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.

Cryptanalysis of rainbow

Abstract: Rainbow is a fast asymmetric multivariate signature algorithm proposed by J. Ding and D. Schmidt in [5]. This paper presents a cryptanalysis of Rainbow which enables an attacker provided with the public key to recover an equivalent representation of the secret key, thus allowing her to efficiently forge a signature of any message. For the set of parameter values recommended by the authors of Rainbow in order to achieve a security level strictly higher than 280, the complexity of our attack is less than 271 operations. This is 240 times less than the complexity of the best known attack used by the authors to dimension their system.

Process for obtaining a layer of single-crystal germanium or silicon on a substrate of single-crystal silicon or germanium, respectively

Abstract: The process consists in depositing, by chemical vapor deposition using a mixture of silicon and germanium precursor gases, a single-crystal layer of silicon or germanium on a germanium or silicon substrate by decreasing or increasing the temperature in the range 800-450° C. and at the same time by increasing the Si/Ge or Ge/Si weight ratio from 0 to 100% in the precursor gas mixture, respectively.

System for management of the usage of data consultations in a telecommunication network

Abstract: A system for management of the usage of consultations in a telecommunication network, in which one consultation is carried out by communication between a remote server center, and a local subscriber terminal, via a telecommunication link of switched type. A usage management module is provided, which is external to the link and makes it possible, through interactive communication between the local subscriber terminal and the management module, as well as between the management module and the remote server center, to set up, monitor and acknowledge the usage between the remote server center and a subscriber terminal.

Optical wireless communications for broadband access in home area networks

Abstract: As a part of the EU-FP7 R&D programme, the OMEGA project (hOME Gigabit Access) aims at bridging the gap between mobile broadband terminals and the wired backbone network in homes. To provide Gb/s connectivity a combination of various technologies is considered. Beside radio frequencies, the wireless links will use infrared and visible light. Combined with power-line communications this enables a home area network (HAN) that meets the vision of broadband home networking dasiawithout new wirespsila. A technology-independent MAC layer is foreseen to control such network and to provide services as well as connectivity to any device the user wishes to connect. Moreover, this MAC layer should allow the service to follow the user from device to device in any room of a building /apartment. The contribution presents ideas and approaches for broadband optical wireless (OW) communications using infrared Gb/s hotspots and 100 Mb/s information broadcasting by means of interior lighting based on white-light LEDs. Important issues concerning the physical layer are discussed.