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.

System for consulting and/or updating dns servers and/or ldap directories

Abstract: A database in a system for consulting and/or updating one or more resource records, is stored by a domain name server, (DNS server), or a directory server, (the LDAP server), indirectly accessed from a DNS server. A communication arrangement enables the system to receive from a telecommunication terminal a request for consultation and/or modification of the record or a programming of such a request. A controller determines, from the consultation and/or modification request transmitted to the system or previously programmed in the system, a domain name and an operation to be performed on the record. A protocol manager searches, from the domain name, the IP address of the server storing the database and, according to the operation, transmits to the server a request to read or update the record.

Optical packet switching system

Abstract: An optical signal switch identifies the routing of each optical packet, directs each packet arriving at any input to the output corresponding to the routing, and includes delay lines through which the optical signals pass selectively. The switch has three stages: a first stage directing each optical packet received at an input to a chosen delay line, a second stage coupled to the output of the delay lines to direct the optical packets selectively to the output corresponding to the determined routing, and an output third stage.

Time series modeling for IDS alert management

Abstract: Intrusion detection systems create large amounts of alerts. Significant part of these alerts can be seen as background noise of an operational information system, and its quantity typically overwhelms the user. In this paper we have three points to make. First, we present our findings regarding the causes of this noise. Second, we provide some reasoning why one would like to keep an eye on the noise despite the large number of alerts. Finally, one approach for monitoring the noise with reasonable user load is proposed. The approach is based on modeling regularities in alert flows with classical time series methods. We present experimentations and results obtained using real world data.

A set of algorithms linking NLMS and block RLS algorithms

Abstract: This paper describes a set of block processing algorithms which contains as extremal cases the normalized least mean squares (NLMS) and the block recursive least squares (BRLS) algorithms. All these algorithms use small block lengths, thus allowing easy implementation and small input-output delay. It is shown that these algorithms require a lower number of arithmetic operations than the classical least mean squares (LMS) algorithm, while converging much faster. A precise evaluation of the arithmetic complexity is provided, and the adaptive behavior of the algorithm is analyzed. Simulations illustrate that the tracking characteristics of the new algorithm are also improved compared to those of the NLMS algorithm. The conclusions of the theoretical analysis are checked by simulations, illustrating that, even in the case where noise is added to the reference signal, the proposed algorithm allows altogether a faster convergence and a lower residual error than the NLMS algorithm. Finally, a sample-by-sample version of this algorithm is outlined, which is the link between the NLMS and recursive least squares (RLS) algorithms. >

Determinants of mobile phone output power in a multinational study: Implications for exposure assessment

Abstract: Objectives: The output power of a mobile phone is directly related to its radiofrequency (RF) electromagnetic field strength, and may theoretically vary substantially in different networks and phone use circumstances due to power control technologies. To improve indices of RF exposure for epidemiological studies, we assessed determinants of mobile phone output power in a multinational study. Methods: More than 500 volunteers in 12 countries used Global System for Mobile communications software-modified phones (GSM SMPs) for approximately 1 month each. The SMPs recorded date, time, and duration of each call, and the frequency band and output power at fixed sampling intervals throughout each call. Questionnaires provided information on the typical circumstances of an individual's phone use. Linear regression models were used to analyse the influence of possible explanatory variables on the average output power and the percentage call time at maximum power for each call. Results: Measurements of over 60 000 phone calls showed that the average output power was approximately 50% of the maximum, and that output power varied by a factor of up to 2 to 3 between study centres and network operators. Maximum power was used during a considerable proportion of call time (39% on average). Output power decreased with increasing call duration, but showed little variation in relation to reported frequency of use while in a moving vehicle or inside buildings. Higher output powers for rural compared with urban use of the SMP were observed principally in Sweden where the study covered very sparsely populated areas. Conclusions: Average power levels are substantially higher than the minimum levels theoretically achievable in GSM networks. Exposure indices could be improved by accounting for average power levels of different telecommunications systems. There appears to be little value in gathering information on circumstances of phone use other than use in very sparsely populated regions.