Maestrois an Inriaproject-team whose all members are located in Sophia Antipolis except E. Altman who is located at Laboratoire Informatique d'Avignon (LIA) in Avignon, and A.-E. Baert and A. Jean-Marie who are both located at Lirmmin Montpellier. Maestrois concerned with the modeling, performance evaluation, optimization and control of discrete-event dynamical systems ( Deds), with a particular emphasis on networks and their applications. The scientific contributions are both theoretical, with the development of new modeling formalisms, and applied with the development of software tools for the performance evaluation of Deds.

Research activities in 2007 have focused on the following issues:

performance evaluation of wireless, mobile, ad hoc and sensor networks, within the Istproject Bionets, a grant from France Telecom R&Dand the support of Cefipra(French-Indian collaboration);

analysis of the WIMAX protocol within the Anrgrant Winem;

design and evaluation of a software for the tracking of multimedia content published on the Web within the Anrgrant Spi3-Pro;

analysis of sized-based scheduling schemes, and performance evaluation of peer-to-peer protocols using stochastic models with the support of France Telecom R&Dand Network of Excellence Euro-NFi;

singularly perturbed Markov chains and time-average optimal control in the framework of the French-Australian grant Linkage International.

The main mathematical tools and formalisms used in Maestroinclude:

theory of stochastic processes: Markov process, point process, Palm measure, large deviations;

theory of dynamical discrete-event systems: queues, fluid approximation, network calculus;

theory of control and scheduling: dynamic programming, Markov decision process, game theory, deterministic and stochastic scheduling, pathwise comparison;

theory of singular perturbations;

random matrix theory.

Our main application area is networking and in particular, modeling, performance evaluation, optimization and control of protocols and network architectures. It includes:

Internet infrastructure: Tcp, high speed congestion control, voice over Ip, service differentiation, quality of service;

Internet applications: multicast, content distribution systems, peer-to-peer systems, overlay networks, multimedia traffic;

Wireless (cellular, ad hoc, sensor) networks: Wlan, Wimax, Umts, delay tolerant networks, power control, medium access control, transmission rate control, redundancy in source coding, mobility models, coverage, routing.

In 2007, K. Avrachenkov, D. Nemirovsky and E. Smirnova have continued to develop the software “Web Graph Analyzer” for the investigation of Web Graph properties. In particular, during 2007 we have added a visualization module to the software.

In collaboration with Canonwe have developed a Web Crawler for crawling images from targeted Web Sites. This Crawler is used by Canonin a software which helps independent photographers to detect uncopyright use of their material. Distinctive features of our Crawler are: efficient sub-optimal refresh policy, extracting images from Flash based Web sites, managing several http connections inside one Java thread.

This work was supported by Anrgrant Spi3-Pro(see Section ).

This work was supported by France Telecom R&Dgrant on "Modĺisation et Gestion du Traffic dans le Réseau Internet" (see Section ).

Power save/sleep mode operation is the key point for energy-efficient usage of mobile devices driven by limited battery lifetime. In
, S. Alouf, E. Altman and A. Azad establish a general approach for analyzing queueing models
with repeated inhomogeneous vacations and apply it for the study of the power save mode defined in the
Ieee802.16e
Wimaxstandard. They derive the sojourn time in a
M/
G/1queue with repeated vacations and the energy consumption when the power saving is activated as function of the protocol parameter. A constrained optimization
problem is formulated and solved for the optimal values of the protocol parameters.

This research is carried out within ANR grant Winem(see Section ).

Building on E. Altman, in collaboration with D. Miorandi ( Create-Net, Trento, Italy), A. Kumar and M. Goyal ( IISc, Bangalore, INDIA), has developed an important generalization of the pioneering paper by G. Bianchi (over 1530 citations) on the performance evaluation of the IEEE 802.11 protocol. Their work, which considerably simplifies the solution method of G. Bianchi, and at the same time relaxes the memoryless assumption on the back-off durations, has now appeared in .

The research in this topic has been partially funded by the Ist Fetgrant Bionets(see Section ).

S. Alouf, A. Fialho and G. Neglia, together with I. Carreras and D. Miorandi ( Create-Net, Trento, Italy), have developed a framework to let forwarding schemes for Delay Tolerant Networks evolve in order to adapt to changing and a priori unknown environments. The framework is inspired by genetic algorithms: at each node a genotype describes the forwarding scheme used, a selection process fosters the diffusion of the fittest genotypes in the system and new genotypes are created by combining existing ones or by applying random changes. A case study implementation is presented in and in . Simulation results indicate that the proposed case-study implementation is able to track changes in the system conditions (e.g., number of nodes in the considered scenario), and achieves similar if not better performance than solutions statically optimized for a given operating point. A systematic analysis of the following issues is under study: parameters setting for the genetic operators used to generate new genotypes, evaluation of the convergence of the evolutionary mechanism, fitness definition. Preliminary results are reported in .

