Peer-assisted content distribution in Akamai netsession

Content distribution systems have traditionally adopted one of two architectures: infrastructure-based content delivery networks (CDNs), in which clients download content from dedicated, centrally managed servers, and peer-to-peer CDNs, in which clients download content from each other. The advantages and disadvantages of each architecture have been studied in great detail. Recently, hybrid, or 'peer-assisted', CDNs have emerged, which combine elements from both architectures. The properties of such systems, however, are not as well understood.