Visa Inc.
SECURE MULTI-PARTY RANDOM BIT GENERATION

Abstract:

Methods and systems for secure multi-party generation of random bits are disclosed. These random bits can be generated securely, even if some parties (i.e., less than a corruption threshold) are dishonest or malicious. Methods and systems can use secure environments in order to securely generate and store cryptographic keys. Using broadcast protocols such as Dolev-Strong, a generator computer can distribute a public protocol instance key to other participant computers. Each participant computer can generate a random bit and encrypted the random bit with the public protocol instance key, and broadcast its encrypted random bit to the other participant computers. Once each participant computer has received the encrypted random bits from all other participant computers, the private protocol instance key can be released to the participant computers, enabling the participant computers to decrypt the encrypted random bits, and calculate an output random bit based on the encrypted random bits.