[ntp:questions] Re: SNTP Client/Server questions
stenn at ntp.isc.org
Tue Aug 15 22:50:18 UTC 2006
>>> In article <1155648559.784059.118920 at 75g2000cwc.googlegroups.com>, david.lindauer at honeywell.com writes:
david> I've got a question about the rationale behind the SNTP RFC2030.
david> Basically, a valid SNTP server is supposed to be sourced directly
david> from a reference, never from a remote NTP server. We believe this is
david> because of the lack of sophisticated algorithms as found in NTP; e.g.
david> sourcing an SNTP server from an NTP server is going to be inherently
david> less accurate. Is that the gist of it, or is there other rationale
david> as well?
Yes, to the best of my knowledge.
david> Also, assuming an SNTP client is doing similar to the spec and
david> aliasing the server time with a calculated propagation delay, and
david> assuming a LAN rather than the internet at large, can anyone give a
david> general feel for how far off the client is going to be from its
It depends on how good the system clock is and how often sntp polls.
david> Finally, are those equations for round trip time and propagation
david> delay in RFC2030 actually correct? They aren't what I would expect,
david> and don't even seem to match each other.
Please see the updated/newer RFC:
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