Efficient routing in all-optical networks
STOC '94 Proceedings of the twenty-sixth annual ACM symposium on Theory of computing
A note on optical routing on trees
Information Processing Letters
All-to-all routing and coloring in weighted trees of rings
Proceedings of the eleventh annual ACM symposium on Parallel algorithms and architectures
Optimal wavelength routing on directed fiber trees
Theoretical Computer Science
Ring routing and wavelength translation
Proceedings of the ninth annual ACM-SIAM symposium on Discrete algorithms
The complexity of path coloring and call scheduling
Theoretical Computer Science
Maximizing the Number of Connections in Optical Tree Networks
ISAAC '98 Proceedings of the 9th International Symposium on Algorithms and Computation
Efficient access to optical bandwidth
FOCS '95 Proceedings of the 36th Annual Symposium on Foundations of Computer Science
Approximation algorithms for disjoint paths problems
Approximation algorithms for disjoint paths problems
Call Control with k Rejections
SWAT '02 Proceedings of the 8th Scandinavian Workshop on Algorithm Theory
On-line Algorithms for Edge-Disjoint Paths in Trees of Rings
LATIN '02 Proceedings of the 5th Latin American Symposium on Theoretical Informatics
Tight Bounds for Wavelength Assignment on Trees of Rings
IPDPS '05 Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Papers - Volume 01
Wavelength assignment for satisfying maximal number of requests in all-optical networks
AAIM'05 Proceedings of the First international conference on Algorithmic Applications in Management
Approximation algorithms for edge-disjoint paths and unsplittable flow
Efficient Approximation and Online Algorithms
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A tree of rings is a network that is obtained by interconnecting rings in a tree structure such that any two rings share at most one node. A connection request (call) in a tree of rings is given by its two endpoints and, in the case of prespecified paths, a path connecting these two endpoints. We study undirected trees of rings as well as bidirected trees of rings. In both cases, we show that the path packing problem (assigning paths to calls so as to minimize the maximum load) can be solved in polynomial time, that the path coloring problem with prespecified paths can be approximated within a constant factor, and that the maximum (weight) edge-disjoint paths problem is NP-hard and can be approximated within a constant factor (no matter whether the paths are prespecified or can be determined by the algorithm). We also consider fault-tolerance in trees of rings: If a set of calls has been established along edge-disjoint paths and if an arbitrary link fails in every ring of the tree of rings, we show that at least one third of the calls can be recovered if rerouting is allowed. Furthermore, computing the optimal number of calls that can be recovered is shown to be polynomial in undirected trees of rings and NP-hard in bidirected trees of rings.