The possibility to employ reaction-diffusion models to build spatial patterns in sensor networks has already been advocated. However it has not been investigated how do these biologically-inspired solutions perform in comparison to more traditional ones, taking into account specificities of sensor networks like severe energy constraints. In , G. Neglia and G. Reina have presented some preliminary results on the comparison between a biologically inspired coordination mechanism based on activator-inhibitor interaction and a simple mechanism, where nodes do not communicate but activate their sensing circuitry according to some probability. It appears that the activator-inhibitor mechanism is able to spare energy for sensing purpose, activating a smaller number of sensors. At the same time, a high number of messages is needed in order to establish the pattern starting from a clean slate status.

This work received the
**Best Paper Award**of the
**Bionetics 2007 conference**.

Evolutionary games are used for large populations; the corresponding solution concept (ESS - Evolutionary Stable Strategies) is defined as a distribution of strategies among the populations such that no mutation can intrude the existing populations; in other words, it is robust against a deviation of not only a single player (as is the case with the Nash equilibrium in the standard non-cooperative game theory) but even against deviations of a whole fraction of the population. Evolutionary games also focus on the evolution of strategies of players and on conditions for their convergence or non-convergence to an equilibrium.

In
,
,
E. Altman, in collaboration with R. El-Azouzi, T. Hamidou and Y. Hayel (Univ. of Avignon, France), has
developed the theoretical foundations of the theory of evolutionary games, studying stability conditions. They have extended the mathematical model to a new class of
**stochastic evolutionary games**. They have applied this formalism to study various networking problems including (i) competitive routing
(in collaboration with H. Kameda – Univ. of Tsukuba, Japan ), (ii) the association problem in wireless access
(in collaboration with S. Shattokkai (Univ. of Illinois at Urbana-Champaign, USA) and A. Kumar (
IISc, Bangalore, India)) and (iii) the evolution of TCP protocols in the Internet
.

The research on “Mobile ad hoc networks” has been partially supported by by the Ist Fetgrant Bionets(see Section ).

In collaboration with P. Bernhard (UNSA) and M. Debbah ( Institut Eurecom), E. Altman and A. Silva have investigated massively dense ad hoc networks. They have studied their continuum limits as the node density increases and as the graph providing the available routes becomes a continuous area with location and congestion dependent costs. Using techniques from vector calculus they have derived simple structural results on optimal routing when the cost does not depend on the congestion. They have also studied the congestion-dependent case under various formulations: global optimization, individual optimization and Nash equilibrium among several competing operators , .

Jointly with A. Kumar and V. Ramaiyan ( IIScBangalore, INDIA) and V. Ramaiyan, E. Altman has addressed joint power control and routing in massively dense single cell ad hoc networks. The transmission power determines the range and therefore the number of hops between a source and a destination. The number of hops together with the range determine the energy consumption. In the energy consumption is optimized by identifying the best range and transmission power.

In , P. Nain and E. Altman, jointly with A. Al Hanbali (Univ. of Twente, The Netherland), R. Groenevelt (former MaestroPhD student, now researcher at Accenture, Sophia Antipolis) and A. Kherani ( IIT, New Delhi, INDIA) have focused on the performance of the relay node in a two-hop relay protocol. Explicit and closed-form expressions for the relay throughput and the expected message waiting time at the relay buffer are provided. This work extends to a limited number of copies.

This is a joint work with B. Miller (Moscow Aviation Institute, Russia) and B. Prabhu ( CWI, Amsterdam, The Netherlands).

In collaboration with A. Garnaev (St Petersburg State Univ., Russia), E. Altman and K. Avrachenkov have applied game theory to the well-known water-filling problem , , . Within this setting, the zero sum-game formulation has been used to solve the jamming problem (in which a malicious user tries to minimize the throughput of packets corresponding to a power controlled channel). Other non zero-sum game formulations of this problem have also been proposed and an important contribution was to obtain explicitly the equilibrium strategies along with their structure and corresponding value.

Much work has been devoted to the scheduling of transmission of packets at a base station as a function of the channel state between the station and the mobiles. In E. Altman, in collaboration with V. Sharma and D. Prasad ( IISC, Bangalore, INDIA), uses Markov decision processes to compute an optimal schedule, and then compares its performance to those obtained by other frequently used methods.

In collaboration with J. M. Kelif ( France Telecom R&D), E. Altman focuses in on a particular subclass of scheduling policies: the class of priority rules, where the priority is a function of the distance of a mobile to the base station. This results in a continuous priority set. In this work the authors compute the expected sojourn time under various priority rules and identify some hybrid priority rules that provide good performance.

This is a joint work with J.-M. Kelif ( France Telecom R&D) and I. Koukoutsidis (FORTH-ICS, Greece).

The standard approach to compute the capacity of UMTS cellular networks has been to identify which of the uplink and downlink directions seems to be the bottleneck, and then to compute the capacity in that direction assuming that there is no bandwidth limitation on the opposit direction. If one does not know a-priori which of the direction is the bottleneck then one would compute the uplink capacity ignoring the downlink limitation, compute the downlink capacity ignoring the uplink limitations and then take the minimum. This approach turns out to over estimate the real joint uplink and downlink capacity, that E. Altman computes in in collaboration with T. Chahed (GET/INT, Evry, France) and S. E. Elayoubi ( France Telecom R&D).

