[43162] in North American Network Operators' Group
RE: Long haul latency calculation?
daemon@ATHENA.MIT.EDU (Bruce Morgan)
Sun Sep 30 22:38:00 2001
From: "Bruce Morgan" <bruce.morgan@aarnet.edu.au>
To: <chris@bblabs.com>, <nanog@merit.edu>
Date: Mon, 1 Oct 2001 12:38:25 +1000
Message-ID: <NEBBLCKHALNGEKCODEHGAEHBCCAA.bruce.morgan@aarnet.edu.au>
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Hi Chris,
On long haul and reasonable bandwidth, I figure as a rough estimate to
divide the distance in kilometers by 100 will be a very close approximation
to an RTT in ms. For instance I get 147 ms ICMP RTT on the Southern Cross
Sydney-Seattle link where the fibre path is about 14700 km. It assumes a
transmission speed close to .66 the speed of light. The calculation using
miles is a little messier ;-)
Bruce
> -----Original Message-----
> From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of
> Christopher Wolff
> Sent: Monday, 1 October 2001 12:09 PM
> To: nanog@merit.edu
> Subject: Long haul latency calculation?
>
>
>
> Dear Nanog:
>
> 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?
>
> Thanks,
> Christopher
>
