A Simple Approach of Improving DNS based CDN Video Sharing System

Video sharing is becoming a popular service in Internet. As the popularity of video sharing goes up, the cost of operating a video sharing system is also soaring upward. With its good scalability and flexibility, CDN is commonly adopted as the basic platform in most video sharing services. In this paper, we introduce a typical DNS based CDN architecture, and focus on improving the performance for single surrogate servers with "cache-tracker" scheme, which is a request-routing strategy based on the status of hard disk IO and the status of content caching in all surrogate servers\´ physical memory. We use some detailed simulations to evaluate "cache-tracker" and compare it to some other commonly-used request-routing strategies. These simulations clearly demonstrate the effectiveness of our simple approach.