[43174] in North American Network Operators' Group
Re: Long haul latency calculation?
daemon@ATHENA.MIT.EDU (David Charlap)
Mon Oct 1 16:52:39 2001
Message-ID: <3BB8D755.98DBF76@marconi.com>
Date: Mon, 01 Oct 2001 16:51:33 -0400
From: David Charlap <David.Charlap@marconi.com>
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Christopher Wolff wrote:
>
> I was wondering if there is a benchmark for long-haul circuit
> latency... For example if I had a T1 circuit with 2900 miles
> between the two end-points (and assuming the provider is best case
> scenario) can I do something like (miles*latencyfactor) = 5 ms for
> 2900 miles?
Speed of light is apprxoximately 2.998e+8 m/s (or 299,800,000 m/s),
which is approximately 186,287 miles/sec.
2900 mi / 186,287 mi/s = 0.01557s = 15.57ms. This is the absolute
minimum latency you can possibly get over that distance. Switching
performance and congestion will make your actual latency somewhat
larger.
-- David
