Combinatorica
Expanders, randomness, or time versus space
Journal of Computer and System Sciences - Structure in Complexity Theory Conference, June 2-5, 1986
Architectures for linear lightwave networks
Architectures for linear lightwave networks
Efficient routing in all-optical networks
STOC '94 Proceedings of the twenty-sixth annual ACM symposium on Theory of computing
Routing and wavelength assignment in all-optical networks
IEEE/ACM Transactions on Networking (TON)
All-optical networks with sparse wavelength conversion
IEEE/ACM Transactions on Networking (TON)
Efficient routing in optical networks
Journal of the ACM (JACM)
Adaptive wavelength routing in all-optical networks
IEEE/ACM Transactions on Networking (TON)
STOC '98 Proceedings of the thirtieth annual ACM symposium on Theory of computing
Multiwavelength optical networks with limited wavelength conversion
IEEE/ACM Transactions on Networking (TON)
Optimal wavelength routing on directed fiber trees
Theoretical Computer Science
Improved bounds for all optical routing
Proceedings of the sixth annual ACM-SIAM symposium on Discrete algorithms
Improved access to optical bandwidth in trees
SODA '97 Proceedings of the eighth annual ACM-SIAM symposium on Discrete algorithms
Ring routing and wavelength translation
Proceedings of the ninth annual ACM-SIAM symposium on Discrete algorithms
Wavelength conversion in optical networks
Proceedings of the tenth annual ACM-SIAM symposium on Discrete algorithms
On optiml converter placement in wavelength-routed networks
IEEE/ACM Transactions on Networking (TON)
Efficient collective communication in optical networks
Theoretical Computer Science
On the Complexity of Wavelength Converters
MFCS '98 Proceedings of the 23rd International Symposium on Mathematical Foundations of Computer Science
Colouring Paths in Directed Symmetric Trees with Applications to WDM Routing
ICALP '97 Proceedings of the 24th International Colloquium on Automata, Languages and Programming
Limited Wavelength Conversion in All-Optical Tree Networks
ICALP '98 Proceedings of the 25th International Colloquium on Automata, Languages and Programming
Efficient Wavelength Routing on Directed Fiber Trees
ESA '96 Proceedings of the Fourth Annual European Symposium on Algorithms
Efficient access to optical bandwidth
FOCS '95 Proceedings of the 36th Annual Symposium on Foundations of Computer Science
Tight bounds for depth-two superconcentrators
FOCS '97 Proceedings of the 38th Annual Symposium on Foundations of Computer Science
Graphs and Hypergraphs
Limited-range wavelength translation in all-optical networks
INFOCOM'96 Proceedings of the Fifteenth annual joint conference of the IEEE computer and communications societies conference on The conference on computer communications - Volume 3
Models of blocking probability in all-optical networks with and without wavelength changers
IEEE Journal on Selected Areas in Communications
Benefits of wavelength translation in all-optical clear-channel networks
IEEE Journal on Selected Areas in Communications
Wavelength conversion in WDM networking
IEEE Journal on Selected Areas in Communications
Optimal bandwidth utilization of all-optical ring with a converter of degree 4
Journal of Computer Science and Technology
Bandwidth allocation in WDM tree networks
IPDPS '01 Proceedings of the 15th International Parallel & Distributed Processing Symposium
On Shortest-Path All-Optical Networks without Wavelength Conversion Requirements
STACS '03 Proceedings of the 20th Annual Symposium on Theoretical Aspects of Computer Science
Recent Advances in Wavelength Routing
SOFSEM '01 Proceedings of the 28th Conference on Current Trends in Theory and Practice of Informatics Piestany: Theory and Practice of Informatics
Multicast connection capacity of WDM switching networks with limited wavelength conversion
IEEE/ACM Transactions on Networking (TON)
Routing to reduce the cost of wavelength conversion
Discrete Applied Mathematics
Hi-index | 5.23 |
We study the problem of assigning a minimum number of colors to directed paths (dipaths) if a tree, so that any two dipaths that share a directed edge of the tree are not assigned the same color. The problem has applications to wavelength routing in WDM all-optical tree networks, an important engineering problem. Dipaths represent communication requests, while colors correspond to wavelengths that must be assigned to requests so that multiple users can communicate simultaneously through the same optical fiber. Recent work on wavelength routing in trees has studied a special class of algorithms which are called greedy. Although these algorithms are simple and implementable in a distributed setting, it has been proved that there are cases where a bandwidth utilization of 100% is not possible. Thus, in this work, we relax the constraints of the original engineering problem and use devices called wavelength converters that are able to convert the wavelength assigned to a segment of a communication request to another wavelength that will be assigned to some other segment of the same request. The trade-off of the use of wavelength converters is increased cost and complexity; so, our aim is to use converters that have relatively simple functionality. We study the performance of greedy deterministic algorithms in tree-shaped all-optical networks that support wavelength conversion. We study both the case of sparse conversion and limited conversion. By sparse we mean that converters have full conversion capabilities and the objective is to minimize the number of converters employed. On the other hand, in limited conversion, we assume that converters with limited conversion capabilities are placed at each non-leaf node of the tree. By limited, we mean that converters are simple according to either their wavelength degree or their size. Our results show that using converters of either low degree or small size, we can beat the known lower bounds and improve bandwidth utilization. In some cases we even achieve optimal bandwidth utilization. For the construction of the converters, we use special classes of graphs such as expanders, dispersers and depth-two superconcentrators. Explicit constructions are known for most of the graphs used in this paper. Copyright 2001 Elsevier Science B.V.