Mascotte is a joint team between Inria Sophia-Antipolis and the laboratory I3s (Informatique Signaux et Systèmes Sophia-Antipolis) which itself belongs to Cnrs (Centre National de la Recherche Scientifique) and Unsa (University of Nice-Sophia Antipolis).

MASCOTTE is a joint team between INRIA Sophia-Antipolis and the laboratory I3S (Informatique Signaux et Systèmes Sophia-Antipolis) which itself belongs to CNRS (Centre National de la Recherche Scientifique) and UNSA (University of Nice-Sophia Antipolis). Furthermore MASCOTTE is strongly associated with the center of research and development of France Télécom at Sophia-Antipolis via the CRC CORSO.

Its research fields are Simulation, Algorithmic, Discrete Mathematics and Combinatorial Optimization with applications to telecommunication or transportation networks.

In particular, MASCOTTE has developed in the last four years both theoretical and applied tools for the design of heterogeneous networks of various types (like WDM, SDH, ATM, wireless, satellites, ...).

On the one hand, the project aims to construct or design networks or communication algorithms. On the other hand, it also wants to build software simulators or to implement algorithms, but not to conceive protocols. The theoretical results can be applied to various situations and technologies.

The project uses tools and theory in the following domains: Discrete
Mathematics, Algorithmic, Combinatorial Optimization and Simulation.
Typically, a telecommunication network (or an interconnection network)
is modeled by a graph. A vertex may represent either a processor, a
router, a switch or a person, and an edge (or arc) a connection
between the elements represented by the vertices. We can add more
information both on the vertices (for example what kind of switch is
used, optical or not, number of ports, equipment cost) and on the
edges (weights which might correspond to length, costs, bandwidth,
capacities) or colors on paths etc. According to the application,
various models can be defined and they have to be specified. This
modeling part is an important task. To solve the problems, in some
cases we can find polynomial algorithms: for example a maximum set of
disjoint paths between two given vertices is by Menger's theorem equal
to the minimum cardinality of a cut and it can be determined in
polynomial time using graph theoretic tools or flow theory or linear
programming. On the contrary, determining whether in a directed graph
there exists a pair of disjoint paths, one from s_{1} to t_{1} and the
other from s_{2} to t_{2}, is an NP-complete problem, and so are all
the problems which aim to construct or minimize the cost of a network
which can realize certain traffic requests. On many problems, the
project works with a deterministic hypothesis (for example if a
connection fails it is considered as definitely and not
intermittently). The project aims to construct or design networks or
communication algorithms or to build software simulators or to
implement algorithms but not to conceive protocols. The theoretical
results can be applied to various situations and technologies.

For the last five years the project has chosen as main domain of application Telecommunication leaving the domain of parallel computing. The project has also applications in the domain of ''transportation''. However, note that there is some overlap between the two domains; in particular theoretical tools and also communication problems are not really different if one considers transportation or telecommunication networks. Inside the telecommunication domain the applications we consider are strongly dependent on the interest of the industrial partners with whom we collaborate. With France Télécom (and other partners) we have worked on the design of telecommunication backbone networks (either SDH/SONET, WDM, or ATM networks) and on various fault-tolerance (protection) problems (in particular in case of link failures) or grooming (grouping) of small traffic containers into bigger ones. We have also used the PROSIT simulation framework developed in the project both for applications to a road traffic simulator (in the OSSA E.U. project) or in the ASIMUT simulation environment for satellite telecommunication in particular with the CNES.

Prosit**Prosit uses object oriented techniques to
allow for efficient development of complex discrete event simulation
packages. It has been used as the simulation engine for the European
projects Hipertrans and Ossa, devoted to high performance
simulation of road traffic. It has also been at the heart of the Asimut simulation environment developed by Cnes (the French
National Space Centre) for satellite telecommunication systems
evaluation.**

**Licenses of Prosit have been sold to Cnes and to Dassault Data Systems.**

Mascopt

Mascopt is Open Source and intends to use the most standard technologies such as Java and xml format providing portability facilities. We finished to implement graph data structure, several basic algorithms working on graph and input/output classes. Mascopt also provides some graphical tools to display graph results. We are currently writing network packages and performing experiments on wdm networks . A first application has been released which computes on-board networks with fault tolerance which is described in section 6.3.

Discrete Event Simulation (DEVS) is a modeling formalism that was initially proposed by Conception and Zeigler in 1988 to specify discrete event systems. This formalism allows a hierarchical modeling of systems: on the one hand it allows the definition of atomic models for each system component and on the other hand, it provides a coupling formalism to associate atomic components and build higher level components that may then be used themselves as atomic components. N. Giambiasi of LSIS (Marseille) introduced a Generalization of this formalism, called G-DEVS (1999) that extends the modeling capabilities of the DEVS formalism. Mascotte initiated a cooperation with LSIS, the MOEDIG project (supported by an INRIA COLOR funding) in order to study the G-DEVS formalism benefits through an implementation in the PROSIT simulation framework .

