MESSY BROADCASTING IN MULTIDIMENSIONAL DIRECTED TORI

Abstract

In classical broadcast models, once a vertex receives the broadcast message, it sends the message out in such a way as to achieve the minimum possible broadcasting time. It is assumed either that there is a leader who coordinates the actions of all vertices during the broadcasting process, or that the vertices have a coordinated set of protocols which allow them to achieve minimum time broadcast for any originator. In the messy broadcast model, there is no leader, the vertices of the network do not know the starting time of the broadcast or the originator, the state of the whole scheme is unknown to any vertex, and the protocols are not coordinated. This model also describes a network with vertices that have small memories insufficient to store a set of coordinated protocols. In this paper, we continue the study of messy broadcasting and present the first results for directed graphs. We obtain exact values for and bounds on the messy broadcast times of multidimensional directed tori.