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International audience ; We propose and discuss foundations for programmable overlay networks and overlay computing systems. Such overlays are built over a large number of distributed computational individuals, virtually organized in colonies, and ruled by a leader (broker) who is elected or imposed by system administrators. Every individual asks the broker to log in the colony by declaring the resources that can be offered (with variable guarantees). Once logged in, an individual can ask the broker for other resources. Colonies can recursively be considered as evolved individuals who can log in an outermost colony governed by another (super)-broker. Communications and routing intra-colonies goes through a broker-2-broker PKI-based negotiation. Every broker routes intra- and inter- service requests by filtering its resource routing table, and then by forwarding the request first inside its colony, and second outside, via the proper super-broker (thus applying an endogenous-first-estrogen-last strategy). Theoretically, queries are formulæ in first-order logic equipped with a small program used to orchestrate and synchronize atomic formulæ. When the client individual receives notification of all (or part of) the requested resources, then the real resource exchange is performed di- rectly by the server(s) individuals, without any further mediation of the broker, in a pure peer-to-peer fashion. The proposed overlay promotes an intermittent participation in the colony, since peers can appear, disappear, and organize themselves dynamically. This implies that the routing process may lead to failures, because some individuals have quit, or are temporarily unavailable, or they were logged out manu militari by the broker due to their poor performance or greediness. We design, validate through simulation, and implement these foundations in a programmable overlay computer system, called Arigatoni.

International audience ; We propose and discuss foundations for programmable overlay networks and overlay computing systems. Such overlays are built over a large number of distributed computational individuals, virtually organized in colonies, and ruled by a leader (broker) who is elected or imposed by system administrators. Every individual asks the broker to log in the colony by declaring the resources that can be offered (with variable guarantees). Once logged in, an individual can ask the broker for other resources. Colonies can recursively be considered as evolved individuals who can log in an outermost colony governed by another (super)-broker. Communications and routing intra-colonies goes through a broker-2-broker PKI-based negotiation. Every broker routes intra- and inter- service requests by filtering its resource routing table, and then by forwarding the request first inside its colony, and second outside, via the proper super-broker (thus applying an endogenous-first-estrogen-last strategy). Theoretically, queries are formulæ in first-order logic equipped with a small program used to orchestrate and synchronize atomic formulæ. When the client individual receives notification of all (or part of) the requested resources, then the real resource exchange is performed di- rectly by the server(s) individuals, without any further mediation of the broker, in a pure peer-to-peer fashion. The proposed overlay promotes an intermittent participation in the colony, since peers can appear, disappear, and organize themselves dynamically. This implies that the routing process may lead to failures, because some individuals have quit, or are temporarily unavailable, or they were logged out manu militari by the broker due to their poor performance or greediness. We design, validate through simulation, and implement these foundations in a programmable overlay computer system, called Arigatoni.

International audience ; We propose and discuss foundations for programmable overlay networks and overlay computing systems. Such overlays are built over a large number of distributed computational individuals, virtually organized in colonies, and ruled by a leader (broker) who is elected or imposed by system administrators. Every individual asks the broker to log in the colony by declaring the resources that can be offered (with variable guarantees). Once logged in, an individual can ask the broker for other resources. Colonies can recursively be considered as evolved individuals who can log in an outermost colony governed by another (super)-broker. Communications and routing intra-colonies goes through a broker-2-broker PKI-based negotiation. Every broker routes intra- and inter- service requests by filtering its resource routing table, and then by forwarding the request first inside its colony, and second outside, via the proper super-broker (thus applying an endogenous-first-estrogen-last strategy). Theoretically, queries are formulæ in first-order logic equipped with a small program used to orchestrate and synchronize atomic formulæ. When the client individual receives notification of all (or part of) the requested resources, then the real resource exchange is performed di- rectly by the server(s) individuals, without any further mediation of the broker, in a pure peer-to-peer fashion. The proposed overlay promotes an intermittent participation in the colony, since peers can appear, disappear, and organize themselves dynamically. This implies that the routing process may lead to failures, because some individuals have quit, or are temporarily unavailable, or they were logged out manu militari by the broker due to their poor performance or greediness. We design, validate through simulation, and implement these foundations in a programmable overlay computer system, called Arigatoni.

Security-sensitive components, such as single sign-on APIs, need to be safely deployed on untrusted webpages. We present several new attacks on security components used in popular web applications that demonstrate how failing to isolate such components leaves them vulnerable to attacks both from the hosting website and other components loaded on the same page. These attacks are not prevented by browser security mechanisms alone, because they are caused by code interacting within the same origin. To mitigate these attacks, we propose to combine fine-grained component isolation at the JavaScript level with cryptographic mechanisms. We present Defensive JavaScript (DJS), a subset of the language that guarantees the behavioral integrity of trusted scripts loaded in an untrusted page. We give a sound type system, type inference tool and build defensive libraries for cryptography and data encodings. We show the effectiveness of our solution by implementing several isolation patterns that fix some of our original attacks. We use a translation of a fragment of DJS to to applied pi-calculus to verify concrete security policies of critical components against various classes of web attackers. ; Certaines librairies critiques pour la sécurité, par exemple pour l'authentification unique (single sign-on), nécéssitent d'être chargées dans des sites tiers non sûrs. Nous montrons comment le manque d'isolation entre ces librairies et leur page hôte les rendent vulnérables aux scripts tiers qui partagent le même environnement, y compris pour des services très largements utilisés. Les mécanismes de sécurité des navigateurs sont impuissants face à ces attaques car elles interviennent en dessous de la granularité des politiques de sécurité, fixée par origine (protocole, nom de domaine et numéro de port). Afin de mitiger ces attaques, nous proposons de combiner une isolation fine de ces librairies au niveau du langage avec des protections cryptographiques. À cette fin, nous introduisons DJS, un fragment de JavaScript qui protège ...

International audience ; While online services emerge in all areas of life, the voting procedure in many democracies remains paper-based as the security of current online voting technology is highly disputed. We address the issue of trustworthy online voting protocols and recall therefore their security concepts with its trust assumptions. Inspired by the Bitcoin protocol, the prospects of distributed online voting protocols are analysed. No trusted authority is assumed to ensure ballot secrecy. Further, the integrity of the voting is enforced by all voters themselves and without a weakest link, the protocol becomes more robust. We introduce a taxonomy of notions of distribution in online voting protocols that we apply on selected online voting protocols. Accordingly, blockchain-based protocols seem to be promising for online voting due to their similarity with paper-based protocols.

Network security is becoming increasingly important to personal computer users, businesses, and the military. Security became a major concern with the advent of the internet, and understanding the history of security allows a better understanding of the emergence of security technology. Many security threats can occur due to the structure of the internet. If the internet's architecture is changed, it can reduce the number of possible attacks that can be sent across the network. Knowing the attack methods enables us to respond with adequate security. Many businesses use firewalls and encryption mechanisms to protect themselves from the internet. To stay connected to the internet, businesses create an "intranet.