Abstract: This report shows how to apply Howe’s method,for the proof of congruence of early bisimilarities in higher-order process calculi. This involves the introduction of a new kind of transition system and a new kind of bisimilarity, collectively called complementary,semantics. We show that complementary,semantics is equivalent to contextual semantics, originally introduced by Sangiorgi, that relies on classical tran- sition systems for higher-order calculi and context bisimilarity. Key-words: Process calculus, bisimilarity, bisimulation, early bisimilarity, Howe’s

In this report, we present the first results of a study on the mo deling of data-intensive parallel applications following the synchronous approach . More precisely, we consider the GASPARD extension of ARRAY-OL, which is dedicated to System-on-Chip codesign. We define an associated synchronous dataflow equational model tha t enables to address several design correctness issues (...

Abstract: This memorandum,outlines the goals for and constraints on an IP address and prex,autoconguration,mechanism for mobile ad hoc networks. Key-words: mobile network, ad hoc network, network architecture, address conguration,

In this paper we address the stabilizing leader election problem in the popu- lation protocols model augmented with oracles. Population protocols is a recent model of computation that captures the interactions of biological systems. In this model emergent global behavior is observed while anonymous nite-state agents(nodes) perform local peer interactions. Uniform self-stabilizing leader election is impossible in such systems without additional assumptions. Therefore, the classical model has been augmented with the even- tual leader detector, ?, that eventually detects the presence or absence of a leader. In the augmented model several solutions for leader election in rings and complete networks have been proposed. In this work we extend the study to trees and arbitrary topologies. We propose deterministic and probabilistic solutions. All the proposed algorithms are memory optimal | they need only one memory bit per agent. Additionally, we prove the necessity of the eventual leader detector even in environments helped by randomization.