The steiner problem with edge lengths 1 and 2,
Information Processing Letters
When Trees Collide: An Approximation Algorithm for theGeneralized Steiner Problem on Networks
SIAM Journal on Computing
A General Approximation Technique for Constrained Forest Problems
SIAM Journal on Computing
Multicast tree generation in networks with asymmetric links
IEEE/ACM Transactions on Networking (TON)
On-line algorithms for Steiner tree problems (extended abstract)
STOC '97 Proceedings of the twenty-ninth annual ACM symposium on Theory of computing
Online computation and competitive analysis
Online computation and competitive analysis
On-line generalized Steiner problem
Proceedings of the seventh annual ACM-SIAM symposium on Discrete algorithms
Approximation algorithms for directed Steiner problems
Journal of Algorithms
Improved Steiner tree approximation in graphs
SODA '00 Proceedings of the eleventh annual ACM-SIAM symposium on Discrete algorithms
On the approximability of the Steiner tree problem
Theoretical Computer Science - Mathematical foundations of computer science
The greedy, the naive, and the optimal multicast routing: from theory to internet protocols
The greedy, the naive, and the optimal multicast routing: from theory to internet protocols
A Near-Tight Bound for the Online Steiner Tree Problem in Graphs of Bounded Asymmetry
ESA '08 Proceedings of the 16th annual European symposium on Algorithms
Online Priority Steiner Tree Problems
WADS '09 Proceedings of the 11th International Symposium on Algorithms and Data Structures
On the competitiveness of the online asymmetric and euclidean steiner tree problems
WAOA'09 Proceedings of the 7th international conference on Approximation and Online Algorithms
| Hi-index | 0.00 |
In this paper we consider the Online Steiner Tree problem in weighted directed graphs of bounded edge-asymmetry α. The edge-asymmetry of a directed graph is defined as the maximum ratio of the cost (weight) of antiparallel edges in the graph. The problem has applications in multicast routing over a network with non-symmetric links. We improve the previously known upper and lower bounds on the competitive ratio of any deterministic algorithm due to Faloutsos et al. [11]. In particular, we show that a better analysis of a simple greedy algorithm yields a competitive ratio of O (min {k, α log k/log log α}), where k denotes the number of terminals requested. On the negative side, we show a lower bound of Ω(min{k1-ε, α log k/log log k}) on the competitive ratio of every deterministic algorithm for the problem, for any arbitrarily small constant ε.