[3620] in North American Network Operators' Group
Re: Ping triangulation
daemon@ATHENA.MIT.EDU (Todd Graham Lewis)
Sun Jul 28 00:11:00 1996
Date: Sun, 28 Jul 1996 00:05:18 -0400 (EDT)
From: Todd Graham Lewis <lists@reflections.mindspring.com>
To: Roy <garlic@garlic.com>
cc: Michael Dillon <michael@memra.com>, nanog@merit.edu
In-Reply-To: <31FABBF3.617A@garlic.com>
On Sat, 27 Jul 1996, Roy wrote:
> They use the ping times to figure out which server would be closest.
> All the servers are not located in the same place. The idea is that
> european users may receive better service from a european server.
This brings to mind a question: are ping times a more appropriate vector
than hopcount or topological locality? Ping times reflect a lot of
important (but ephemeral) aspects of performance which more direct
measurements do not. E.g., the latency of trans-pond links nicely
reflects their cost in a matter not easily captured in simple topology
maps. Ditto for congested links which might be closer to the viewer.
Of course cacheing solves all of these problems (J <- hook next to bait),
but in this imperfect of worlds, what reasons, if any, make ping time
less attractive than other metrics? I used to think them simple-minded
and sloppy, but now I am not so sure.
_____________________________________________________________________
Todd Graham Lewis Linux! Core Engineering
Mindspring Enterprises tlewis@mindspring.com (800) 719 4664, x2804
