On-Line Distributed Traffic Grooming

This paper addresses the problem of on-line traffic grooming in WDM paths. Each request consists of a source node, a destination node, and the desired bandwidth for the connection. Connections may be multi-hop, permitting the use of multiple lightpaths. We describe a new distributed on-line algorithm for this problem that is provably wide-sense non-blocking under cer- tain assumptions. Moreover, we use simulations to demonstrate that the algorithm is extremely effective even when some of these assumptions are relaxed

Evolution of Genes Neighborhood Within Reconciled Phylogenies: An Ensemble Approach

Context The reconstruction of evolutionary scenarios for whole genomes in terms of genome rearrangements is a fundamental problem in evolutionary and comparative genomics. The DeCo algorithm, recently introduced by Bérard et al., computes parsimonious evolutionary scenarios for gene adjacencies, from pairs of reconciled gene trees. However, as for many combinatorial optimization algorithms, there can exist many co-optimal, or slightly sub-optimal, evolutionary scenarios that deserve to be considered. Contribution We extend the DeCo algorithm to sample evolutionary scenarios from the whole solution space under the Boltzmann distribution, and also to compute Boltzmann probabilities for specific ancestral adjacencies. Results We apply our algorithms to a dataset of mammalian gene trees and adjacencies, and observe a significant reduction of the number of syntenic conflicts observed in the resulting ancestral gene adjacencies