Efficient, Reliable and Secure Content Delivery

Delivering content of interest to clients is one of the most important tasks of the Internet

and an everlasting research question of today's networking. Content distribution networks(CDNs)

emerged in response to the rising demand of content providers to deliver contents to clients efficiently,

reliably, and securely at relatively low cost.

This dissertation explores how CDNs can achieve major performance benefits by adopting better

caching strategies without changing the network, or by collaboration with ISPs and taking advantage of their

better knowledge of network status and topology. It discusses the emerging trends of hybrid CDN architectures

and solutions to reliability problems introduced by them. Finally, it demonstrates how CDNs could better

protect both content providers and consumers from attacks and other malicious behaviors.