Visa International Service Association

Leland Stanford Junior University

Shashank Agrawal

Payman Mohassel

Pratyay Mukherjee

Saikrishna Badrinarayanan

Gaven James Watson

Atul Luykx

Eric Fernand Le Saint

Mihai Christodorescu

Dan Boneh

Mahdi Zamani

Peter Rindal

Srinivasan Raghuraman

Maliheh Shirvanian

Peihan Miao

Wei Dai

Chaya Ganesh

Karl Benedikt Bünz

Kim R Wagner

Sunpreet Singh Arora

Mastooreh Salajegheh

Eric Le Saint

Dmitri Bannikov

Yilei Chen

Sergey Smirnoff

Karl Benedikt Bunz

Estuardo Alpirez Bock

Selvaganesh Vasudevan

Systems, methods, and computer readable media are provided for improving the usability of a cryptogram generated in a first cryptographic protocol such as triple-DES. The methods may generate a first cryptogram using a first identifier in a first cryptographic protocol, stored in a key store within an insecure memory of the mobile communication device, generate, within a secure memory of the mobile communication device, a second cryptogram using a second identifier in a second cryptographic protocol, stored in the secure memory, combining, the first cryptogram and a number of characters of the second cryptogram equal to the length of the first cryptogram to generate a third cryptogram and transmitting the third cryptogram to an payment processing network to validate a transaction. A transaction associated with the third cryptogram may be validated by an authorization entity or an issue entity.

Mobile payments using multiple cryptographic protocols

Systems, methods, and apparatuses of using biometric information to authenticate a first device of a user to a second device are described herein. A method includes storing, by the first device, a first key share of a private key and a first template share of a biometric template of the user. The second device stores a public key, and one or more other devices of the user store other key shares and other template shares. The first device receives a challenge message from the second device, measures biometric features of the user to obtain a measurement vector, and sends the measurement vector and the challenge message to the other devices. The first device receives partial computations, generated using a respective template share, key share, and the challenge message, from the other devices, uses them to generate a signature of the challenge message and send the signature to the second device.

Leveraging multiple devices to enhance security of biometric authentication

A method is disclosed. The method includes receiving, by a user device, an encrypted message from a server computer. The encrypted message is a message encrypted with a master secret key or a key derived from the master secret key. The user device signs the encrypted message with a secure element private key. The user device, using a whitebox, cryptographically recovers a secure element public key from a certified key using a server computer public key. The certified key is certified by the server computer and based on at least the secure element public key. The user device, using the whitebox, cryptographically recovers the encrypted message from the signed encrypted message using the secure element public key. The user device, using the whitebox, decrypts the encrypted message using the master secret key or the key derived from the master secret key in the whitebox to obtain the message.

Systems and methods for whitebox device binding

A method includes a validation computer receiving an authorization request message comprising a user state and a user proof from a user device. The user state comprises first and second user state elements. The user proof comprises first, second, and third user proof elements. The validation computer computes a first verification value by multiplying the first user proof element raised to the power of the second user state element, and the second user proof element raised to the power of the first user state element. The computer computes a second verification value by raising the second user proof element to the power of the second user state element. The computer compares the first verification value to a first accumulated state element of an accumulated state. The compares the second verification value to a second accumulated state element. The validation computer authorizes the authorization request message based on the comparison steps.

Key-value map commitments system and method

At an authorization server, a shared secret electronic key may be shared with a second computer. A selection to use a system to complete a transaction may be received from a first computing device. An image may be communicated to the first computing device. A digital representation entered by the user representing the image and a PIN based on the copy of the shared electronic key may be received from the second computing device. The system and method may determine if the digital representation entered by the user on the second computing device matches the image communicated to the first computing device. The system and method may determine if the PIN based on the copy of the shared electronic key from the second computing device is as expected. In response to determining the digital representation entered by the user matches the image and the PIN the second computing device is as expected, the user may be authorized.

Second factor for secure password authentication

Disclosed is a method, system, and computer program product for determining solvency of a digital asset exchange system. The method includes identifying a plurality of blockchain addresses corresponding to a plurality of users of a digital asset exchange system, generating a first commitment to an amount of digital assets corresponding to the plurality of blockchain addresses, and generating a second commitment to a balance of each user of the plurality of users. The method also includes generating a first component of a zero-knowledge algorithm that is configured to receive, as input, the first commitment. The method further includes generating, with at least one processor, a second component of the zero-knowledge algorithm that is configured to receive, as input, the second commitment. The method further includes determining that the digital asset exchange system is solvent based on the zero-knowledge algorithm.

