nanog mailing list archives
Re: Ping triangulation
From: Todd Graham Lewis <lists () reflections mindspring com>
Date: Sun, 28 Jul 1996 00:05:18 -0400 (EDT)
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 - - - - - - - - - - - - - - - - -
Current thread:
- Re: Why aren't ISPs providing stratum 1 NTP service?, (continued)
- Re: Why aren't ISPs providing stratum 1 NTP service? Michael Dillon (Jul 21)
- Re: Why aren't ISPs providing stratum 1 NTP service? Dean Gaudet (Jul 21)
- Re: Why aren't ISPs providing stratum 1 NTP service? Michael Dillon (Jul 21)
- Re: Why aren't ISPs providing stratum 1 NTP service? Dorian R. Kim (Jul 21)
- Re: Why aren't ISPs providing stratum 1 NTP service? Michael Dillon (Jul 22)
- Re: Why aren't ISPs providing stratum 1 NTP service? Christopher E. Stefan (Jul 25)
- Re: Why aren't people changing their subject lines when threads drift? Paul A Vixie (Jul 25)
- Re: Why aren't people changing their subject lines when threads drift? Alan Hannan (Jul 26)
- Ping triangulation Michael Dillon (Jul 26)
- Re: Ping triangulation Roy (Jul 27)
- Re: Ping triangulation Todd Graham Lewis (Jul 27)
- Re: Why aren't people changing their subject lines when threads drift? Michael Shields (Jul 29)
- Re: Why aren't ISPs providing stratum 1 NTP service? Dorian R. Kim (Jul 21)
- Re: Why aren't ISPs providing stratum 1 NTP service? Michael A. Patton (Jul 22)
- Re: Why aren't ISPs providing stratum 1 NTP service? Dean Gaudet (Jul 22)
- Re: Why aren't ISPs providing stratum 1 NTP service? Per Gregers Bilse (Jul 22)
- Message not available
- Re: Why aren't ISPs providing stratum 1 NTP service? Dean Gaudet (Jul 23)