Measurement Study of Netflix, Hulu, and a Tale of Three CDNs

Abstract—Netflix and Hulu are leading OTT (Over-The-Top) content service providers in the US and Canada. Netflix alone accounts for 29.7% of the peak downstream traffic in US in 2011. Understanding the system architectures and performance of Netflix and Hulu can shed light on the design of such large scale video streaming platforms, and help improving the design of future systems. In this paper, we perform extensive measurement study to uncover their architectures and service strategies. Netflix and Hulu bear many similarities. Both Netflix and Hulu video streaming platforms rely heavily on the third-party infrastructures, with Netflix migrating majority of its functions to Amazon cloud, while Hulu hosting its services out of Akamai. Both service providers employ the same set of three CDNs in delivering the video contents. Using active measurement study, we dissect several key aspects of OTT streaming platforms of Netflix and Hulu, e.g., employed streaming protocols, CDN selection strategy, user experience reporting, etc.. We discover that both platforms assign the CDN to a video request without considering the network conditions and optimizing the user perceived video quality. We further conduct the performance measurement studies of the three CDNs employed by Netflix and Hulu. We show that the available bandwidth on all three CDNs vary significantly over the time and over the geographic locations. We propose a measurement-based adaptive CDN selection strategy and a multiple-CDN-based video delivery strategy that can significantly increase users' average available bandwidth.