a grid-based infrastructure to support multimedia content distribution
This paper proposes a software architecture able to realise a Content Distribution Network (CDN) , for multimedia data, by means of a Grid computing environment. The key aspect of the proposed approach is exploiting the computational power of a Grid not only to store replicas of the same multimedia content, but also to perform on-the-fly transcoding , when the requesting client is using a player that cannot handle the original file format. The proposed software infrastructure, which exploits Globus Grid services, is able on one hand to identify the storage element , holding the replica, which is the nearest to the client (if such a replica exists); and on the other hand, when the requested file is encoded with a scheme that the player cannot support, the infrastructure selects the computing element which is "best suited" - i.e. has enough computational power - to perform on-the-fly transcoding, thus providing data to the user with the requested format. This selection is based on proper metrics that aim at minimising latencies in order to increase the quality-of-service for the user.
grids content distribution networks quality-of-service multimedia streaming and transcoding