Content delivery and caching from a network provider's perspective

An ongoing challenge in telecommunication is to integrate a variety of services on broadband access platforms at increasing transmission speed. Traditional Internet services, such as file transfer, email and web browsing, are now running on common multi-service IP platforms together with voice, video and television over IP, online gaming, P2P downloads, etc. While broadband access is becoming established as standard for homes and via mobile devices, the networking capacities in the access and the backbone are steadily being extended to keep pace with higher traffic volumes. Content delivery (CDN) and peer-to-peer (P2P) networks carry most of today's Internet traffic with different effects on delay and throughput as the main quality-of-service characteristics. We give an overview of the current techniques for distributing content over the Internet via server-based and peer-to-peer overlays regarding their impact on the traffic profiles. We consider link-level measurement on network provider platforms as a basis for network-wide traffic engineering, including load balancing and for current trends and prognosis. Many recent activities in research, industry and standardization have addressed the localized delivery of large content volumes from the network edge and via exchange between peers. The main goal, namely to shorten end-to-end paths and delays, would not only enhance the user experience and benefit network providers by reducing the load in the backbone and on expensive global interconnection links, but would also, last but not least, reduce energy consumption. (C) 2011 Elsevier B.V. All rights reserved.