Application of delta-star topology to multicast network

A significant percentage of traffic will be occupied by various kinds of mu lticast services, beginning with the broadcasting services in a B-ISDN. In order to reduce the traffic on transmission paths in multicast services, po int-to-multipoint connections are used, which are significantly different f rom the past point-to-point connections. Thus, it is necessary to study the network topology for the case in which multicast services and point-to-poi nt communications services coexist. On the other hand, the delta-star topol ogy has been proposed as a topology effective for enhancing the reliability of the point-to-point communications networks. Since this topology combine s the ring topology, which is advantageous for multicasting, and the star t opology, which is advantageous for point-to-point communications, this topo logy is considered to be effective for the case in which both services coex ist. In this paper, the network construction cost is evaluated for the case s in which various topologies such as the mesh, star, ring, multiring, and delta-star topologies are applied to communications networks in which multi cast services and point-to-point communications services coexist. It has be en found that the delta-star topology is optimal for many cases, regardless of the receiving probabilities or transmission bandwidth of various servic es, transmission path constructed network topologies, and so forth. (C) 200 0 Scripta Technica.