In the m-out-of-n oblivious transfer (OT) model, one party Alice sends n bits to another party Bob, Bob can get only m bits from the n bits. However, Alice cannot know which m bits Bob received. Y. Mu and Naor presented classical m-out-of-n oblivious transfer based on discrete logarithm. As the work of Shor, the discrete logarithm can be solved in polynomial time by quantum computers, so such OTs are unsecure to the quantum computer. In this paper, we construct a quantum m-out-of-n OT (QOT) scheme based on the transmission of polarized light and show that the scheme is robust to general attacks, i.e. the QOT scheme satisfies statistical correctness and statistical privacy.
In the m-out-of-n oblivious transfer (OT) model, one party Alice sends n bits to another party Bob, Bob can get only m bits from the n bits. However, Alice cannot know which m bits Bob received. Y. Mu and Naor presented classical m-out-of-n oblivious transfer based on discrete logarithm. As the work of Shor, the discrete logarithm can be solved in polynomial time by quantum computers, so such OTs are unsecure to the quantum computer. In this paper, we construct a quantum m-out-of-n OT (QOT) scheme based on the transmission of polarized light and show that the scheme is robust to general attacks, i.e. the QOT scheme satisfies statistical correctness and statistical privacy.
In a one-out-of-two oblivious transfer, a party Alice has two messages m 0, m 1 that she sends to another party Bob in such a way that he can decide to obtain either of them at his choosing, but not both. Alice never finds out which message Bob received. First introduced by Wiesner as ‘conjugate coding’, this cryptographic tool was later introduced to the world of public-key cryptography, first by Rabin (in a slightly different form) and then by Even, Goldreich and Lempel who named it after Rabin's primitive, called oblivious transfer. The one-out-of-two oblivious transfer was later shown to be extremely powerful in designing general cryptographic tools. The current paper presents a new design for a one-out-of-two oblivious transfer based on the transmission of polarized light, improving the work of Wiesner and Bennett, Brassard, Breidbart and Wiesner, and shows that the scheme is robust to general attacks.
Oblivious transfer is an interesting cryptographic task in which one party Alice aims to transfer one of her two bits to the other party Bob, with the assurance that he can choose freely his bit, but is not able to obtain the two bits simultaneously. Bob on the other hand wants to be sure that Alice should not be capable of inferring what bit he has chosen. Quantum oblivious transfer (QOT) scheme outperforms its classical counterpart for its higher security and eavesdropping detecting ability. In this paper, we present a new and novel QOT protocol based on tripartite entangled states, which can be proven to be secure against any quantum attacking strategy allowed by physical laws.
Oblivious transfer (OT) is an important tool in cryptography. It serves as a subroutine to other complex procedures of both theoretical and practical significance. A common attribute of OT protocols is that one party (Alice) has to send a message to another party (Bob) and has to stay oblivious to whether Bob did receive the message. Specific (OT) protocols vary by exact definition of the task---in the all-or-nothing protocol, Alice sends a single bit-string message, which Bob is able to read with only 50 probability, whereas in a 1-out-of-2 OT protocol Bob reads one out of two messages sent by Alice. These two flavors of protocol are known to be equivalent. Recently, a computationally secure all-or-nothing OT protocol based on quantum states was developed by A. Souto et al. [Phys. Rev. A 91, 042306 (2015)], which, however, cannot be reduced to a 1-out-of-2 OT protocol by standard means. Here we present an elaborate reduction of this protocol that retains the security of the original.
We propose a quantum protocol for 1-out-of-2, 1-out-of-n and k-out-of-n oblivious transfer. Oblivious transfer is a counter-intuitive cryptographic primitive in which the receiver receives only the information he is authorized for, while the sender does not know what information receiver received. In 1-out-of-2 oblivious transfer, Alice sends two bits to Bob who can choose only one of them to read, while Alice does not know which bit Bob read. k-out-of-n oblivious transfer is an extension of this idea. The proposed protocols do not require any classical communication, are practical, secure and can be implemented using current technology.
In 1-out-of-qOblivious Transfer (OT) protocols, a sender Alice is able to send one ofq≥2messages to a receiver Bob, all while being oblivious to which message was transferred. Moreover, the receiver learns only one of these messages. Oblivious Transfer combiners takeninstances of OT protocols as input, and produce an OT protocol that is secure if sufficiently many of thenoriginal OT instances are secure. We present new 1-out-of-qOT combiners that are perfectly secure against active adversaries. Our combiners arise from secret sharing techniques. We show that given anFq-linear secret sharing scheme on a set ofnparticipants and adversary structureA, we can construct ann-server, 1-out-of-qOT combiner that is secure against an adversary corrupting either Alice and a set of servers inA, or Bob and a set of serversBwithBˉ∈/A. If the normalized total share size of the scheme is$\ell ,thentheresultingOTcombinerrequires\ell callstoOTprotocols,andthetotalamountofbitsexchangedduringtheprotocolis(q^{2}+q+1)\ell \log q.Wealsopresentaconstructionbasedon1−out−of−2OTcombinersthatusestheprotocolofCreˊpeau,BrassardandRobert(FOCS1986).Thisconstructionprovidessmallercommunicationcostsforcertainadversarystructures,suchasthresholdones:Foranyprimepowerq\geq n,therearen−server,1−out−of−qOTcombinersthatareperfectlysecureagainstactiveadversariescorruptingeitherAliceorBob,andaminorityoftheOTcandidates,exchangingO(qn\log q)$bits in total.
In cryptography, oblivious transfer (OT) is an important multi-party cryptographic primitive and protocol, that is suitable for many upper-layer applications, such as secure computation, remote coin-flipping, electrical contract signing and exchanging secrets simultaneously. However, some no-go theorems have been established, indicating that one-out-of-two quantum oblivious transfer (QOT) protocols with unconditional security are impossible. Fortunately, some one-out-of-two QOT protocols using the concept of Crépeau’s reduction have been demonstrated not to conform to Lo’s no-go theorem, but these protocols require more quantum resources to generate classical keys using all-or-nothing QOT to construct one-out-of-two QOT. This paper proposes a novel and efficient one-out-of-two QOT which uses quantum resources directly instead of wasting unnecessary resources to generate classical keys. The proposed protocol is not covered by Lo’s no-go theorem, and it is able to check the sender’s loyalty and avoid the attack from the receiver. Moreover, the entangled state of the proposed protocol is reusable, so it can provide more services for the participants when necessary. Compared with other QOT protocols, the proposed protocol is more secure, efficient, and flexible, which not only can prevent external and internal attacks, but also reduce the required resources and resource distribution time.