ZTE Corporation ZTE Corporation ZTE Corporation ZTE Corporation This document defines a P2P CDN (Content Delivery Network) based content sharing system using PPSP (Peer to Peer Streaming Protocol) and RELOAD (REsource LOcation And Discovery). The P2P CDN provides a unified platform for service/content providers and content sharing users to share content efficiently and safely. The shared contents may include streaming media, files, etc. This content sharing system uses PPSP as signaling protocol for P2P content distributing, and uses RELOAD to improve reliability and scalability. More specifically, RELOAD is used to construct P2P overlays storing of massive contents and locating contents reliably.