Method, system, and computer program product for determining solvency of a digital asset exchange

Techniques of authenticating a first device of a user to a second device are disclosed. The method enables the second device to perform authentication using a biometric template stored on the first device and a biometric measurement. Homomorphic encryption may be used by the first device to encrypt the biometric template and the second device to determine an encrypted similarity metric between the biometric template and the biometric measurement. The second device can also determine an encrypted code using an authentication function and the encrypted similarity metric. The second device sends the encrypted code and the encrypted similarity metric to be decrypted by the first device. The second device can receive a response from the first device, indicating whether a decrypted similarity metric exceeds a threshold; and whether the decrypted code matches a test code. The second device can then authenticate the user based on the response.

Privacy preserving biometric authentication

Systems and methods for threshold authenticated encryption are provided. A collection of cryptographic devices may encrypt or decrypt a message, provided that a threshold number of those devices participate in the encryption process. One cryptographic device may generate a commitment message and transmit it to the other selected devices. Those devices may each perform a partial computation using the commitment message, and transmit the partial computations back to the encrypting or decrypting device. The encrypting or decrypting device may use those partial computations to produce a cryptographic key, which may then be used to encrypt or decrypt the message.

Multi-party threshold authenticated encryption

Methods and systems for privacy-preserving identity attribute verification are presented. During an interaction between a relying entity and a user, a relying entity computer can transmit a policy token to a user device. The policy token may indicate the information needed by the relying entity in order to perform the interaction. The user device can verify the policy token, then use the policy token in conjunction with an identity token to generate a zero-knowledge proof. The user device may transmit the zero-knowledge proof to an identity service provider computer. The identity service provider computer may verify the zero-knowledge proof, then generate a verification message. The identity service provider computer may sign the verification message and transmit the signed verification message to the relying entity computer. The relying entity computer may verify the verification message and complete the interaction with the user.

Privacy-preserving identity attribute verification using policy tokens

An initiator device can broadcast a witness request to one or more authentication devices. The one or more authentication devices can then determine an assurance level from a range of assurance levels and determine a token share corresponding to the assurance level. The initiator device can then receive, from the one or more authentication devices, at least one witness response comprising the token share corresponding to the assurance level. The initiator device can generate an authentication token using a set of token shares. The initiator device can then transmit the authentication token to an authentication server, wherein the authentication server verifies the authentication token.

Collaborative risk aware authentication

Blockchain-based, smart contract platforms have great promise to remove trust and add transparency to distributed applications. However, this benefit often comes at the cost of greatly reduced privacy. Techniques for implementing a privacy-preserving smart contract is described. The system can keep accounts private while not losing functionality and with only a limited performance overhead. This is achieved by building a confidential and anonymous token on top of a cryptocurrency. Multiple complex applications can also be built using the smart contract system.

Blockchain system for confidential and anonymous smart contracts

Systems and methods for improved distributed symmetric cryptography are disclosed. A client computer may communicate with a number of cryptographic devices in order to encrypt or decrypt data. Each cryptographic device may possess a secret share and a verification share, which may be used in the process of encrypting or decrypting data. The client computer may generate a commitment and transmit the commitment to the cryptographic devices. Each cryptographic device may generate a partial computation based on the commitment and their respective secret share, and likewise generate a partial signature based on the commitment and their respective verification share. The partial computations and partial signatures may be transmitted to the client computer. The client computer may use the partial computations and partial signatures to generate a cryptographic key and verification signature respectively. The client computer may use the cryptographic key to encrypt or decrypt a message.

Distributed symmetric encryption

Embodiments disclosed herein are directed to methods and systems of password-based threshold authentication, which distributes the role of an authentication server among multiple servers. Any t servers can collectively verify passwords and generate authentication tokens, while no t&#x2212;1 servers can forge a valid token or mount offline dictionary attacks.

Password based threshold token generation

Disclosed is a system, method, and computer program product for determining solvency of a digital asset exchange system. The method includes identifying a plurality of blockchain addresses corresponding to a plurality of users of the digital asset exchange system, generating a first commitment to an amount of digital assets corresponding to the plurality of blockchain addresses, generating a second commitment to a balance of each user of the plurality of users, generating a first component of a zero-knowledge algorithm configured to receive, as input, the first commitment, and to output a value generated based on each public key, generating a second component of the zero-knowledge algorithm configured to receive, as input, the second commitment, and to output a value generated based on each user balance, and determining, with at least one processor, that the digital asset exchange system is solvent based on the zero-knowledge algorithm.

Growing community of inventors

Sunnyvale, CA, United States of America

Shashank Agrawal