Preliminary work has been done by P. Mussi and A. Schwing on methodologies to estimate road traffic by using instrumented vehicles, in complement of or instead of road sensors. This work will be carried out in 2005 in the framework of the MobiVIP project.

Designing a backbone network consists in computing paths for
each traffic unit and then in assigning resources along these paths.
The set of paths is chosen according to the technology, the protocol
or the quality of service constraints. For instance, optical backbones
use the wdm technology to take better advantage of the capacity
of the optical fibers often already installed. This is achieved
through multiplexing several wavelength channels onto the same
fiber. In wdm networks, the huge bandwidth available on an
optical fiber is divided into multiple channels. Each channel carries
bandwidth up to several gigabits per second. A minimum unit of
resource allocation is an optical channel, which consists of a path
and a wavelength assigned on each link along the path and is called a
*lightpath*. If wavelength translation is performed in optical
switching, then each channel may be assigned different wavelengths on
each link along the path; otherwise the wavelength continuity
constraint must be satisfied on all links along the path. Of course,
two lightpaths sharing a link must use different wavelengths on that
link.

In MASCOTTE we have studied the wavelength routing and coloring problem, the traffic grooming problem and the virtual network embedding problem (with application to atm networks) and other design problems for backbone telecommunication networks with SDH (Synchronous Digital Hierarchy) technology..

Efficient optical routing aims to minimize the number of different wavelengths used in the network but also the number of electronic/optical conversions (hops for lightpaths). Another way for reducing the cost of the network is to group the traffic in such a way that some units of traffic may share some optical channels.

We address the problem of traffic grooming in wdm rings or paths
with *All-to-All* uniform unitary traffic. The goal is to minimize
the total number of sonet add-drop multiplexers (adms)
required. We have shown that this problem corresponds to a partition
of the edges of the complete graph into subgraphs, where each subgraph
has at most C edges (where C is the grooming ratio) and where the
total number of vertices has to be minimized. In preceding work,
using tools of graph and design theory, we optimally solve the problem
for rings for practical values and infinite congruence classes of
values for a given C. In we solve the problem for
rings and C = 6. In we study the problem for paths.

In a WDM network we assign to a new request the best possible route (if it exists) without computing a new routing for all requests. Thus, after several modifications of the set of requests, that is after a sequence of arrivals and terminations of requests, the routing may become inefficient. Furthermore, the probability of rejecting new requests may increase, even if there exists a routing for this set of request. So it is interesting to change the routing from time to time to improve the use of the resources in the network.

Given a set of requests and 2 different routings R_{1} and R_{2} for
it, we want to find a set of modifications of the routing to go from
R_{1} to R_{2}, according to the following rules: (i) a request can use
its new route if it is available (ii) we can move the route of a
request to a temporary position at any time (iii) when a request uses a
temporary route, it uses it until it can reach its final route. Our
objective is thus to minimize the number of requests that are
simultaneously in a temporary position.

We have modeled the problem in and studied it on particular classes of graphs. In we have proved that the problem is in general NP-complete and give an approximation for planar graphs.

In , we study hardness results and approximation algorithms of
k-tuple
domination in graphs. The k-tuple domination problem is a generalization
of the dominating set problem in graphs in which each vertex of the graph
has to be dominated at least k times.
A main application to network purposes of k-tuple domination is for
*fault tolerance* or *mobility* in the following situations.
Each vertex of the graph models a node of the network and edges are
links. Node u can use a service (any read-only data base for
example) only if it is replicated on u or on a neighbor of
u. To ensure a certain degree of fault tolerance or to tolerate
mobility of nodes, one can imagine that any node u has in its
(closed) neighborhood at least k copies of this service available.
As each copy can cost a lot, the number of duplicated copies has
to be minimized. This is the problem we study.
In , we describe tight approximability and non-approximability
results for general graphs, graphs of constant degree
and p-claw free graphs.

When one wants to establish a multicast communication in a network, one
searches for a low-cost substructure to be dedicated to this
communication. Such a substructure must guarantee that a message can
be sent from every member of the multicast group to any other. If we
model the network by an undirected graph, this correspond to the
Steiner Tree Problem which is known to be NP-Hard. However, if the
multicast group consists of all the nodes of the networks, this is the
minimum spanning tree problem which is easy. However, lots of
networks may not be modelled by undirected graphs. For example, in an
ad-hoc network a node a may be powerful enough to send some message
to a node b while b is not powerful enough to do the converse. In
, networks are modelled by directed graphs and the multicast
group is the set of nodes of the networks. Hence we investigate the
minimum spanning strong subdigraph problem. This problem is known to
be NP-hard and the best known approximation algorithm of Vetta has
ratio 1.5. We give an approximation algorithm with ratio 1 + 2/n where is the stability number of the directed graph and n
is its number of vertices. Hence our algorithm is better than the one by
Vetta when n/4, that is when the digraph is dense.

