CONFLICT-FREE CHANNEL SET ASSIGNMENT FOR AN OPTICAL CLUSTER INTERCONNECTION NETWORK-BASED ON ROTATOR DIGRAPHS

Recently a class of scalable multi-star optical networks is proposed i n [2]. In this class of networks nodes are grouped into clusters. Each cluster employs a separate pair of broadcast and select couplers. The clusters are interconnected via fiber links according to a regular to pology. Self links are provided to enable connectivity among nodes in the same cluster if the cluster size is more than one. These networks can efficiently combine time and/or wavelength division with direct sp ace division. The key design issue for these networks is the optimal c onflict-free channel set assignment to the output clusters for a given cluster interconnection topology. Such conflict-free channel assignme nt problem has been studied for various cluster interconnection topolo gies [1, 2, 9-11]. In this paper, we propose the rotator digraph [5] a s the cluster interconnection topology as it possesses many attractive properties. We will give an optimal conflict-free channel set assignm ent for this new interconnection topology. (C) 1998-Elsevier Science B .V. All rights reserved.