Orange S.A.

About: Orange S.A. is a company organization based out in Paris, France. It is known for research contribution in the topics: Terminal (electronics) & Signal. The organization has 6735 authors who have published 9190 publications receiving 156440 citations. The organization is also known as: Orange SA & France Télécom.

Resistance of SNOW 2.0 against algebraic attacks

Abstract: SNOW 2.0, a software oriented stream cipher proposed by T. Johansson and P. Ekdahl in 2002 as an enhanced version of the NESSIE finalist SNOW 1.0, is usually considered as one of the strongest stream ciphers designed so far. This paper investigates the resistance of SNOW 2.0 against algebraic attacks. This is motivated by the fact that the main source of non-linearity in SNOW 2.0 comes from a permutation build upon the AES S-box, which inputs and outputs are well known to be related by numerous quadratic equations. We show that a slightly modified version of SNOW 2.0 is susceptible to an algebraic attack with time complexity about 250, and which requires no more than 1000 words of output. We then explore various ways to extend this attack to the actual stream cipher.

A design framework for asynchronous/synchronous circuits based on CHP to HDL translation

Abstract: An open design framework, which allows mixing asynchronous and synchronous circuit styles, is presented. It is based on the development of a tool called "CHP/sub 2/VHDL" which automatically translates CSP-like specifications (Communicating Sequential Processes) into VHDL programs. This work follows two main motivations: (i) to provide the asynchronous circuit designers with a powerful execution/simulation framework mixing high-level CSP descriptions, HDL programs and gate level descriptions, (ii) to give to synchronous designers familiar with existing HDL-based top-down design flows, the opportunity to include clockless circuits in their designs. An extension of the CHP language proposed by A.J. Martin (1990) is presented and its simulation-oriented features are discussed. The "CHP/sub 2/VHDL" translator and its software environment are then described. Finally, a significant design experiment is considered to illustrate the efficiency of the design framework.

Method of associating forwarding references with data packets by means of a TRIE memory, and packet processing device applying such method

Abstract: Different portions of a header of each packet containing protocol data are analyzed in succession from different gate registers of the TRIE memory. As a packet arrives, its header is stored in a buffer memory and a first portion of the stored header is analyzed. Each analysis of a portion of header produces either the forwarding reference associated with the packet or an intermediate reference containing a first code, making it possible to locate at an arbitrary location of the buffer memory a next portion to be analyzed, and a second code, making it possible to locate at an arbitrary location of the TRIE memory a gate register from which this next portion is to be analyzed. Having analyzed the first portion of a stored header, the subsequent portions thereof are analyzed in accordance with the first and second codes contained in the intermediate references produced in succession until the forwarding reference is produced.

Semantic Web Service Composition through a Matchmaking of Domain

Abstract: The automated composition of Web services is one of the most promising ideas and at the same time one of the most challenging research area for the taking off of service-oriented applications. It is widely recognised that one of the key elements for the automated composition of Web services is semantics, i.e. unambiguous descriptions of Web services capabilities and processes. However Web services described at capability level need a formal context to perform the automated composition of Web services. In this paper a TLB architecture (three levels based architecture) is presented to perform Web service composition. Moreover we introduce the composition process as a matchmaking of domains and solve the latter problem according to a formal model, i.e. the xCLM (eXtended causal link matrix) and a knowledge base of the domain

Learning and integration of parameterized components through testing

Abstract: We investigate the use of parameterized state machine models to drive integration testing, in the case where the models of components are not available beforehand. Therefore, observations from tests are used to learn partial models of components, from which further tests can be derived for integration. We have extended previous algorithms to the case of finite state models with predicates on input parameters and observable non-determinism. We also propose a new strategy where integration tests can be derived from the data collected during the learning process. Our work typically addresses the problem of assembling telecommunication services from black box COTS.