Inside a telecommunication satellite, audio and video signals are routed through a switching network to amplifiers. Since it is impossible to repair a satellite, we choose to multiply the components that may be faulty, that is amplifiers and switches.

The first problem is to build a valid network which allows to route n
input signals, to n amplifiers (outputs),
arbitrarily chosen among n + k, and thus supporting k broken
amplifiers. Each switch has 4
links and the routes followed by the
signals must be disjoint. Thus for economical constraints, the
objective is to build valid networks having the minimum number of
switches.

Within the CRC CORSO with France Telecom, we have studied the problem of designing efficient strategies to provide Internet access using wireless devices. Typically, in one village several houses wish to access a gateway (a satellite antenna) and to use multi-hop wireless relay routing to do so.

On the one hand we have modeled the problem as follows. Each node
(representing a house) is able to communicate to nodes not too far away
(at distance at most d). On the other hand, there is interference between
nodes (at distance at most ). The distances can be measured either
in terms of euclidean distances or number of hops. In our first study
we have considered the special case where each node has one
information (message) he wants to transmit to (or analogously receive
from) the gateway (gathering problem). We have in particular obtained
the results for specific topologies like paths or grids. In
, we have considered the case where there is permanent
demand (systolic algorithms). That leads to the definition of a *call scheduling problem*. In such networks the physical space is a
common resource that nodes have to share, since concurrent
transmissions cannot be interfering. We study how one can satisfy
steady bandwidth demands according to this constraint. We show that it
can be relaxed into a simpler problem: The *call weighting*
problem, which is almost a usual multi-commodity flow problem, but the
capacity constraints are replaced by the much more complex notion of
non interference. Not surprisingly, this notion involves independent
sets, and we prove that the complexity of the call weighting problem
is strongly related to the one of the independent set problem and its
variants (max-weight, coloring, fractional coloring). The hardness of
approximation follows when the interferences are described by an
arbitrary graph. We refine our study by considering some particular
cases for which efficient polynomial algorithms can be provided: the
*Gathering* in which all the demand are directed toward the same
sink, and specific interference relations: namely those induced by the
dimension 1 and 2 Euclidean space, those cases are likely to be
the practical ones.

On the other hand, we have worked on the improvement of the norm 802.11b. In the case when all the stations see each other, we have studied a memory-based process where the stations automatically adapt to their environment to avoid too frequent emissions (which generates collisions) or too rare ones (which results in a loss of bandwidth). When the number of stations increases, the 801.11b norms makes the global capacity of the system tend to zero. In , we describe and study several alternatives, and we propose a solution where the total capacity of the system does not tend to zero but stays relatively high. Simulations show that this systems improves by 40% the capacity of the channel for 100 stations, and by 8% when the RTS/CTS mechanism is used. This study has opened the way to several developments in the CORSO contract.

In , we present new upper bounds on the approximation ratio
of the Minimum Spanning Tree heuristic for the basic problem on *Ad-Hoc Networks* given by the *Minimum Energy Broadcast Routing*
(MEBR) problem. In , we introduce a new analysis allowing to
establish a 7.6-approximation ratio for the 2-dimensional case, thus
significantly decreasing the previously known 12 upper bound (actually
corrected to 12.15 in ). We also extend our analysis to
any number of dimensions d2, obtaining a general approximation
ratio of 3^{d}-1. The improvements of the approximation ratios are specifically
significant in comparison with the lower bounds given by the kissing numbers,
as these grow at least exponentially with respect to d.
In , we introduce a new analysis allowing to establish a
6.33-approximation ratio in the 2-dimensional case, thus decreasing the
7.6 upper bound from .

Wireless sensor networks have recently posed many new system
building challenges. One of the main problems is energy
conservation since most of the sensors are devices with limited
battery life and it is infeasible to replenish energy via
replacing batteries. An effective approach for energy conservation
is scheduling sleep intervals for some sensors, while the
remaining sensors stay active providing continuous service. In
we consider the problem of selecting a set of active
sensors of minimum cardinality so that sensing coverage and
network connectivity are maintained. We show that the greedy
algorithm that provides complete coverage has an approximation
factor of (logn), where n is the number of sensor
nodes. Then we present algorithms that provide approximate
coverage while the number of nodes selected is a constant factor
far from the optimal solution.

The X-*rank* of a sensor s is the number of sensors whose
X-coordinate is less than the X-coordinate of s. In
we provide a
theoretical foundation for sensor ranking, in the case where some
sensors know their locations and other sensors determine their
*ranking* only by exchanging information. We show that in one
dimension we can solve the ranking problem in linear time. On the
other hand, the ranking problem is NP-hard in .

Some of the first routing algorithms for position-aware wireless networks used the Delaunay triangulation of the point-locations of the network nodes as the underlying connectivity graph. Later on these solutions were considered impractical because the Delaunay triangulation may in general contain arbitrarily long edges and because calculating the Delaunay triangulation may require a global view of the network. Many other algorithms were then suggested for geometric routing, often assuming random placement of network nodes for analysis or simulation. But as we show in , when the nodes are uniformly placed in the unit disk the Delaunay triangulation does not contain long edges, it is easy to compute locally and it is in many ways optimal for geometric routing and flooding.

