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[en] Private queries allow a user, Alice, to learn an element of a database held by a provider, Bob, without revealing which element she is interested in, while limiting her information about the other elements. We propose to implement private queries based on a quantum-key-distribution protocol, with changes only in the classical postprocessing of the key. This approach makes our scheme both easy to implement and loss tolerant. While unconditionally secure private queries are known to be impossible, we argue that an interesting degree of security can be achieved by relying on fundamental physical principles instead of unverifiable security assumptions in order to protect both the user and the database. We think that the scope exists for such practical private queries to become another remarkable application of quantum information in the footsteps of quantum key distribution.
[en] In this article we present a general security strategy for quantum secret sharing (QSS) protocols based on the scheme presented by Hillery, Buzek, and Berthiaume (HBB) [Phys. Rev. A 59, 1829 (1999)]. We focus on a generalization of the HBB protocol to n communication parties thus including n-partite Greenberger-Horne-Zeilinger states. We show that the multipartite version of the HBB scheme is insecure in certain settings and impractical when going to large n. To provide security for such QSS schemes in general we use the framework presented by some of the authors [M. Huber, F. Mintert, A. Gabriel, B. C. Hiesmayr, Phys. Rev. Lett. 104, 210501 (2010)] to detect certain genuine n-partite entanglement between the communication parties. In particular, we present a simple inequality which tests the security.
[en] This Act governing State security in the nuclear field lays down that the King may determine the security measures to be complied with concerning nuclear research, materials, methods of production used by establishments and legal or physical persons having in their possession information, documents or material obtained either directly from the Government or with its consent. The Act was supplemented by Royal Order of 14 March 1956 which amplified its provisions by laying down specific requirements regarding the classification of information and material, the security measures to be applied thereto, and to establishments involved in related research work. It also provides for the security clearance to be applied to persons who shall be authorised to obtain such information and classified material. A Royal Order of 18 October 1974 amends this Order in respect of the authorities responsible for its implementation. (NEA)
[fr]Cette Loi regit la surete de l'Etat dans le domaine de l'energie nucleaire et dispose que le Roi peut determiner les mesures de surete qui doivent etre respectees en ce qui concerne la recherche et les matieres nucleaires, les methodes de production utilisees par des etablissements et des personnes morales ou physiques qui possedent des informations, des documents ou des matieres obtenus soit directement du Gouvernement, soit avec son autorisation. Cette Loi a ete suivie par un Arrete royal du 14 mars 1956 qui complete ses dispositions en fixant des conditions precises pour la classification des informations et des matieres, les mesures de securite applicables a ces informations et documents ainsi qu'aux etablissements affectes a des recherches y relatives. La Loi prevoit egalementnt la procedure requise pour autoriser des personnes a obtenir de telles informations et des matieres classifiees. Un Arrete royal du 18 octobre 1974 modifie cet Arrete en ce qui concerne les autorites responsables pour son execution
[en] We present a unified formalism for threshold quantum secret sharing using graph states of systems with prime dimension. We construct protocols for three varieties of secret sharing: with classical and quantum secrets shared between parties over both classical and quantum channels.
[en] This Decree lays down that rules may be made to secure the secrecy of a number of nuclear matters. An obligation to observe secrecy may be imposed upon persons engaged in the nuclear activities listed in the Decree if the interest of the State so requires. The competent Minister for the activity concerned is empowered to impose this obligation. (NEA)
[fr]Le present Decret stipule que des reglements peuvent etre etablis en vue d'assurer le secret concernant un certain nombre de questions nucleaires. Les personnes qui exercent les activites nucleaires enumerees dans le Decret peuvent se voir imposer le secret si les interets de l'Etat l'exigent. Le Ministre competent pour l'activite concernee est habilite a imposer l'obligation au secret
[en] The reactor systems which were developed by the nuclear pioneering nations behind curtains of secrecy during the decade and a half after the discovery of fission, are discussed in the light of the international situation of the time. (U.K.)
[en] Industrial devices are more and more connected which has generated numerous weaknesses and flaws in networks. Most attacks concern basic things. The French law about military programming defines vital infrastructures whose operators must comply with a minimal cyber security standard. These vital infrastructures include water treatment plants, nuclear power plants or hospitals. In last december the black-ware BlackEnergy enabled hackers to access the management systems of several power plants in Ukraine causing a huge power outage. Technical solutions exist but solving this issue is above all a question of method: you must study your network, identifying the fluxes of information and then to set adequate solutions at the right places. By positioning components able to analyse fluxes you can detect abnormal fluxes and bar the access. The right settings of software like firewalls are an important thing to get a high standard of security. For external communication efficient encoding solutions exist that ensure a high level of secrecy and can identify the contact person. (A.C.)