Collaborative ISP-CP live streaming

When a content provider (CP) provides peer-topeer live streaming service, routing decisions with the knowledge of underlay traffic can often lead to much better performance (such as user delay). On the other hand, if the Internet Service Providers (ISPs) provide underlay traffic information to the CP, their overall network cost due to routing inefficiencies can be reduced. There is hence incentive for ISP-CP collaboration. In this paper, we study protocol design to reduce network cost for such collaboration. We consider two ways of collaboration: one on complete information sharing (i.e., the case of ISPs playing the role of CP), and the other one on limited information sharing by means of peer ranking (i.e., the case of P4P framework through Oracle/iTracker). We first formulate the problem of minimizing network cost with a certain delay target, and show that it is NP-hard. For complete information sharing, we propose a centralized heuristic which achieves low network cost. For limited information sharing, we present a simple distributed algorithm called Coppice (Collaborative ISP-CP live streaming service) which achieves low network cost. Simulation results show that indeed there is a strong benefit for ISP-CP collaboration, and substantial performance can be gained if ISPs can share complete network information with CP.