Motivated by the study of sensor networks we consider the following problem in :

Throw n points independently and randomly onto the n vertices
of G. Remap the points on G such that the load of each
vertex is exactly 1, minimizing the maximal distance that any
point has to move (on G).

We call it the *Points and Vertices* problem. It may be viewed
as an extension of the classical *Balls into Bins* problem,
where m balls are thrown (independently and uniformly at random)
into n bins, by adding graph-structural properties to the bins
so that the bins become vertices and there is an edge between two
vertices if they are ``close'' enough.

The interest in the Points and Vertices problem arises from the
fact that it captures in a natural way the ``distance'' between
the *randomness* of throwing points (independently and
uniformly at random) onto the vertices of G, and the *order*
of the points being evenly balanced on G. The problem also has
important applications in several fields such as token
distribution, geometric matching, wireless communications and
robotics.

Satellites send information to receivers on earth, each of
which is listening on a frequency. Technically it is impossible to
focus the signal sent by the satellite exactly on receiver. So part of
the signal is spread in an area around it creating noise for the other
receivers displayed in this area and listening on the same frequency. A
receiver is able to distinguish the signal directed to it from the
extraneous noises it picks up if the sum of the noises does not become
too big, i.e. does not exceed a certain threshold T. The problem is to
assign frequencies to the receivers in such a way that each receiver
gets its dedicated signal properly. We investigate this problem in
the fundamental case where the noise area at a receiver does not
depend on the frequency and where the ``noise relation'' is symmetric
that is if a receiver u is in the noise area of a receiver v then
v is in the noise area of u. Moreover the intensity I of the noise
created by a signal is independent of the frequency and the receiver.
Hence to distinguish its signal from noises, a receiver must
be in the noise area of at most
receivers listening to signals on the same frequency.

Moreover, due to some practical reasons (as, for instance, the specific environment of a receiver), the frequency at each receiver must be chosen among a list of allowed ones for that receiver.

New technologies and the deployment of mobile and nomadic services naturally engender new route-discovery problems under changing conditions over dynamic networks. Unfortunately, the temporal variations in the topology of dynamic networks are hard to be effectively captured in a classical graph model. We used evolving graphs, which helps capture the dynamic characteristics of such networks, in order to show that computing different types of strongly connected components in dynamic networks is NP-complete, and investigated the concepts of journeys in Evolving Graphs, which captures both space and time constraints in routing problems .

We further investigated the connected components problem in dynamic networks with special topologies. In a dynamic setting, the topology of a network derives from the set of all the possible links, past and future. We proved that the strongly connected components problem is still NP-complete when the topology is composed of unit disc graphs and the nodes are placed on a grid . On the other hand, we also gave a polynomial-time algorithm, by dynamic programming, in order to compute a maximum strongly connected components when the topology is a tree .

One of the new challenges facing research in wireless networks is
the design of algorithms and protocols that are energy aware.
The *minimum-energy broadcast routing* problem,
which attracted a great deal of attention these past years,
is NP-hard, even for a planar static network. The best
approximation ratio for it is a solution proved to be within a
factor 12 of the optimal. One popular way of achieving this ratio is
based on finding a Minimum Spanning Tree of the static planar
network. We used the evolving graph combinatorial
model to prove that computing a Minimum Spanning Tree of a planar
network in the presence of *mobility* is
NP-Complete . We also gave a polynomial-time
algorithm to build a rooted spanning tree of a mobile network, that
minimizes the maximum energy used by any one node, thus maximizing
the life-time of a wireless communication network .

With the rapid developments in hardware technologies, distributed computing and the interconnected world became realities, and the term "communication" became central in computer science. Solving communication tasks under different circumstances is the topic of this textbook . It provides an introduction to the theory of design and the analysis of algorithms for the dissemination of information in interconnection networks, with a special emphasis on broadcast and gossip. The book starts with the classic telegraph and telephone communication modes and follows the technology up to optical switches. Despite the rigorous presentation, simplicity and transparency are the main learning features of this book. All ideas, concepts, algorithms, analyses and arguments are first explained in an informal way in order to develop the right intuition, and then they are carefully specified in detail. This makes the content accessible for beginners as well as specialists.

Orientations and colourings of graphs are related in different ways but the deepness of these relations is not well understood. One of the results relating orientations to colouring is the Gallai-Roy Theorem. It states that the chromatic number of a graph is the minimum over all its orientations of the order (number of vertices) of a longest path. In 1982, Laborde, Payan and Xuong formulated the following conjecture implying the Gallai-Roy Theorem: Every oriented graph contains a stable set intersecting every longest paths. In , we prove this result for oriented graphs with stability at most 2.

