In a message written on Thu, Jul 16, 2009 at 02:07:12AM -0400, Sean Donelan wrote:
Unless you were Federal Express, and wanted to understand where the "center" of your service area was to help pick better airport hub locations. Add in some offsets for time zones, weather, and even more complexity and your hub ends up in Memphis. Optimal can sometimes mean its good enough, even the momument at the center of the United States isn't actually located at the precise center.
The center of FedEx's world has nothing to do with geography, it has to do with flight times. JFK's prennial 1 hour delays make that flight an hour longer, even though it is no further away. Also, if I had 20 flights to the east coast, and 1 flight to the west coast, I may well "shift my center" east choosing to burn more fuel and time on one flight to save fuel on 20. Oh yeah, and then there are the other hubs in Indianapolis, Fort Worth, Oakland, Newark, Anchorage, Paris, Guangzhou, Toronto and Miami. Guess Memphis isn't the best, all by itself. Anchorage you might say? That's odd. Well, turns out a fully loaded freight aircraft have trouble making it from many Asian countries to the US on one tank of fuel. If you have to stop to refuel you might as well sort some packages while your waiting for it to pump into the plane.
Operations research is filled with people trying to figure out the optimal number of hubs, hub locations, routes between them for all sorts of stuff.
So where are the operations research people studying the Internet?
At every ISP and content provider out there. The answer is different for every company. FedEx and UPS don't have the same hubs, because they don't serve the same customer base. Akamai, NTT, and DTAG all have different points of presense based on their customer bases. Each one has the "optimal" network for their customer base. Your question is akin to tell me the best car, house, boat, airline, ISP, operating system. Magazines love to crown the king, but we all know making the right choice has orders of magnitude more to do with your specific situation than it does with the product or service in the abstract. -- Leo Bicknell - bicknell@ufp.org - CCIE 3440 PGP keys at http://www.ufp.org/~bicknell/