Blossom: Content Distribution Using Inter-Datacenter Networks

Cloud service providers are building out geographically distributed networks of datacenters around the world. It is customary for cloud service providers to distribute their data replicas at multiple geographic locations to mitigate user latency and to increase service availability. In this paper, we treat the content distributed from one datacenter to multiple datacenters as a multicast session. We investigate the problem of maximizing the capacity utilization of inter-datacenter networks while maintaining fairness among multiple multicast sessions. A bandwidth allocation algorithm based on max-min fairness is developed, named Blossom. Blossom leverages a fully polynomial time approximation scheme to accelerate the bandwidth allocation, while achieving an approximation that is (1-ε)-optimal. Through trace-driven simulation, we show that our approach is substantially more efficient than prior work.