or more input devices for entering a user-selected secret,

memory for storing the user-selected secret and a private key,

a recipient asymmetric cryptographic key pair which is associated with the recipient user, said key pair comprising a public key and the private key,

a processing unit that;

computes the private key by applying a function to the user-selected secret,

computes the public key using the private key,

generates a recipient address of the recipient user based upon the public key, comprising using the public key as the recipient address or as a portion of the recipient address,

an interface that sends the message to said recipient user using the recipient address,

a first messaging service that sends messages, and

a second messaging service that receives messages sent by the first messaging service.

18. A computer program product comprising a non-transitory computer-readable medium comprising computer-executable instructions that when executed cause a processor to:

generate a public key and a private key, the public key and private key forming an asymmetric cryptographic key pair, via the following steps;

receive a user-selected secret,

store the user-selected secret in memory associated with the processor,

compute the private key by applying a function to the user-selected secret,

store the private key in memory,

compute the public key using the private key,

generate a recipient address of a user based upon the public key, comprising using the public key as the recipient address or as a portion of the recipient address, and

send the message to the user using the recipient address.

19. The computer program product of claim 18, wherein the instructions further comprise instructions to register the public key as an email address of the user.

20. The computer program product of claim 18, wherein the instructions further comprise instructions to:

store data of the user in a publicly accessible database in an unencrypted form, and

retrieve the data from the publicly accessible database using the public key as a database access key.