RFC1589 on Kernel Model for Precision Timekeeping

"Joyce K. Reynolds" <jkrey@isi.edu> Thu, 03 March 1994 20:45 UTC

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Subject: RFC1589 on Kernel Model for Precision Timekeeping
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From: "Joyce K. Reynolds" <jkrey@isi.edu>

A new Request for Comments is now available in online RFC libraries.


        RFC 1589:

        Title:      A Kernel Model for Precision Timekeeping
        Author:     D. Mills
        Mailbox:    mills@udel.edu
        Pages:      37
        Characters: 92,260
        Updates/Obsoletes:  none


This memorandum describes an engineering model which implements a
precision time-of-day function for a generic operating system.  The
model is based on the principles of disciplined oscillators and
phase-lock loops (PLL) often found in the engineering literature.  It
has been implemented in the Unix kernel for several workstations,
including those made by Sun Microsystems and Digital Equipment.  The
model changes the way the system clock is adjusted in time and
frequency, as well as provides mechanisms to discipline its frequency
to an external precision timing source.  The model incorporates a
generic system-call interface for use with the Network Time Protocol
(NTP) or similar time synchronization protocol.  The NTP Version 3
daemon xntpd operates with this model to provide synchronization
limited in principle only by the accuracy and stability of the
external timing source.

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does not specify an Internet standard of any kind.  Distribution of
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Joyce K. Reynolds
USC/Information Sciences Institute

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RFC1589 on Kernel Model for Precision Timekeeping Joyce K. Reynolds