Gaussian approximation of CDN call level traffic.

The Content Distribution Networks (CDN) are based on one of the most fruitful ideas in nowadays Internet. There is an increasing competition between CDN providers that place their Web servers in various locations, closer to end users. The future Internet solutions have to assure however that users are not only able to observe the live events and download different content via caching systems, but also that the CDN providers can ensure the quality adequate to the observed demand. This requires knowledge about the characteristics of traffic incoming to the system. In this paper we analyzed the call-level CDN traffic on the base of observations and measurements taken from the Polish Telecom CDN network.