NY ranks #1 in Internet b/w

Alex Rubenstein alex at nac.net
Sun Nov 4 15:19:52 UTC 2001


> Over 300 ms for less than 10000 km (6000 miles) is not great. Even a good
> satellite should be able to provide better round trip times...

That sounds somewhat erroneous. Geosynchronus orbit is about 22,500 miles;
up+down+roundtrip makes that 22,500 * 4, or 90,000 miles;
90,000 / 186,000 miles/sec = 483 milliseconds, which, or course, due to
routers inducing very measureable delay, and the fact that an IP Packet
takes adds a little delay due to its lenght, is usually a bit more.

When working on this stuff (specifically on a hop from Oslo to Jerusalem),
I recall 630 ms being the average latency.

But, to make my point, Geosync orbit could never, ever be less than 483
milliseconds, ever.


-- Alex Rubenstein, AR97, K2AHR, alex at nac.net, latency, Al Reuben --
--    Net Access Corporation, 800-NET-ME-36, http://www.nac.net   --





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