BEAUQUIER , Bruno

This thesis is mainly devoted to the study of "communication in wavelength multiplexed optical networks", from which arise algorithmic and graph theoretic problems. The main issue in WDM (Wavelength Division Multiplexed) all-optical communication networks can be stated as follows. Connection requests between pairs of source-destination network...

The well-known spanning binomial tree broadcast algorithm is generalized to obtain two families of broadcast algorithms for optical rings and two-dimensional toroidal meshes (tori) using {\em Wavelength Division Multiplexing (WDM)}. These generalizations take advantage of the concurrent transmission through optical links offered by WDM. Their...

This paper studies the problem of All-to-All Communication for optical networks. In such networks the vast bandwidth available is utilized through wavelength division multiplexing (WDM) : a single physical optical link can carry several logical signals, provided that they are transmitted on different wavelengths. In this paper we consider...

Motivated by problems in telecommunication satellites, we investigate rearrangeable permutation networks made of binary switches. A simple counting argument shows that the number of switches necessary to build a $n \times n$ rearrangeable network (i.e. capable of realizing all one-to-one mappings of its $n$ inputs to its $n$ outputs) is at...

International audience

Motivated by wavelength division multiplexing in all-optical networks, we consider the problem of finding a set of paths from a fixed source to a multiset of destinations, which can be coloured by the fewest number of colours so that paths of the same colour do not share an arc. We prove that this minimum number of colours is equal to the...

This work considers broadcast protocols made of successive communication rounds in the linear cost model: the time needed to send a message of length L is defined as \alpha +L\tau. In this model, the communication time of any algorithm \mathcal{A} is expressed as the sum R_\mathcalA\cdot\alp- ha +T_\mathcal{A} \cdot\tau, where R_\mathcalA is...

A tree of rings is an undirected graph obtained from the union of rings, which intersect two by two in at most one node, such that any two nodes are connected by exactly two edge-disjoint paths. In this paper, we consider symmetric directed trees of rings with weighted nodes. A routing for a weighted digraph is a collection of directed paths...

This paper surveys the theoretical results obtained for wavelength{routing all{optical networks, presents some new results and proposes several open problems. In all{optical networks the vast bandwidth available is utilized through wavelength division multiplexing: a single physical optical link can carry several logical signals, provided that...

We survey the theoretical results obtained for wavelength routing in all--optical networks, present some new results and propose several open problems. In all--optical networks the vast bandwidth available is utilized through {\em wavelength division multiplexing}~: a single physical optical link can carry several logical signals, provided that...