The theory of random matrix theory is used for approximating performance measures that depend on eigenvalues of matrices whose entries are random, when the size of the matrix is large. E. Altman and N. Bonneau have used this theory in conjunction with yet another approximation that is valid asymptotically as the number of mobiles grows. In the case of non-cooperative games, one may approximate the Nash equilibrium as the number of mobiles grows by the Wardrop equilibrium, which is often much easier to compute. In collaboration with M. Debbah ( Institut Eurecom) and A. Hjørungnes (UniK, Oslo, Norway), they have combined both approximations in to solve non-cooperative power control problems in CDMA.

In collaboration with A. Suarez, M. Debbah and L. Cottatellucci ( Institut Eurecom), E. Altman has also applied random matrix theory to solve the optimal decoding order under target rate constraints .

Other applications of random matrices to networking problems can be found in the PhD thesis of N. Bonneau .

An important issue in wireless sensor networks is the characterization of the limiting performance, in terms of both connectivity and coverage. In , E. Altman has studied connectivity issues in static sensor networks using a queueing theoretic setting in collaboration with D. Miorandi and G. Alfano ( Create-Net, Trento, Italy). The approach consists in identifying an equivalence between busy periods in infinite server queues and connectivity ranges in sensor networks.

We have then pursued this work in collaboration with S. Yousefi, R. El-Azouzi and M. Fathy. We studied in , the connectivity of vehicular mobile ad hoc networks and have analyzed the performance gains obtained by adding mobile base stations. In we design optimal routing so as to maximize the life time of a connected path between a given source and a destination.

This problem arises when a mobile has the possibility to connect to several access points, possibly of different technologies. E. Altman, in collaboration with J.-M. Kelif ( France Telecom R&D), A. Kumar ( IISc, Bangalore, India) and S. Shakkottai (Univ. of Illinois at Urbana-Champaign, USA), has investigated both the centralized framework in and the decentralized approach in which the mobiles themselves take the association decisions , .

PageRank is one of the principle criteria according to which Google ranks Web pages. PageRank can be interpreted as a frequency of visiting a Web page by a random surfer and thus it reflects the popularity of a Web page. Google computes the PageRank using the power iteration method which requires about one week of intensive computations. In K. Avrachenkov, N. Litvak, D. Nemirovsky, and N. Osipova propose and analyze Monte Carlo type methods for the PageRank computation. The authors have discovered several advantages of the probabilistic Monte Carlo methods over the deterministic power iteration method: Monte Carlo methods provide good estimation of the PageRank for relatively important pages already after one iteration; Monte Carlo methods have natural parallel implementation; and finally, Monte Carlo methods allow continuous update of the PageRank as the structure of the Web changes.

Reputation systems are indispensable for the operation of Internet mediated services, electronic markets, document ranking systems, P2P networks and ad hoc networks. In K. Avrachenkov, D. Nemirovsky, and K. S. Pham survey available distributed approaches to the graph based reputation measures. Graph based reputation measures can be viewed as random walks on directed weighted graphs whose edges represent interactions among peers. In the distributed approaches to graph based reputation measures are classified into three categories. The first category is based on asynchronous methods. The second category is based on the aggregation/decomposition methods. And the third category is based on the personalization methods which use the information available locally.

As part of the VOODDO project A.-E. Baert and A. Jean-Marie have worked (jointly with V. Boudet, LIRMM, CNRS/University of Montpellier 2) on the dimensioning of the contents distribution platform of the startup society Voddnet. The objective of this project is the development of an innovative visualization interface for video contents, based on a safe, reliable and optimized storage and transport infrastructure. The effectiveness of the infrastructure depends on the way data are distributed in the network of information servers, and on the way data sources are selected for a given downloading request. The problem is thus to develop placement and scheduling algorithms which are adapted one to the other.

A.-E. Baert and A. Jean-Marie jointly with V. Boudet (LIRMM, CNRS/University of Montpellier 2, France) have worked on the problem of data replication and distribution in a particular infrastructure for distributed Video on Demand (VOD). The problem was to minimize the average download time of a document under various assumptions. This particular quality of service metric is not commonly encountered in the literature.

The authors examine the data replication problem in this particular Grid Delivery Network (GDN). In this system, the data are divided into fixed size blocks which must be replicated on hosts to decrease the total download time. The authors have proposed a probabilistic model to optimize the average download time of requests based on the hosts availability and the document size distribution. The objective function induced by this model is a discrete non-linear problem. They showed that this problem can be solved in real values by Lagrangian optimization. In addition, in a particular case, this problem can be reduced to a knapsack problem. Based on these observations, the authors propose approximation algorithms validated by simulations .

