Open Connect Everywhere: A Glimpse at the Internet Ecosystem through the   Lens of the Netflix CDN
  The importance of IXPs to interconnect different networks and exchange traffic locally has been well studied over the last few years. However, far less is known about the role IXPs play as a platform to enable large-scale content delivery and to reach a world-wide customer base. In this paper, we study the infrastructure deployment of a content hypergiant, Netflix, and show that the combined worldwide IXP substrate is the major corner stone of its Content Delivery Network. To meet its worldwide demand for high-quality video delivery, Netflix has built a dedicated CDN. Its scale allows us to study a major part of the Internet ecosystem, by observing how Netflix takes advantage of the combined capabilities of IXPs and ISPs present in different regions. We find wide disparities in the regional Netflix deployment and traffic levels at IXPs and ISPs across various local ecosystems. This highlights the complexity of large-scale content delivery as well as differences in the capabilities of IXPs in specific regions. On a global scale we find that the footprint provided by IXPs allows Netflix to deliver most of its traffic directly from them. This highlights the additional role that IXPs play in the Internet ecosystem, not just in terms of interconnection, but also allowing players such as Netflix to deliver significant amounts of traffic. 
Timm B\"ottger, Felix Cuadrado, Gareth Tyson, Ignacio Castro, Steve   Uhlig
cs.NI