An optimal scheduling for file dissemination under a full binary tree of trust relationship

In network applications with security constraints, it is usually desirable to disseminate a file from a server through trusted network channels to a set of peers. This is a problem seldom studied in the literature though the problems of data integrity and security have been studied by many. In this paper, we study the file dissemination problem with trust relation modeled as a rooted full binary tree. We present the OOFD algorithm to schedule dissemination of the file iteratively from each peer holding a replica of the file to one of its descendants on the binary tree. We show that, in a homogeneous network, OOFD algorithm is optimum in the sense that time it takes to disseminate the file to all nodes is minimized.