Distributed systems using a network of peers has become an alternative solution for storing data. In
, S. Alouf, A. Dandoush and P. Nain propose simple analytical models to evaluate the performance
of peer-to-peer storage systems, assuming that peers lifetime is exponentially distributed. This assumption has been relaxed in
and
to account for hyperexponential lifetimes with
nphases.

E. Altman is co-editing a monograph survey on paradigms from biology, physics and social sciences for wireless networking. A preliminary version has already appeared as a deliverable in .

Another survey on game theory applied to networks, written in collaboration with R. El-Azouzi (Univ. Avignon, France), appeared in .

Pricing could serve as an additional tool in congestion control and in network management as it can regulate demands for different classes of quality of services. In , E. Altman designs a pricing mechanism for purchasing priorities in a differentiated service architecture. The approach is based on computing the equilibrium achieved by the users for a given pricing function, and then on optimizing the network utility over all possible pricing choices.

This is a joint work with R. El-Azouzi (Univ. Avignon, France), R. Márquez (Univ. Los Andes, Mérida, Venezuela), D. Ros and B. Tuffin ( Inriateam Dyonisos).

G. Neglia, in collaboration with G. Lo Presti (
Cern, Switzerland), H. Zhang (Suffolk Univ., USA) and D. Towsley (Univ. of Massachusetts, Amherst, USA) has employed the framework of
network formation games
to characterize the robustness of the Tit-for-Tat strategy implemented in BitTorrent. In particular, they have
characterized in
the set of
*pairwise stable networks*peers and how peers can dynamically reach such configurations. They have also evaluated the loss of efficiency peers experience because of their lack of
coordination and shown that the loss of efficiency is in general unbounded despite the utilization of the Tit-for-Tat strategy.

Fundamental results in stochastic games with constraints and with a distributed information structure have been obtained in by E. Altman, K. Avrachenkov and N. Bonneau, in collaboration with R. El-Azouzi (Univ. Avignon, France), M. Debbah ( Institut Eurecom) and S. D. Menasche (Univ. Massachusetts, Amherst, USA). In these games, each player controls another Markov chain. A player only knows its own state but the state of other players influences also its cost. The authors have established the existence of equilibria among the stationary policies.

An application of this theory to wireless networks
,
has received the
**Best Paper Award**of the
*IEEE Globecom 2007 conference*.

E. Altman has pursued other fundamental research on games with constraints in collaboration with S. Sarkar (Univ of Pennsylvania, USA) and E. Solan (Tel Aviv Univ., Israel). In the authors obtain a solution based on a linear program to compute stationary saddle-point policies in a zero-sum game with constraints stochastic games in which the transition probabilities are controlled by only one player.

In a joint work with A. Bentahar (Post-doctoral fellow of CNRS in the LIRMM laboratory), A. Jean-Marie has extended to the multi-class case the results existing for the single-class case. They have proved the convergence of the stochastic model to the fluid limit, and solved the fluid differential equations with the help of multidimensional renewal theory. The results apply as well to some flavors of “discriminatory” processor sharing.

In collaboration with D. Fiems (Univ. Ghent, Belgium), E. Altman has contributed in to the development of the theory of branching processes with migration in two directions: (i) multi-type continuous state-space and (ii) non-Markov migration process (for both discrete state-space and continuous state-space). They have illustrated the theory by applying it to study the expected waiting times in symmetric polling systems with correlated vacations.

In , N. Osipova has studied the Processor-Sharing queueing model with a hyper-exponential service time distribution and Poisson batch arrival process. In the case of the hyper-exponential service time distribution she has found an analytical expression for the expected conditional response time function and has obtained an alternative proof of its concavity with respect to the service time. N. Osipova has applied the obtained results to the Two Level Processor-Sharing (TLPS) model with the hyper-exponential service time distribution and has found the expected response time for the TLPS model. In contrast with the BPS queue, the expected conditional response time function is not a concave function in the TLPS model.

This work was supported by France Telecom R&Dgrant on "Modélisation et Gestion du Traffic dans le Réseau Internet" (see Section ).

Maestrohas pursued its collaboration with France Telecom R&Dat Issy les Moulineaux within a new two-year research grant (Contrat de Recherche Externalisée, Cre). In 2006 a patent has been filed concerning new policies for scheduling Tcpconnections between dedicated and shared channels in Umts. In 2007 the participants have studied the association problem (which network should a user connect to at any time) within a heterogeneous network environment ( Wlanon one hand, and Umtscellular network on the other hand). Coordinators of this Creare E. Altman for Maestroand J.-M. Kelif for France Telecom R&D.

Since January 2005 Maestrohas been involved in a three-year research grant ( Cre) with France Telecom R&Din Sophia Antipolis, on the theme “Internet Traffic Management and Modeling.” This grant has two major research directions: application of size-based scheduling to Ipnetworks, and analysis of new Tcpversions for high-speed links. In 2007, the participants have derived an accurate bound on the expected sojourn time in a Two Level Processor Sharing queueing system with hyper-exponential service time distribution and infinite number of phases. This allowed us to study the Two Level Processor Sharing system in the case of a heavy-tailed service time distribution. Also, an explicit expression for the expected sojourn time for the Batch Processor Sharing system with the hyper-exponential service time distribution was obtained. This grant was concluded with a final Maestro- France Telecom R&Dseminar with the overview of the achieved results and the discussion on future research.