Another way to extend the Gallai-Roy Theorem is in terms of unavoidable
substructures of k-chromatic graphs. Indeed, this theorem easily
implies that every k-chromatic oriented graph contains a directed
path of length k. A natural problem is: what are the oriented
graphs that are contained in every k-chromatic oriented graphs?
Since k-chromatic graph may have girth (length of a smallest cycle)
as large as we want, such unavoidable oriented graphs must be oriented
trees (orientations of trees). Since the complete graph with k
vertices is the easiest k-chromatic graph, a first step is to
consider the unavoidability of oriented trees in tournaments
(orientation of complete graphs). Havet and Thomassé conjectured in
2001 that every oriented tree of order n with k leaves is
contained in every tournament of order n + k. In , we
prove that this conjecture is true if k = 3 and a stronger result: every
oriented tree (with one exception) of order n with 3 leaves is
contained in every tournament of order n + 1.

Let f and g be two functions from a finite set E into a set F.
If f and g never coincides (i.e. f(x)g(x) for all xE), we seek for the minimum number of (f, g)-independent sets to
cover E, where a set is (f, g)-independent if
f(I)g(I) = .
This problem may be transformed into an arc-colouring problem
of some graph. Hence, motivated by function theory, we study
the maximum value of the arc-chromatic number over the
digraphs in which a vertex has either outdegree at most k or indegree at
most l.

We studied integral 2-commodity flows in networks with a special characteristic, namely symmetry. Symmetric networks represent a generalization of optical telecommunication networks, in which optical links are composed by pairs of opposite unidirectional optical fibers. We showed that the Symmetric 2-Commodity Flow Problem is polynomial, by proving that the cut criterion is a necessary and sufficient condition for the existence of a solution. We also gave an efficient algorithm which requires only six simple flow computations . This result closed an open question in a surprising way, since it is known that the Integral 2-Commodity Flow Problem is NP-complete in most graph families.

We study a problem related to the search in an anonymous and unknown network. In this model the nodes of the network have only a local and partial knowledge of the network and therefore the search algorithm needs to be independent of the topology. The cost of the algorithm can be measured either by the completion time (expressed in number of rounds) or by the number of messages sent.

* Contrat de recherche externalisé (*cre

* Contrat de recherche collaborative (*crc

As mentioned earlier, we have a strong collaboration with France Télécom R&D inside the CRC CORSO. This means that some researchers of MASCOTTE on one side and engineers of France Télécom R&D on the other side work together on specified subjects approved by a ''Comité de pilotage''. Among these subjects we can cite the design of telecommunication networks, the study of fault tolerance and the use of radio networks for bringing Internet in places where there is no ADSL.

MobiVIP is a PREDIT project funded by Ministries of Research, Transportation, Industry and Environment, together with ANVAR and ADEME. In this program, 5 research laboratories and 7 SMEs work in collaboration to experiment, demonstrate and evaluate a new transportation system for cities, based on intelligent small urban vehicles. Mascotte will develop methods for traffic estimation based on instrumentation of those vehicles.

* Atip jeunes chercheurs *Cnrs

**Aci sécurité: ``**Presto**''**, 2003- 2006, on
survivability of communication networks, in collaboration with the
enst (Paris) and the limos (Clermont-Ferrand).

**European project RTN: ``**Aracne**''**, 2000-2004, on
Approximation and Randomized Algorithms for Communication Networks,
in collaboration with the universities of Salerno (coordinator) and
Roma (Italy), Patras (Greece), Geneva (Switzerland) and Kiel
(Germany). The goal of this project is to study communication
problems and network designs from the algorithmic side.

**European project Ist : ``**Crescco**''**, 2002-2005, on
critical resource sharing for cooperation in complex systems, in
collaboration with the universities of Salerno and Roma (Italy),
Patras (Greece, coordinator), Geneva (Switzerland) and Kiel (Germany).
Mascotte works essentially on the efficient use of bandwidth in WDM
networks (Workpackage 4).

**European COST Action: "**COST 293, Graal**"**, 2004-2008.
The main objective of this COST action is to elaborate global and
solid advances in the design of communication networks by letting
experts and researchers with strong mathematical background meet peers
specialized in communication networks, and share their mutual
experience by forming a multidisciplinary scientific cooperation
community. This action has more than 25 academic and 4 industrial
partners from 18 European countries. Mascotte works essentially on
the design and efficient use of optical backbone network.

P. Mussi has joined COST Action 355 **"Changing behaviour towards a more
sustainable transport system"**.
The main objective of this COST Action is to develop a more rigorous understanding
of the conditions under which the process of growing unsustainable transport
demand could be reversed, by changing travellers , shippers and carriers
behaviour.

**Proposal of a Network of Excellence: ``**Saga**''**, 2003, on
structural and algorithmic aspects of communication networks, in
collaboration with 51 European research centers and 28 European
companies. Unfortunately, this proposal has not been accepted; but it
has strengthened the collaboration between various groups in Europe and
there was a successful workshop and the proposal will be resubmitted.

