169,654 research outputs found
Orthogonal-state-based protocols of quantum key agreement
Two orthogonal-state-based protocols of quantum key agreement (QKA) are
proposed. The first protocol of QKA proposed here is designed for two-party
QKA, whereas the second protocol is designed for multi-party QKA. Security of
these orthogonal-state-based protocols arise from monogamy of entanglement.
This is in contrast to the existing protocols of QKA where security arises from
the use of non-orthogonal state (non-commutativity principle). Further, it is
shown that all the quantum systems that are useful for implementation of
quantum dialogue and most of the protocols of secure direct quantum
communication can be modified to implement protocols of QKA.Comment: 9 pages, no figur
A look ahead approach to secure multi-party protocols
Secure multi-party protocols have been proposed to enable non-colluding parties to cooperate without a trusted server. Even though such protocols prevent information disclosure other than the objective function, they are quite costly
in computation and communication. Therefore, the high overhead makes it necessary for parties to estimate the utility that can be achieved as a result of the protocol beforehand. In this paper, we propose a look ahead approach, specifically for secure multi-party protocols to achieve distributed
k-anonymity, which helps parties to decide if the utility benefit from the protocol is within an acceptable range before initiating the protocol. Look ahead operation is highly localized and its accuracy depends on the amount of information the parties are willing to share. Experimental results show
the effectiveness of the proposed methods
A Formal Framework For Multi-Party Business Protocols (Revision of CentER DP 2008-79)
Enterprise-class information systems based on the principles of Service Oriented Architecture comprise large numbers of long-running, highly dynamic complex end-to-end service interactions, called conversations, based on message exchanges that typically transcend several organizations and span several geographical locations. Conversations in service-based systems can be described using business protocols that are formal notations specifying the timed message exchanges among participants in a conversation from a local point of view (orchestrations) or global (choreographies). In this work we introduce a formal framework based on Deterministic Finite Automata enriched with temporal constraints to describe multi-party business protocols. We also explore the notion of multi-party business protocol soundness and show how it is possible to execute a multi-party protocol consistently in a completely distributed manner and at the same time ensure the progression of the execution (i.e. no ādeadlocksā).service oriented architecture;message exchange patterns business protocols;orchestrations;choreographies;soundness
Recommended from our members
Unconditionally secure relativistic multi-party biased coin flipping and die rolling.
We introduce relativistic multi-party biased die-rolling protocols, generalizing coin flipping to M ā„ 2 parties and to N ā„ 2 outcomes for any chosen outcome biases and show them unconditionally secure. Our results prove that the most general random secure multi-party computation, where all parties receive the output and there is no secret input by any party, can be implemented with unconditional security. Our protocols extend Kent's (Kent A. 1999 Phys. Rev. Lett. 83, 5382) two-party unbiased coin-flipping protocol, do not require any quantum communication, are practical to implement with current technology and to our knowledge are the first multi-party relativistic cryptographic protocols
A proposal for founding mistrustful quantum cryptography on coin tossing
A significant branch of classical cryptography deals with the problems which
arise when mistrustful parties need to generate, process or exchange
information. As Kilian showed a while ago, mistrustful classical cryptography
can be founded on a single protocol, oblivious transfer, from which general
secure multi-party computations can be built.
The scope of mistrustful quantum cryptography is limited by no-go theorems,
which rule out, inter alia, unconditionally secure quantum protocols for
oblivious transfer or general secure two-party computations. These theorems
apply even to protocols which take relativistic signalling constraints into
account. The best that can be hoped for, in general, are quantum protocols
computationally secure against quantum attack. I describe here a method for
building a classically certified bit commitment, and hence every other
mistrustful cryptographic task, from a secure coin tossing protocol. No
security proof is attempted, but I sketch reasons why these protocols might
resist quantum computational attack.Comment: Title altered in deference to Physical Review's fear of question
marks. Published version; references update
Universally Composable Quantum Multi-Party Computation
The Universal Composability model (UC) by Canetti (FOCS 2001) allows for
secure composition of arbitrary protocols. We present a quantum version of the
UC model which enjoys the same compositionality guarantees. We prove that in
this model statistically secure oblivious transfer protocols can be constructed
from commitments. Furthermore, we show that every statistically classically UC
secure protocol is also statistically quantum UC secure. Such implications are
not known for other quantum security definitions. As a corollary, we get that
quantum UC secure protocols for general multi-party computation can be
constructed from commitments
- ā¦