Superchunk-Based Efficient Search in P2P-VoD System

In this paper, we seek to provide reliable and fast content discovery in peer-to-peer (P2P) video-on-demand (VoD) system to enable user interactivity under peer dynamics. We first identify two characteristics of content discovery in P2P-VoD: real-time constraints and limited local cache. Tapping on these properties, we propose a hybrid content discovery mechanism: SUpeRchunk- based eFficient search Network (SURFNet). SURFNet divides movies into superchunks and chunks. Stable peers that are likely to have longer lifespans in the system are used to construct an AVL tree to provide superchunk-level data availability information. Peers storing the same superchunk are grouped into a holder-chain, which is then attached to a node in the AVL tree. This structured overlay is further extended by a gossip-based unstructured network for chunk-level information exchange and data transmission. Since the AVL tree consists of only stable peers, it provides a reliable backbone even in highly dynamic environment. Our analysis and simulation results show that SURFNet supports nearly-constant and logarithmic search time for seeking within a video and jumping to a different video, respectively.