Statistically private oblivious transfer from cdh

Abstract

Methods for performing oblivious transfer are disclosed. These methods include a method for performing random single bit oblivious transfer (a 'first method'), a method for performing random string oblivious transfer (a “second method”), and a method for performing non-random string oblivious transfer (a “third method”). In the first method, a sender computer can use a hardcore predicate function to obfuscate either a first message or a second message, generating an obfuscated message. The receiver computer can de-obfuscate this obfuscated message to randomly receive either the first message or the second message. The second method and third method can be implemented, with some modification, by repeatedly performing the first method, once for each “message bit” of the sender's messages. In the second and third methods, the receiver computer can send “indicator bits” to the sender computer, enabling the sender computer to transmit a random or non-random message strings to the receiver.