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Book review ; International audience ; Distributed System V (FMOODS) is not a book. It is a luxurious conference proceeding, edited in 2002 under the "shield" of IFIP TC6-WG6.1. FMOODS conference bring researchers from various fields: formal methods (model checking, abstract interpretation, type theory, Hoare-logic, etc.), distributed systems (CSP, pi-calculus, ambients, petri nets, actors, agents, ORB's, etc.), and "all around" object-based theory and practice. Applications in the above fields are various, crucial and pragmatic. Just to mention a few of these: hardware design, security and communication protocols, distributed-embedded-concurrent-collaborative systems, Java software verification, middleware, interoperability, computer-aided collaborative work, air traffic control, telephony features, etc. We think that the community of researchers involved in developing those applications is now mature to use formal methods (and proof assistants) to design/develops/certify "safe software" in the above "hot fields". The major cost in the design phase (it is well understood that a fairly concrete mathematical model costs more in terms of human resources than a UML chart) will benefit from a major "solidity" of the specification of the related software; in latest experiments using certain proof assistants, proofs of the soundness of the specifications can be turned directly into executable code. We are of course far from a "democratization" of such techniques (which can actually be used only by experts) but their recent use in the setting of formal certification of critical applications such as smart-card, embedded software, compilers, protocols for cryptography, Java language, etc., shows that in the near future their use might be as widespread as the use of C++ libraries, or design patterns, or object-orientation. A few drawbacks: the rate of submitted/accepted papers is not known, and only one of the three invited presentations have produced a regular paper (the others ones only gives abstracts). Moreover, ...

Book review ; International audience ; Distributed System V (FMOODS) is not a book. It is a luxurious conference proceeding, edited in 2002 under the "shield" of IFIP TC6-WG6.1. FMOODS conference bring researchers from various fields: formal methods (model checking, abstract interpretation, type theory, Hoare-logic, etc.), distributed systems (CSP, pi-calculus, ambients, petri nets, actors, agents, ORB's, etc.), and "all around" object-based theory and practice. Applications in the above fields are various, crucial and pragmatic. Just to mention a few of these: hardware design, security and communication protocols, distributed-embedded-concurrent-collaborative systems, Java software verification, middleware, interoperability, computer-aided collaborative work, air traffic control, telephony features, etc. We think that the community of researchers involved in developing those applications is now mature to use formal methods (and proof assistants) to design/develops/certify "safe software" in the above "hot fields". The major cost in the design phase (it is well understood that a fairly concrete mathematical model costs more in terms of human resources than a UML chart) will benefit from a major "solidity" of the specification of the related software; in latest experiments using certain proof assistants, proofs of the soundness of the specifications can be turned directly into executable code. We are of course far from a "democratization" of such techniques (which can actually be used only by experts) but their recent use in the setting of formal certification of critical applications such as smart-card, embedded software, compilers, protocols for cryptography, Java language, etc., shows that in the near future their use might be as widespread as the use of C++ libraries, or design patterns, or object-orientation. A few drawbacks: the rate of submitted/accepted papers is not known, and only one of the three invited presentations have produced a regular paper (the others ones only gives abstracts). Moreover, ...

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.