difference between sntp and ntp server - NTP

This is a discussion on difference between sntp and ntp server - NTP ; Hello, 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. Regards, Pete...

+ Reply to Thread
Results 1 to 5 of 5

Thread: difference between sntp and ntp server

  1. difference between sntp and ntp server

    Hello,

    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.

    Regards,

    Pete

  2. Re: difference between sntp and ntp server

    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.

  3. Re: difference between sntp and ntp server

    Peter Sprenger wrote:
    > Hello,
    >
    > 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.
    >
    > Regards,
    >
    > Pete


    If the SNTP server has a hardware reference clock, there is no
    difference! If the SNTP server is getting time from upstream network
    servers, the differences between NTP and SNTP come into play. The full
    NTP has defenses against the horrible things that happen on a long
    network path and SNTP does not.

    Think "rtime" using the NPT packet format and higher resolution and you
    are close to understanding SNTP.


  4. Re: difference between sntp and ntp server

    Peter Sprenger writes:

    >Hello,


    >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.


    An SNTP server MUST get its time from a local hardware clock only (I
    include radio clocks in that). An NTP
    server can use that, or can use other NTP servers to get its time from.



    >Regards,


    >Pete


  5. Re: difference between sntp and ntp server

    Peter Sprenger wrote:
    > Hello,
    >
    > 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.
    >


    From a client's perspective there is no difference and you should not
    be able to detect a difference. For the actual difference in the server
    and its behavior you should read the NTPv4 draft:
    http://www.ietf.org/internet-drafts/...4-proto-09.txt

    Danny

+ Reply to Thread