On hierarchical collaborative content distribution over communication networks

Content distribution applications such as video streaming, file sharing, and network gaming are posing strict requirements on the development and enhancement of communications technologies, architectures, and protocols. Collaboration is one of the central techniques for designing enhanced communication networks. In this work, we address the problem of collaborative content distribution where destination nodes collaborate by sharing, over peer-to-peer connections or mobile-to-mobile links, data blocks received from a source node. We calculate the total number of possible distribution trees as a function of the number of data blocks and destination nodes for a two-level hierarchy, and generalize results to a multilevel hierarchy. Moreover, we develop a content distribution cost model and discuss special case content distribution scenarios.