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.

A traceable block cipher

Abstract: In this paper we propose a new symmetric block cipher with the following paradoxical traceability properties: it is computationally easy to derive many equivalent secret keys providing distinct descriptions of the same instance of the block cipher. But it is computationally difficult, given one or even up to k equivalent keys, to recover the so called meta-key from which they were derived, or to find any additional equivalent key, or more generally to forge any new untraceable description of the same instance of the block cipher. Therefore, if each legitimate user of a digital content distribution system based on encrypted information broadcast (e.g. scrambled pay TV, distribution over the Internet of multimedia content, etc.) is provided with one of the equivalent keys, he can use this personal key to decrypt the content. But it is conjectured infeasible for coalitions of up to k traitors to mix their legitimate personal keys into untraceable keys they might redistribute anonymously to pirate decoders. Thus, the proposed block cipher inherently provides an efficient traitor tracing scheme [4]. The new algorithm can be described as an iterative block cipher belonging to the class of multivariate schemes. It has advantages in terms of performance over existing traitor tracing schemes and furthermore, it allows to restrict overheads to one single block (i.e. typically 80 to 160 bits) per encrypted content payload. Its strength relies upon the difficulty of the “Isomorphism of Polynomials” problem [17], which has been extensively investigated over the past years. An initial security analysis is supplied.

Apparatuses and method for controlling access to an IP multimedia system from an application server

Abstract: A security node (SN) controls access to an internet protocol multi-media system (IMS) (1) from an application server (12) outside the system. The multi-media system includes a session protocol server S-CSCF (4) and a subscriber database HSS (2). The security node comprises a database access control node operable to control access to the subscriber database HSS from the application server, a session message control node operable to control communication of the messages to the session protocol server from the application server, and a control information database for storing control data. The control data specifies conditions for accessing the subscriber database HSS and for communicating with the session protocol server S-CSCF. The database access control node is operable to control access to the subscriber database in accordance with the control data, and the session message control node is operable to control communication of messages to the session protocol server in accordance with the control data. Embodiments of the present invention can provide a facility for an application server operating externally to an internet protocol multi-media system IMS network to have controlled access to resources within the IMS network. For example, the access may be controlled in accordance with a policy agreed between an operator of the IMS network and an operator of the application server.

MPEG-7 Systems: overview

Abstract: This paper gives an overview of Part 1 of ISO/IEC 15939 (MPEG-7 Systems). It first presents the objectives of the MPEG-7 Systems activity. In the MPEG-1 and MPEG-2 standards, "Systems" referred only to overall architecture, multiplexing, and synchronization. In MPEG-4, in addition to these issues, the Systems part encompasses interactive scene description, content description, and programmability, MPEG-7 brings new challenges to the Systems expertise, such as languages for description representation, binary representation of descriptions, and delivery of descriptions either separate or jointly with the audio-visual content. The paper then presents the description of the MPEG-7 Systems specification, starting from the general architecture up to the description of the individual MPEG-7 Systems tools. Finally, a conclusion describes the status of the standardization effort, as well as future extensions of the specification.

Honeypots: practical means to validate malicious fault assumptions

Abstract: We report on an experiment run with several honeypots for 4 months. The motivation of this work resides in our wish to use data collected by honeypots to validate fault assumptions required when designing intrusion-tolerant systems. This work in progress establishes the foundations for a feasibility study into that direction. After a review of the state of the art with respect to honeypots, we present our test bed, discuss results obtained and lessons learned. Avenues for future work are also proposed.