The demand to access multimedia data such as live video is increasing due to the spread of broadband access network. However, the Internet only provides the so called best-effort service. The network condition of the Internet shows fluctuation. Delivering video without any control causes degradation of the final video quality. To avoid such degradation, we must control video traffic to adapt to the fluctuating available bandwidth. In this paper, we propose a technique to find the available bandwidth for end-to-end stream connections over the Internet. We claim that the correlation coefficient of the network delay of an end-to-end stream is closely related to the bottleneck-link load for the end-to-end stream connection. We show and prove the relationship through analysis and simulations.