Abstract
Today, a large fraction of Internet traffic is originated by Content
Providers (CPs) such as content distribution networks and hyper-giants. To cope
with the increasing demand for content, CPs deploy massively distributed
infrastructures. This poses new challenges for CPs as they have to dynamically
map end-users to appropriate servers, without being fully aware of network
conditions within an ISP as well as the end-users network locations.
Furthermore, ISPs struggle to cope with rapid traffic shifts caused by the
dynamic server selection process of CPs.
In this paper, we argue that the challenges that CPs and ISPs face separately
today can be turned into an opportunity. We show how they can jointly take
advantage of the deployed distributed infrastructures to improve their
operation and end-user performance. We propose Content-aware Traffic
Engineering (CaTE), which dynamically adapts the traffic demand for content
hosted on CPs by utilizing ISP network information and end-user location during
the server selection process. As a result, CPs enhance their end-user to server
mapping and improve end-user experience, thanks to the ability of
network-informed server selection to circumvent network bottlenecks. In
addition, ISPs gain the ability to partially influence the traffic demands in
their networks. Our results with operational data show improvements in path
length and delay between end-user and the assigned CP server, network wide
traffic reduction of up to 15%, and a decrease in ISP link utilization of up to
40% when applying CaTE to traffic delivered by a small number of major CPs.