The aim of this two-year project (2006-2007) is to develop and to evaluate a software for the tracking of multimedia content published on the Web. This tool will be used by free-lance professional photographers to protect their rights against malicious behaviors. The industrial partner is Canonand the work was supervised by professional photographers.

Within this project, the task of Maestrois to develop a software module which will allow an autonomous and an automatic navigation in the Internet. This work builds on the expertise on Web crawlers developed over the years by Maestro.

This project, called Winem, for “ WimaxNetwork Engineering and Multihoming”, started on January 1st 2007 and will last for 3 years. It aims at engineering and evaluating solutions for the issues left open in the Wimaxstandard, such as quality of service and service differentiations. Other issues are related to mobility management, resource allocation, multihoming, pricing, cross-layer optimization and performance tuning. The project partners are: France Telecom R&D, Get( EnstBretagne and Int), Inria( Inriateams Dyonisosand Maestro), Institut Eurecom, Lia(Université d Avignon), and Motorola. S. Alouf is the coordinator for Inria.

On September 21, A. Azad gave a presentation entitled “Power save mode analysis for IEEE 802.16e using
M/
G/1queue with non homogeneous vacations” within a
Winemmeeting organized in Paris.

Members of Maestrowere involved in a research contract with VodDnet, a company funded by Languedoc- Roussillon Incubation. The system under study was a multi-source content distribution infrastructure based on data segmentation and replication. The research convention involved the programming of a simulation software, the design of a mathematical model for the control and performance prediction of the system, and simulation experiments validating the model. A. Jean-Marie coordinated this project.

This industrial collaboration will be followed by a 3-year research grant from the National Research Agency ( Anr Riam Vooddo(2008-2010)).

Members of Maestrowere involved in a research contract with Melaudy, a company funded by Languedoc-Roussillon Incubation. The system under study is a high-fidelity audio streaming system over power lines. The research convention involves the quality of service characterization of different PLC devices at the packet level, and the design of protocols allowing the high-throughput, multi-canal, zero-loss transport of data over this communication medium. A. Jean-Marie was the coordinator of this project.

Maestrois a member of the Network of Excellence (NoE) EuroFGIwhich is a continuation of the EuroNGINetwork of Excellence on “Design and Engineering of the Next Generation Internet, Towards Convergent Multi-Service Networks” (see 2004-2006 Maestroactivity reports).

Within this NoE Maestrofurther participates in one EuroFGISpecific Joint Research Project on Self Organizing Networks.

Maestrois a partner of the IstFetEuropean Integrated Project Bionetson “BIOlogically-inspired autonomic NETworks and Services”. E. Altman is the coordinator of the work package on paradigm collection and foundations.

Bionetsis a project belonging to the IstFetProactive Initiative Program on “Situated and Autonomic Communication”. There are sixteen partners involved and Maestro, together with Inriaproject-team Oasisand colleagues from Institut Eurecom, is one of them. Bionetsis planned for four years and started on January 1st 2006.

Bionetsspecializes on the design of protocols that will allow evolution of services over a self-organizing wireless network that contains a huge amount of cheap sensors, as well as a limited number of intelligent terminals. The project proposes an inter-disciplinary strategy for designing such networks (called bionets) by using methods and tools from biology, physics, economics. Maestro's task is to collect such tools and to adapt them to Bionets.

Maestro, in partnership with Cnrs(J.-B. Lasserre, H. Frankowska), University of Paris Dauphine (J.-P. Aubin), University of Utrecht (A. Gnedin) and University of South Australia (V. Ejov, J. Filar, L. Finlay, V. Gaitsgory, P. Howlett) participates in a three-year (2005-2007) international cooperation grant, Linkage International, of the Australian Research Council on the subject of “Singular Perturbations and Multiscale Models in Optimization and Control”.

Since January 2004 Maestroand Inriaproject-team Oasishave been partners in a four-year collaboration with the University of Los Andes ( Ula), Merida, Venezuela, through a funding of the Ecosprogram. French partners are D. Ros ( Inriaproject-team Armorand EnstBretagne), D. Caromel ( Inriaproject-team Oasis), H. Mounier (University of Paris 11, Orsay), and E. Altman (project coordinator). Our Venezuelan partners are R. Márquez, L. Leon and J. Aguilar from Ula. This year, visits of researchers and students did not include Maestromembers.