**Funds are given by the ministry to pursue this collaboration in 2004.**

**Cooperation **Cnrs**–Oxford**, 2003-2005, on frequency
allocation problems in wireless networks, in collaboration with the
Mathematical Institute of Oxford University.

Funded by the Paca province.

Bilateral Cooperation, 04/2004-03/2006, on ``Web Graphs and Web Algorithms'', in collaboration with the Department of Computer Science, King's College London.

Funded by the Royal Society, U.K.

**Cooperation **Inria**–Brazil: ``**Regal**''**, 2003-2006, on
algorithmic problems for telecommunication networks, in collaboration
with the Federal University of Ceara (Fortaleza, Brazil).

Funded by the Paca province (06/04-06/06).

One of the main objectives is to strengthen our collaboration with sfu. Many reciprocal visits have been performed.

(http://www-sop.inria.fr/mascotte/David.Coudert/EquipeAssociee/)

*Louigi Addario-Berry*, McGill University (Canada), 20/09/04 - 01/10/04.

*Victor Almeida-Campos*, University of Fortaleza (Brazil), 03/03/04 - 01/04/04.

*Colin Cooper*, King's College London (UK), 21/11/04 -26/11/04.

*Ricardo Correa*, University of Fortaleza (Brazil), 02/11/04 -
29/11/04.

*Alfredo Goldman*, University of Sao Paolo (Brésil), 01/10/04 - 09/10/04.

*Pavol Hell*, Simon Fraser University (Canada), 07/11/04 - 20/11/04.

*Ross Kang*, Oxford University (UK), 27/09/04 - 12/10/04.

*Evripides Markou*, University of Athens (Greece), 15/11/04 - 24/11/04.

*Joseph Peters*, Simon Fraser University (Canada), 12/05/04 -
19/07/04.

*Tomasz Radzik*, King's College London (UK), 19/04/04 -
24/04/04 and 04/10/04 - 03/12/04.

*Fabiano Sarracco*, University of Roma (Italy), 08/11/04 -
25/03/05.

*Joseph Yu*, Simon Fraser University (Canada), 01/02/04 - 30/04/04 and 14/06/04 - 30/06/04.

*J.-C. Bermond*: Fortaleza (Brazil) 17/01/04-09/02/04, CTI
Patras (Greece) 05-21/06/04, S.F.U. Vancouver (Canada)
24/08/04-1/10/04.

*D. Coudert*: S.F.U. Vancouver (Canada) 16/08/04-17/09/04.

*A. Ferreira*: Sao Paolo and Fortaleza (Brazil) 09/02/04-07/03/04.

*R. Klasing*: S.F.U. Vancouver (Canada) 31/01/04-28/02/04,
King's College London (UK) 25/07/04-01/08/04.

*J-F. Lalande*: Kiel (Germany) 11-25/05/04.

*A. Laugier*: Otto von Guericke University, Magdeburg (Germany) 11/04.

*A. Navarra*: L'Aquila (Italy) and Athens (Greece) 03-29/05/04.

*S. Pérennes*: L'Aquila (Italy) 01-30/11/04.

*H. Rivano*: DISI, Genova (Italy) 01/03/04-01/06/04 (part time).

*M. Syska*: Kiel (Germany) 11-25/05/04, S.F.U. Vancouver
(Canada) 16/08/04-17/09/04.

*J-C. Bermond*: expert for Rnrt; member of the
scientific committee of LIRMM (Montpellier); member of the
"Commission de Spécialistes de la 27^{e} section" of Unsa;
substitute member of the "Commissions de Spécialistes de la
27^{e} section" of UTC (université de Technologie de Compiègne)
and Université de la Méditerranée (Aix-Marseille II); member of the
I3s Project Commitee; nominated member of the RTP (réseaux
thématiques) Commitee of STIC department " Réseaux " and
" Mathématiques de l'Informatique "; member of the PhD committee
of Marseille and of the "Conseil Scientifique" of the Ecole
Doctorale STIC of Nice-Sophia antipolis.

*M. Cosnard* : chair of the ACI Grid ; substitute member
of the Commission de Spécialistes 27^{e} section of Ens Lyon ;
chair of the conseil scientifique of Cines.

*D. Coudert*: secretary for the INRIA Sophia Antipolis
Project Committee until April 04; secretary substitute afterward;
member of the COST Action 293 Management Committee.

*O. Dalle *: member of working group "Vers une théorie de la
Simulation" (http://www.lsis.org/versim/), member of the ``Commission
de Spécialistes 27^{e} section'' of Unsa, member of the ``Commission
du Développement Logiciel'' de l'INRIA Sophia Antipolis, member of the ``Comité
Informatique'' of I3S.

*A. Ferreira*: nominated member of the I3S laboratory
Commitee; member of the "Commission d'évaluation" of the INRIA; member
of the RNRT commission 3; member of the CNRT Telius board.

*J. Galtier*: member of the COST Action 293 Management Committee.

