Communications in a multicomputer system consist of heterogeneous traffic in which messages exhibit a variety of sizes.Network response is highly dependent on message length distribution, as reported in most network evaluation studies.Hence, router design should be optimized for dealing with heterogeneous traffic.This study analyzes the interaction amongst short and long messages in networks with bimodal length traffic: both single packet traffic (20 flits) and multipacket messages (200 flits).Router design determines the access of both traffic classes to the network resources so we have considered multiple alternatives, from the generic CT or WH static router to variations of the segment router proposed in [9], which maps the two traffic classes into two separate virtual networks.Having independent injection queues for each virtual network and adjusting the channel multiplexing policy to favour short or long messages provides good performance and added flexibility when compared to its cut-through counterpart.

The use of telecommunications to overcome the isolation of disabled people is analyzed. In order to use these kinds of services, such abilities as hearing and vision are necessary. Any lack of these abilities must be compensated for with technical aids to allow these people to have an independent and productive life. Experience in this field is described, and different efforts in Europe toward integration of disabled people into society by using modern telecommunication services are outlined.>

The authors introduce and study a family of interconnection schemes, the Midimew networks, based on circulant graphs of degree 4. A family of such circulants is determined and shown to be optimal with respect to two distance parameters simultaneously, namely maximum distance and average distance, among all circulants of degree 4.. These graphs are regular, point-symmetric, and maximally connected, and one such optimal graph exists for any given number of nodes. The proposed interconnection schemes consist of mesh-connected networks with wrap-around links, and are isomorphic to the optimal distance circulants previously considered. Ways to construct one such network for any number of nodes are shown, their good properties to build interconnection schemes for multicomputers are examined, and some interesting particular cases are discussed. The problem of routing is also addressed, and a basic algorithm is provided which is adequate for implementing the routing policy required to convey messages, traversing shortest paths between nodes.>