Members of Maestroparticipate in the Arc(Cooperative Research Initiative, sponsored by Inria) Ifany“InFormAtioN theorY: New challenges and new interdisciplinary tools” (2006-2007), whose coordinator is E. Altman. Other Inriaproject-teams involved are Trec, Hipercom, Armorand Temics. Other groups participating are EnstBretagne, University of Avignon, France Telecom R&D, Institut Eurecom, Epfl, University of Cyprus and University of Thessaly. The objective of Arc Ifanyis to bring together methods and tools used in traditional information theory, together with new tools (stochastic geometry, game theory, percolation) so as to come up with new notions of capacity of wireless networks.

Website:
http://

Members of Maestroparticipate in the Arc Coinc(2006-2007), headed by B. Gaujal ( Inriaproject-team Mescal), and aimed at developing computational tools and new applications for what is now known as the “network calculus” framework.

Website:
http://

The COLOR (Coopération Locale de Recherche) “Arigatoni on wheels” is a one-year projet focusing on information exchange in Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) systems via an overlay network called Arigatoni, designed by L. Liquori ( Inriaproject-team Mascotte) who coordinated this project. P. Nain participated in this project for Maestro. Other participants are from Politechnico Torino and ETH Zurich.

Website:
http://

U. Ayesta ( Laas, Toulouse, 01/20/07–02/03/07 and 03/18/07–03/26/07); A. Dudin (Belarussian State University, Belarus, 10/09/07-10/19/07); A. Garnaev (St. Petersburg State University, Russia, 05/27/07–06/06/07 and 10/18/07–10/28/07); V. Klimenok (Belarussian State University, Belarus, 10/09/07-10/19/07); G. Koole (Vrije University, Amsterdam, The Netherlands, 04/23/07–05/05/07); G. Miller (MAI, Moscow, Russia, 04/01/07–05/12/07); L. Petrosyan (St. Petersburg State University, Russia, 07/21/07–08/04/07); A. Piunovsky (University of Liverpool, UK, 01/27/07–01/31/07); E. Winands (Eidhoven University of Technology, The Netherlands, 02/07/07–02/24/07); K. Zarifi (Darmstadt University of Technology, Germany, 07/09/07–08/09/07).

T. Başar (University of Illinois at Urbana–Champaign, USA, 03/18/07–03/23/07); S. Sarkar (University of Pennsylvania, USA, 1/10/07–6/15/07); W. Sandholm (University of Wisconsin, USA, 11/18/07–11/30/07].

U. Yechiali (Tel Aviv University, Israel, 03/26/07–03/04/07 and 04/04/07–04/11/07).

V. Ejov (University of South Australia, Adelaïde, Australia, 07/12/07–07/20/07); J. Filar (University of South Australia, Adelaïde, Australia, 06/24/07–07/08/07); V. Gaitsgory (University of South Australia, Adelaïde, Australia, 06/13/07–06/18/07).

visited Inriaproject-team Mescalat INRIA Grenoble - Rhône-Alpes (February 15–16, 2007) gave a seminar within the “Performance Evaluation Seminar in Grenoble”.

visited Tel-Aviv University (Statistics and OR Dept.) and the Technion (EE Dept.), Israel (April 19–29, 2007), and the University of Los Andes (as part of the ECOS program) Merida, Venezuela (July 27 – August 25, 2007).

He was one of four distinguished researchers to be invited by the EE Dept. of the University Autonoma Metropolitana-Iztapalapa of Mexico for the celebration of the 25th anniversary.
During his visit (October 26 – November 5, 2007) he gave an invited talk as part of the event, and another invited talk at the
*Centro de Investigación y Estudios Avanzados del I.P.N*(Cinvestav). He also gave an invited seminar on Constrained Games in the Seminar on Game Theory at HPC Paris (February 5, 2007)
and was an invited speaker in the E-Quality workshop on “Performance Analysis of Mobile and Wireless Communications” at Eurandom, Eindhoven (November 15-16, 2007).

visited Technical University of Tempere on 5–11 March 2007 University of Liverpool on 29 April – 9 May, 2007; St. Petersburg State University on May 17–26, 2007; LAAS CNRS, Toulouse on November 7–12, 2007 .

During his visit in LAAS CNRS K. Avrachenkov gave an invited lecture at MOCOSY seminar series.

visited the Universidad Técnica Federico Santa Maria, Valparaiso, Chile, September 11–30, 2007.

is an Associate Editor of the journals:
*Journal of Economics, Dynamics and Control*(JEDC),
*ACM/Kluwer Wireless Networks*(WINET), and
*Journal of Discrete Event Dynamic Systems*(JDEDS).

is an Associate Editor for
*RAIRO Operations Research*and
*Performance Evaluation*.

is an Associate Editor of
*IEEE/ACM Transactions on Networking*,
*Performance Evaluation*and
*Operations Research Letters*. As of December 17, 2007, P. Nain will become Editor-in-Chief of
*Performance Evaluation*.

