ACON: Adaptive construction of the overlay network in CDN-P2P VoD system

P2P VoD deployed on infrastructure of the Content Delivery Network (CDN) is an internet killer application. Each CDN node has an isolated overlay only for a channel's users within the same CDN node, which is different from the traditional pure P2P VoD. However, most channels inside a single CDN node have few concurrent users, so how to construct an efficient delivery overlay to reduce the server load has become a great challenge. In this paper, we study when and how to construct the overlay adaptively and how to control the P2P traffic locality. To this end we propose Adaptive Construction of the Overlay Network (ACON) scheme. According to ACON, each CDN node can find neighbors to construct the overlay from some other specified CDN nodes adaptively and scale the border of the overlay when needed. Experimental results based on extensive simulations have shown the effectiveness of ACON. Compared with isolated overlay construction inside a single CDN node, ACON improves the acceptance rate of users' request about 41% and makes the traffic locality in a controlled way.