[LEAPSECS] google abandons NTP ?

[Steve Allen]

On Mon 2012-11-26T18:30:09 +0000, Poul-Henning Kamp hath writ:

> Uhm, they run PTP, so what ?


That doesn't quite seem to be the case.  The paper is at
http://static.googleusercontent.com/external_content/untrusted_dlcp/research.google.com/en//archive/spanner-osdi2012.pdf

In that is

    The underlying time references used by TrueTime are GPS and atomic
    clocks.  TrueTime uses two forms of time reference because they
    have different failure modes.  GPS reference-source
    vulnerabilities include antenna and receiver failures, local radio
    interference, correlated failures (e.g., design faults such as
    incorrect leapsecond handling and spoofing), and GPS system
    outages.  Atomic clocks can fail in ways uncorrelated to GPS and
    each other, and over long periods of time can drift significantly
    due to frequency error.

It seems to indicate that the "leap smear" is one of the features
implemented within this scheme.

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