*F. Havet*: member of the I3S laboratory Committee, of the "Commission de
Spécialistes de la 25^{e} et 26^{e} section" of the University of Lyon 1,
and of the "Commission de Spécialistes de la 27^{e} section" of
the University of Montpellier II.

*R. Klasing*: substitute member of the I3S laboratory Committee.

*A. Laugier*: refeeree for ACI "Nouvelles interfaces des mathématiques".

*P. Mussi*: head of the ReV department (public relations,
international and industrial partnerships) of INRIA Sophia Antipolis, member
of the "Commission de Spécialistes de la 27^{e} section" of University of
Nice-Sophia Antipolis, member of working group "Modélisation Multiple et
Simulation" (GdR MACS, http://mad3.univ-bpclermont.fr/), and working
group "Vers une théorie de la Simulation"
(http://www.lsis.org/versim/).

*M. Syska*: nominated member of the I3S laboratory Committee
as president of "Commission informatique".

*J-C. Bermond*: Combinatorics Probability and Computing,
Discrete Mathematics, Discrete Applied Mathematics, Journal of Graph
Theory, Journal Of Interconnection Networks (Advisory Board),
Mathématiques et Sciences Humaines, Networks, Parallel Processing
Letters and the Siam book series on Discrete Mathematics.

*M. Cosnard*: Editor-in-Chief of Parallel Processing
Letters. Member of the Editorial Board of Parallel Computing, of
Theory of Computational Systems (TOCS) and of IEEE TPDS.

*A. Ferreira*: Journal of Parallel and Distributed
Computing (Academic Press), Parallel Processing Letters (World
Scientific), Parallel Algorithms and Applications (Elsevier),
Journal of Interconnection Networks (World Scientific).

*M. Cosnard*: SPAA - *Symposium on Parallel Algorithms
and Architectures* (2001-2004), PACT (Chair) *Parallel Computing
Technologies* (2002-2005) - IFIP Working Group 10.3.

*A. Ferreira*: AlgoTel, Ecotel, DialM.

*D. Coudert, O. Dalle and E. Deriche* organized the 6th Winter
School on Telecommunications (EcoTel'04), 2-9/12/04, Zarzis, Tunisia.

*A. Ferreira*: CLADE, WCSF, WWAN.

*F. Havet*: co-chair of ALGOTEL 2004.

*J. Galtier*: Networking 2004.

*A. Laugier*: Graph Theory 2004.

*P. Mussi*: CSM04, PDCN 2004, Majecstic'04.

The following theses have been passed in 2004:
*J.-F. Lalande*: Conception de réseaux de télécommunications :
optimisation et expérimentations, ESSI, December 10th;

The following theses are in preparation:

*G. Huiban*: La reconfiguration dans les réseaux optiques multifibres;

*A. Jarry*: Connexité et protection dans les réseaux de
télécommunications;

*N. Morales*: Méthodes d'approximation pour les problèmes de
réseaux de télécommunications avec de contraintes économiques et de
traffic incertain;

*S. Petat*: Contraintes de couplages pour la conception de
réseaux de télécommunications;

*J-S. Sereni*: Coloration par listes appliquée à
l'allocation de fréquences;

*M-E. Voge*: Protection et groupage dans les réseaux de
télécommunications.

*J-C. Bermond and M. Syska*: members of the Ph.D. Committee of J-F.
Lalande (University of Nice-Sophia Antipolis).

*R. Klasing*: External Ph.D. reviewer of P. Chen (S.F.U.,
06/08/04), member of the Ph.D. Committee of C. Destré (University of
Evry, 06/12/04).

*M. Cosnard*: member of many Ph.D. and HdR Committees.

*R. Klasing* supervised the preDoc internship of Fabiano
Saracco (University of Roma)

*D. Coudert* supervised the internship of Laurent Braud
(Ens Lyon)

*D. Coudert* supervised the internship of Quang Cuong Pham
(Ens Ulm)

*D. Coudert* supervised the master of Arnaud Daver (DEA RSD)

*H. Rivano* supervised the internship of Laurent Jouhet
(Ens Lyon)

*D. Coudert* supervised the master of Marc Martinez de
Albeniz (UPC Barcelona)

*D. Coudert and M. Syska* supervised the internship of
Claudine Mossé (IUP Avignon)

*J. Galtier* supervised the master of Ludovic Samper (DEA
MDFI, Marseille)

*J-C. Bermond and S. Pérennes* supervised the internship of
Jeremy Serror (Magistère Paris VII)

*P. Mussi* supervised the master of Alejandro Acosta (Master
ENST Bretagne)

*P. Mussi* supervised the master of Alexandre Schwing
(Master Ecole Polytechnique Marseille)

*M. Syska* is supervising the project of Yves Baumes and
Benjamin Nosenzo (essi).

The members of MASCOTTE strongly participate in a lot of teaching activities in undergraduate studies (DEUG, IUT, Licence Maîtrise, Engineering Schools like ESSI). The teaching is insured by members of the University as their teaching duties and for INRIA CNRS or PhD's as extra work. It represents more than 1000 hours per year.

