Effective epidemic dissemination of multimedia metadata in Peer-to-Peer overlay networks: The Metis architecture and prototype

There is a clear and widely recognized trend toward a growing and unprecedentedly large amount of user-generated content, which users are willing to share in an easy, cheap, and immediate way. This poses novel hard technical challenges for Peer-to-Peer (P2P) content distribution. We claim that a crucial technical factor to spread even more P2P distribution of multimedia content, is the availability of effective solutions to make rich metadata promptly accessible to users. However, state-of-the-art research and industrial practices are still too weakly addressing the problem and, to the best of our knowledge, none of the existing solutions offers an adequate support for metadata distribution in P2P networks. This paper presents the design and implementation of a prototype (called Metis and available for download) for metadata dissemination in P2P overlay networks. Metis proposes several original contributions: it is fully decentralized; it exploits a set of dynamically selectable/configurable epidemic dissemination protocols; it can be easily integrated on top of existing P2P overlays, such as Tribler. The reported experimental results show the feasibility of our approach, which achieves good dissemination coverage and promptness with very limited overhead.