Cooperative Content Distribution and Traffic Engineering in an ISP Network

Abstract:

Traditionally, Internet Service Providers (ISPs) make profit by providing Internet connectivity, while content providers (CPs) play the more lucrative role of delivering content to users. As network connectivity is increasingly a commodity, ISPs have a strong incentive to offer content to their subscribers by deploying their own content distribution infrastructure. Providing content services in a provider network presents new opportunities for coordination between \emph{traffic engineering} (to select efficient routes for the traffic) and \emph{server selection} (to match servers with subscribers). In this work, we develop a mathematical framework that considers three models with an increasing amount of cooperation between the ISP and the CP. We both analytically and numerically study the stability and optimality conditions for these models. We show that separating server selection and traffic engineering leads to sub-optimal equilibria, even when the CP is given accurate and timely information about the ISP's network in a partial cooperation.
More surprisingly, extra visibility results in a {\em less} efficient outcome and such performance degradation can be unbounded.
Leveraging ideas from cooperative game theory, we propose an architecture based on the concept of \emph{Nash bargaining solution} that significantly improves the fairness and efficiency of the joint system. Simulations on realistic backbone topologies are performed to quantify the performance differences between our models. We show that the joint design significantly improves the performance metrics of both the ISP and the CP, under a wide range of traffic conditions. This study is a step toward a systematic understanding of the interactions between those who provide and operate networks and those who generate and distribute content.