Efficient methods for authenticated communication

Patent metadata

Field	Value
Publication number	US-11394697-B2
Application number	US-201916694668-A
Country	US
Kind code	B2
Filing date	Nov 25, 2019
Priority date	Jun 18, 2014
Publication date	Jul 19, 2022
Grant date	Jul 19, 2022

Abstract

Embodiments of the invention relate to efficient methods for authenticated communication. In one embodiment, a first computing device can generate a key pair comprising a public key and a private key. The first computing device can generate a first shared secret using the private key and a static second device public key. The first computing device can encrypt request data using the first shared secret to obtain encrypted request data. The first computing device can send a request message including the encrypted request data and the public key to a server computer. Upon receiving a response message from the server computer, the first computing device can determine a second shared secret using the private key and the blinded static second device public key. The first computing device can then decrypt the encrypted response data from the response message to obtain response data.

First claim

What is claimed is:

1. A system comprising a first computing device for communicating with a second computing device that generates a blinded static second device public key by applying a cryptographic nonce to a static second device public key, the first computing device comprising:
a processor;
a memory; and
a non-transitory computer-readable storage medium comprising instructions stored thereon, that, when executed on the processor, cause the processor to perform:
obtaining and storing, the static second device public key in the memory;
determining to communicate with the second computing device;
based on the determining, retrieving the static second device public key from the memory;
determining a key pair comprising a public key and a private key;
generating a first shared secret using the private key and the static second device public key;
receiving request data;
obtaining encrypted request data by encrypting the request data using the first shared secret;
sending a request message including the encrypted request data and the public key to the second computing device;
receiving a response message including encrypted response data and the blinded static second device public key from the second computing device, wherein response data of the encrypted response data includes the cryptographic nonce;
determining a second shared secret using the private key and the blinded static second device public key, wherein the second shared secret is different from the first shared secret;
obtaining the response data by decrypting the encrypted response data using the second shared secret, wherein the response data includes a payment credential; and
conducting a payment transaction using the payment credential.

2. The system of claim 1 , wherein the request data includes identification data corresponding to the first computing device or a user.

3. The system of claim 1 , wherein the public key is a combined ephemeral public key, wherein the private key is a combined ephemeral private key, and wherein the instructions, when executed on the processor, further perform:
determining the combined ephemeral public key and the combined ephemeral private key using an identification factor generated using identification data and authentication data.

4. The system of claim 1 , wherein the public key is a first device public key, wherein the private key is a first device private key, wherein the request data includes a first device certificate comprising a static first device public key, wherein the response message further includes a second device public key, and wherein the instructions, when executed on the processor, further perform:
generating an auxiliary shared secret using the second device public key and a static first device private key corresponding to the static first device public key, wherein decrypting the encrypted response data also uses the auxiliary shared secret.

5. The system of claim 1 , wherein the instructions, when executed on the processor, further perform:
generating another shared secret and another blinded static second device public key using the second shared secret; and
associating the another blinded static second device public key with the another shared secret, wherein the another shared secret is used to decrypt subsequent encrypted response data received from the second computing device.

6. The system of claim 1 , wherein the response data includes a second device certificate comprising the static second device public key, and wherein the instructions, when executed on the processor, further perform:
validating the second device certificate;
generating a second device session identifier using the static second device public key and the cryptographic nonce; and
comparing the second device session identifier with the blinded static second device public key received from the second computing device, wherein the second computing device is authenticated if the second device session identifier matches the blinded static second device public key.

7. The system of claim 1 further comprising:
the second computing device, wherein the second computing device is configured to:
receive, from the first computing device, the request message;
generate the first shared secret using the public key and a static second device private key;
decrypt the encrypted request data using the first shared secret to obtain the request data;
blind the static second device private key to determine a blinded static second device private key;
generate the second shared secret using the blinded static second device private key and the public key;
obtain the encrypted response data by encrypting the response data using the second shared secret; and
send, to the first computing device, the response message.

8. A computer-implemented method for a first computing device for communicating with a second computing device that generates a blinded static second device public key by applying a cryptographic nonce to a static second device public key, the method comprising:
obtaining and storing, by the first computing device, the static second device public key in a memory;
determining, by the first computing device, to communicate with the second computing device;
based on the determining, retrieving, by the first computing device, the static second device public key from the memory;
determining, by the first computing device, a key pair comprising a public key and a private key;
generating, by the first computing device, a first shared secret using the private key and the static second device public key;
receiving, by the first computing device, request data;
obtaining, by the first computing device, encrypted request data by encrypting the request data using the first shared secret;
sending, by the first computing device, a request message including the encrypted request data and the public key to the second computing device;
receiving, by the first computing device, a response message including encrypted response data and the blinded static second device public key from the second computing device, wherein response data of the encrypted response data includes the cryptographic nonce;
determining, by the first computing device, a second shared secret using the private key and the blinded static second device public key, wherein the second shared secret is different from the first shared secret;
obtaining, by the first computing device, the response data by decrypting the encrypted response data using the second shared secret, wherein the response data includes a payment credential; and
conducting, by the first computing device, a payment transaction using the payment credential.

9. The computer-implemented method of claim 8 , wherein the request data includes identification data corresponding to the first computing device or a user.

10. The computer-implemented method of claim 8 , wherein the public key is a combined ephemeral public key, wherein the private key is a combined ephemeral private key, the method further comprising:
determining, by the first computing device, the combined ephemeral public key and the combined ephemeral private key using an identification factor generated using identification data and authentication data.

11. The computer-implemented method of claim 8 , wherein the public key is a first device public key, wherein the private key is a first device private key, wherein the request data includes a first device certificate comprising a static first device public key, wherein the response message further includes a second device public key, the method further comprising:
generating, by the first computing device, an auxiliary shared secr

Assignees

• Visa Int Service Ass

Inventors

• Le Saint Eric
• Mardikar Upendra
• Fedronic Dominique

Classifications

• G06Q20/3227 Primary

  using secure elements embedded in M-devices · CPC title

• H04L9/0841

  involving Diffie-Hellman or related key agreement protocols · CPC title

• G06Q20/3829

  involving key management · CPC title

• H04L2463/061

  applying further key derivation, e.g. deriving traffic keys from a pair-wise master key · CPC title

• H04L63/0442 Primary

  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 title