We study decentralised low delay degree-constrained overlay multicast tree construction for single source real-time applications. This optimisation problem is NP-hard even if computed centrally. We identify two problems in traditional distributed solutions, namely the greedy problem and delay-cost trade-off. By offering solutions to these problems, we propose a new self-organising distributed tree building protocol called MeshTree. The main idea is to embed the delivery tree in a degree-bounded mesh containing many low cost links. Our simulation results show that MeshTree is comparable to the centralised Compact Tree algorithm, and always outperforms existing distributed solutions in delay optimisation. In addition, it generally yields trees with lower cost and traffic redundancy.
Su-Wei Tan, A. Gill Waters, John S. Crawford