For graduate studies, MASCOTTE was strongly involved in the creation of the DEA RSD (Réseaux and Systèmes Distribués) and now members of MASCOTTE teach both in the mandatory lectures and in 3 options of the DEA RSD. Members of MASCOTTE are also involved in teaching in other DEA's like the DEA MDFI of Marseille or in DESS like the DESS Telecoms or in the 3rd year of engineering schools. Altogether that represents around 200 hours per year.

The members of MASCOTTE supervise on the average around 20 internships per year at all levels (Maîtrise, Engineering School, DEA). The students come from various places in France as well as from abroad (e.g. Europe, Chile, United States, India). Some of the internship reports are listed in the bibliography under the heading miscellaneous.

*J-S. Sereni*: LaPCS, Lyon, January 21st.

*R. Klasing*: Network Modeling Group seminar, S.F.U.,
Vancouver, Canada, February.

*M. Syska*: Research Group Discrete Optimization, Kiel,
Germany, May 18th.

*F. Havet*: LIRMM, Montpellier, July 1st.

*A. Jarry*: Operations Research 2004, Tilburg, Netherland,
September 1-3rd.

*M. Syska*: NMG seminar, S.F.U.,
Vancouver, Canada, September 10th.

*J-C. Bermond*: NMG seminar, S.F.U.,
Vancouver, Canada, September.

*F. Havet*: LaBRI, Bordeaux, December 3rd.

*S. Bessy*: Ecole Polytechnique de Lausanne, Switzerland, December
16th.

*P. Mussi* attended the MobiVIP kickoff meeting, Paris, January 15th.

*A. Ferreira and R. Klasing* attended the CRESCCO and ARACNE
2 preparation meeting, Roma, Italy, January 19-20th.

*J-F. Lalande* attended "Rencontres INRIA-Industrie",
Rocquencourt, January 27th.

*P. Mussi* attended the Versim working group meeting, Marseille, February 9th.

*P. Mussi* attended the MMS working group meeting, Villeurbanne, February 13th.

*M. Syska* attended the RTP "Réseaux de Communication",
Carcassonne, April 8-9th.

*P. Mussi and O. Dalle* attended the Versim working group meeting, Montpellier,
May 11th.

*J-S. Sereni* attended "Deuxième Journée de Combinatoire
Rhônes-Alpes", Grenoble, May 19th.

*D. Coudert, J. Galtier, J-F. Lalande, A. Laugier, S. Petat
and M-E. Voge* attended the "Optimization Seminar of France Telecom
R&D", Sophia Antipolis, June 2-4th.

*D. Coudert and S. Perennes* attended the CRESCCO meeting,
Athens, Greece, July 26-27th.

*J-C. Bermond, D. Coudert, J-F. Lalande, H. Rivano,
M-E. Voge* attended the meeting of the Aci PRESTO,
Clermont-Ferrand, October 4th.

*D. Coudert, A. Jarry, R. Klasing, J-F. Lalande, N. Morales,
H. Rivano and M-E. Voge* attended the TAROT meeting, Lyon, October
14-15th.

*D. Coudert* attended the COST Action 293 kick off meeting,
Brussels, Belgium, October 20th.

*D. Coudert and H. Rivano* attended the ACI-SI meeting,
Toulouse, November 15-17th.

*P. Mussi* attended Cost 355 meeting, Namur, December 1-2nd.

*D. Coudert and M. Syska* attended Global Computing'04,
Trento, Italy, March 8-10th.

*A. Jarry* attended WiOpt'04, Cambridge, UK, March 24-26th.

*A. Jarry* attended STACS'04, Montpellier, March 25-27th.

*D. Coudert and F. Havet* attended AlgoTel'04, Batz-sur-Mer,
May 26-28th.

*A. Navarra* attended Networking 2004, Athens, Greece, May
9-14th.

*G. Huiban* attended Optimization 2004, Lisbon, Portugal,
May 25-28th.

*J-F. Lalande* attended JNPC'04, Anger, June 21-23th.

*M-E. Voge* attended the First Workshop on Algorithms for
Scheduling and Communication, Bertinoro, Italy, 27/06/04-03/07/04.

*F. Havet, J. Galtier, A. Laugier and J-S. Sereni* attended GT'2004,
Paris, July 5-9th.

*J. Galtier* attended ITC Specialist Seminar 2004,
Antwerpen, Belgium, 31/08/04-02/09/04.

*A. Jarry* attended DIALM-POMC 2004, Philadelphia, USA,
October 1st.

*J-C. Bermond and M. Syska* attended the CRESCCO meeting and workshop, Roma, Italy, October 16th.

*D. Coudert, E. Deriche, G. Huiban, J-F. Lalande, N. Morales, P.
Mussi, H. Rivano, J-S. Sereni and M-E. Voge * attended the the 6th Winter School
on Telecommunications (EcoTel'04), 2-9/12/04, Zarzis, Tunisia.