This and other important results are found in this most interesting paper by Mark E. Crovella and Robert L. Carter , which I found almost by chance with Alta Vista . Thus, the distance in hops between two hosts is not necessarily a good predictor of the expected latency of a document transfer. The extra cost at runtime incurred by dynamic latency measurement, as compared to prior static knowledge of hop distances, is well justified based on the resulting improved performance. Selection based on dynamic latency measurement is preferable to random selection. As an added bonus, you gain fault tolerance.
Network congestion plays a significant role in the overall distribution of round trip times.
In fact, even random server selection is preferable to choosing any static server for documents larger than 5K bytes. If there is demand, I will build a 68000 version for separate distribution. QuickestMirror measures Accurate Round Trip Time as described by Sustainable Softworks . It might thus be a good idea to be able to set preferences for the order in which the alternative hosts are to be contacted, otherwise the first four listed alternatives might be over the Atlantic, but there were European alternates that were stopped by the proxy. As a matter of fact, IE kicks QM to the foreground, whereas Netscape leaves QM in the background.