[ntp:questions] difference between sntp and ntp server

David Woolley david at ex.djwhome.demon.co.uk.invalid
Mon Mar 31 10:05:05 UTC 2008

Peter Sprenger wrote:
> a simple question: Is there a difference between a ntp server and a sntp 
> server? I studied the RFC's, but found no evidence, that for the server 
> side there are differences.

NTP servers are always (give or take version and permission 
considerations) acceptable to SNTP clients.

An SNTP server behaves the same as a stratum 1, NTP server, supporting 
only client/server and broadcast modes.  It must only be used where an 
NTP server would be stratum 1 (i.e. early (pre-Windows 2003) versions of 
w32time cannot legally act as servers).

Earlier version of the SNTP spec permitted more association modes. 
Earlier versions didn't allowed impending leap seconds to be signalled.

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