Quantum Oblivious Transfer and Its Application
Date Issued
2006
Date
2006
Author(s)
Ko, Chien-Ming
DOI
en-US
Abstract
Oblivious transfer, a special communication protocol, is widely used in various
variants of security issue or cryptographic application such as Contrast Signing,
Secrets Exchange, Coin Flipping and so on. Oblivious transfer allows a party
to sent two messages to the receiver who can choose one of them and learn it,
remaining ignorant about the other, while the sender who has no ideal about
what the receiver choice. In other words, this is a protocol by which a sender
sends some information to the receiver, but remains oblivious as to what is sent.
Oblivious transfer has been developed in many different forms since it was
introduced in 1981 by Michael O. Robin. The so-called Robin’s oblivious transfer
means: sender sends information to receiver with probability 1/2, while the
sender is not sure whether the receiver obtain it or not. And the form mentioned
above, a more useful one, is called 1-2 oblivious transfer or 1-out-of-2
oblivious transfer. Besides, string and bit oblivious transfer is discussed in detail
for implementation. All of these forms have been used in various problems of
cryptography and implementation by mathematical method
Nevertheless, mathematical method such as RSA scheme, which is based on
difficult mathematical problem, is a conditional secure way. We can use quantum
method to defeat these systems and it will not be secure any more. Therefore,
we try to resolve this issue by quantum way. Popescu and Rohrlich have provided
a ”non-locality machine” or ”PR machine,” which can realize oblivious transfer
and we can build PR machine by quantum entanglement.
This quantum oblivious transfer system, mentioned above, can be used in many applications. We present a contract signing protocol based on our system,
quantum oblivious transfer, and discuss the security of this system.
Subjects
量子
密碼學
模糊傳輸
電子合約
Quantum
Cryptography
Oblivious Transfer
Electronic Contract
Type
thesis