IEEE Infocom 2007 (Anchorage, USA)
**(A. Jean-Marie, P. Nain)**

ACM Sigmetrics 2007 (San Diego, CA, USA)
**(P. Nain)**

IEEE International Symposium on Information Theory (ISIT 2007 – Nice, France)
**(E. Altman)**

20th International Teletraffic Congress (ITC-20 – Ottawa, Canada)
**(S. Alouf)**

15th IEEE International Conference on Networks (ICON 2007 – Adelaide, South Australia)
**(K. Avrachenkov)**

2nd International Conference on Performance Evaluation Methodologies and Tools (ValueTools 2007 – Nantes, France)
**(S. Alouf)**

15th IEEE International Symposium on Modeling, Analysis, and Simulation of Computer and Telecommunication Systems (MASCOTS 2007 – Istanbul)
**(K. Avrachenkov)**

7th International Conference on Next Generation Teletraffic and Wired/Wireless Advanced Networking (NEW2AN 2007 – St. Petersburg)
**(K. Avrachenkov)**

IEEE Globecom 2007 Performance Modeling, QoS and Reliability Symposium (Globecom 2007 PMQRS – Washington, DC, USA)
**(S. Alouf)**

1st International Conference on Network Control and Optimization (NET-COOP 2007 – Avignon, France)
**(K. Avrachenkov)**

International Conference on Game Theory and Management (GTM 2007 – St. Petersburg, Russia)
**(E. Altman)**

Workshop on Mathematical performance Modeling and Analysis (MAMA 2007 – San Diego, CA, USA)
**(A. Jean-Marie, P. Nain)**

1st International Workshop on Game theory for Communication networks (Game-Comm 2007 – Nantes, France)
**(E. Altman, K. Avrachenkov)**

1st International Workshop on Network Simulation Tools (NSTools 2007 – Nantes, France)
**(E. Altman)**

ACM Sigmetrics 2007 Student Workshop (San Diego, California, USA)
**(S. Alouf)**

IEEE Wireless Communications and Networking Conference (WCNC 2007 – Hong-Kong, China)
**(E. Altman)**.

was the Publication Chair of the
*Second International Conference on Performance Evaluation Methodologies and Tools*(Valuetools 2007) and of its 4 workshops: GameComm 2007, Inter-Perf 2007, SMCtools 2007 and NSTools
2007 (Nantes, France, October 23–25, 2007). She has co-organized a seminar on Peer-to-Peer networking within the
Intech' Sophia clubthat was held on December 17, 2007.

partipated in the Steering Committee of the following conferences: WiOpt 2007 (
*Workshop on Modeling in Mobile Ad Hoc and Wireless Networks*, Limassol, Cyprus, April 16–20, 2007), Valuetools 2007 (
*2nd International Conference on Performance Evalauation Methodologies and Tools*, Nantes, France, October 23-25, 2007), and NetCoop 2007 (
*International Conference on Network Control and Optimization*, Avignon, France, June 5–7, 2007).

was an invited session chair and organizer at
*EURO XXII Conference 2007*.

participated in the organization of the
*Random Matrix Theory for Wireless Communications*15 hours course, sponsored by
Arc
Ifany(April 13–15, 2007, Limassol, Cyprus) and the meeting for
*IST FET European project BIONETS*partners.

She was a member of the organizing committee of the
*IEEE Information Theory Winter School*(La Colle-sur-Loup, March 12–16, 2007), and a member of the organizing committee of the conference NetCoop 2007 (Avignon, France, June 5–7,
2007).

was a rewiewer of the PhD thesis of Rade Stanojevic (Hamilton Institute, National University of Ireland, Maynooth).

participated as a reviewer in the PhD thesis committees of A. Bušić (U. Versailles St Quentin, Jul. 16, 2007), of H. Charara (INP Toulouse, Nov. 6, 2007), and participated in the thesis committee of T.H. Dao Thi (U. Paris 7, Dec. 3, 2007). He is member of the Best Thesis Award Committee of SPECIF, the French Society for Education and Research in Computer Science.

The following PhD theses were defended in 2007:

on September 24, 2007 (co-advisors: E. Altman and M. Debbah).

is a member of the Doctoral Committee of InriaSophia Antipolis.

is the scientific coordinator of INRIA activities in Montpellier.

is co-head of the Apr(Algorithms and Performance of Networks) project-team of the LirmmLaboratory, a joint research unit of CNRS and the University of Montpellier II.

has been co-chair of the Department of Computer Science of the LirmmLaboratory, Montpellier (80 permanent staff) until June 2007.

is a member of the Recruiting Committee (Commission de Spécialistes) in Computer Science at the University of Montpellier II.

is a member of the Steering Committee of the GDR RO, a national research initiative on Operations Research sponsored by the Cnrs.

has been the Chair of the Project-team Committee of the Research Center of InriaSophia Antipolis - Méditerranée since September 1st, 2007.

is Head of project-team Maestro.

is a member of the management of the Research Center of InriaSophia Antipolis - Méditerranée.

until August 31st, 2007 was the Vice-Chair of the Project-team Committee of the Research Center of InriaSophia Antipolis - Méditerranée.

is a member of the Evaluation Committee of Inria.

until September 1st, 2007, was in charge of the Master program on “Networks and Distributed Systems” at the University of Nice Sophia Antipolis.

is a member of the Steering Committee of the Anr(National Research Agency) research program in Télécommunications.

is a member of the Scientific Committee of the Graduate School of Information and Communication Sciences (école doctorale Stic) of the University of Nice Sophia Antipolis.

is treasurer of Ifip Wg7.3 on “Computer System Modeling”.

