Algorithm to estimate download times at various bandwidth rates, in Perl

The end result of this project should be a function written in Perl which could take one or more of the following inputs, and returns an accurate estimate of what the load time would be at 5Mbps, 1.5MBps, and 56k. Possible inputs: * Load time of an entire web page at 10Mbps * Size of the page * Number of image/objects on the page * Load times each image/object * Sizes of each image/object What I don't want is a naive calculation that simply takes the 10Mbps time, and directly extrapolates the other times, as the performance at these other rates is more complex (e.g. different compression rates, parallel downloading of image/objects, round-trip times, etc.). In the end, I just need to feel confident that this huristic is close to reality. If you can run some tests with real hardware and compare to what the huristic returns, all the better.