On the tradeoff between playback delay and buffer space in streaming

We consider the following basic question: a source node wishes to stream an ordered sequence of packets to a collection of receivers, which are distributed among a number of clusters. A node may send a packet to another node in its own cluster in one time step, whereas sending a packet to a node in a different cluster takes longer than one time step. Each cluster has two special nodes. We assume that the source and the special nodes in each cluster have a higher capacity and thus can send multiple packets at each step, while all other nodes can both send and receive a packet at each step. We construct two (intra-cluster) data communication schemes, one based on multi-trees (using a collection of interior-disjoint trees) and the other based on hypercubes. We use these approaches to explore the resulting playback delay, buffer space, and communication requirements.