E. Altman, K. Avrachenkov and N. Bonneau, with M. Debbah, R. El-Azouzi and D. S. Menasche, have received the
**Best Paper Award**of the
*IEEE Globecom 2007 conference*(November 26-30, 2007, Washington DC, USA)
.

G. Neglia and G. Reina received the
**Best Paper Award**of the
*Bionetics 2007 conference*(December 10–13, 2007, Budapest, Hungary)
.

E. Altman and K. Avrachenkov, with A. Garnaev (St Petersburg State University, Russia), received the
**Second Best Paper Award**of
*EuroFGI NetCoop 2007*(June 5–7, 2007, Avignon, France)
.

P. Nain has been appointed Editor-in-Chief of
*Performance Evaluation*. His term will start on December 17, 2007.

He has been elected for a two-year term (July 1, 2007–June 30, 2009) at the Board of Directors of ACM Sigmetrics.

E. Altman, A Jean-Marie and P. Nain are (elected) members of Ifip Wg7.3 on “Computer System Modeling”.

participated in the course on “Performance Evaluation of Networks” in the Master Program on “Networks and Distributed Systems” at the University of Nice Sophia Antipolis (6H), and in the course on “Probability and Statistics” in the Engineering Program at Polytech' Nice-Sophia (48H).

gave a 4H course in the
*IEEE Winter School on Information and Coding*(March 12–16, 2007, La Colle-sur-Loup, France).

taught a course on Dynamic Programming within the Mathematics Master Program at the University of Nice Sophia Antipolis (18H).

taught courses in the Master in Informatics of the University of Montpellier II on Performance Evaluation (6H), “Quality of Service in Networks” (27H), Random Discrete Structures (27H) and Metrology and Quality of Services (68H). She participated in the course on “Communication and Networks” of the Master in Computer Science of the University of Montpellier II (30H).

participated as a “moniteur” in the course on “Networking and System Architecture” in the Bachelor Program on “Computer Science” at the IUT of Nice Sophia Antopolis (96H).

taught a course on “Random Discrete Structures” (12H), and one on “Metrology and Quality of Service for Networks” (12H), both in the Master in Computer Science of the University of Montpellier II. He was invited to give a short course on “Network Calculus” at the University of Valparaiso, Chile.

taught a course on the Performance Evaluation of Networks in the Master Program on “Networks and Distributed Systems” at the University of Nice Sophia Antipolis (24H).

taught a course on Computer Networks within the Bachelor Program on “Telecommunication Engineering” at the University of Palermo, Italy (50H).

attended the
*First*
Euro-Fgi
*International Conference on Network Control and Optimization*(Avignon, France, June 5–7, 2007).

gave presentations at WiOpt 2007 (
*Workshop on Modeling in Mobile Ad Hoc and Wireless Networks*, April 16–20, 2007, Limassol, Cyprus) including SPASWIN 2007 and WNC3 2007 one day workshops, Valuetools 2007 (
*2nd International Conference on Performance Evalauation Methodologies and Tools*, October 23-25, 2007, Nantes, France) including GameCom and SMCTools one day workshop, NetCoop 2007 (
*International Conference on Network Control and Optimization*, June 5–7, 2007, Avignon, France), and
*Stochastic Network Workshop*(July 4–6, 2007, Edinburg, UK).

gave presentations at the
*
EuroFGI
International Conference on Network Control and Optimization(NetCoop 2007 – Avignon, France, June 5–7, 2007) and at the
22nd European Conference on Operations Research(EURO XXII – Prague, Czech Republic, July 8–11, 2007).*

gave a presentation at the
*8th IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks*(WoWMoM 2007 – Helsinki, Finland, June 18–21, 2007).

gave presentations at the
*joint ED SFA and ED STIC Doctoral Colloquium*(Sophia Antipolis, May 10–11, 2007) and the
*20th International Teletraffic Congress*(ITC 2007 – Ottawa, Canada, June 17–21, 2007). He also attended the
*9th IEEE Information Theory Winter School*(La Colle sur Loup, France, March 12–16, 2007).

gave a presentation at the
*Performance 2007 Conference*(Cologne, Germany, October 2–5, 2007).

gave presentations at
*
EuroFGI
International Conference on Network Control and Optimization(NetCoop 2007 – Avignon, France, June 5–7, 2007), at the
Workshop on Socially and Biologically Inspired Wired and Wireless Networks(Bionetworks – Pisa, Italy, October 8, 2007), and at the
2nd International Conference on Bio-Inspired Models of Network, Information, and Computing Systems(BIONETICS 2007 – Budapest, Hungary, December 10–13, 2007).*