Depends on your definition of a "clock." I don't think over time that all
devices will have a chip or a section of a chip dedicated to time. Rather,
basic software counters can be used to measure elapsed time from a known
starting point and periodically re-synch to a network time source.
BTW: I expect your VCR changed to PDT automatically on the right date, not
because of the PBS source but because of the same reason your PC changed to
PDT... it was the right Sunday morning to do so.
Don
Robert.Herriot%pahv.xerox.com at interlock.lexmark.com on 05/12/99 07:27:37 PM
To: Don Wright at LEXMARK, cmanros%cp10.es.xerox.com at interlock.lexmark.com
cc: ipp%pwg.org at interlock.lexmark.com
Subject: RE: IPP> MOD - part of Issue 17 - don't neednegative"time-at-xxx" Job
Attributes
I would offer an alternate view to Don's. I expect that most internet
devices will have a clock which will set itself and update itself from an
internet time service. I would not expect most devices to have no clock and
to get their time exclusively from the internet because of the inherent
unreliability of the network (a Jini assumption too).
VCRs manufactured today use a similar mechanism. The have clock which sets
itself from the time signal broadcast by the local PBS station, and they
seem to update their clock from this signal as well. My VCR changed to PDT
on its own. I assume that it was from the time signal.
Bob Herriot
-----Original Message-----
From: don at lexmark.com [mailto:don at lexmark.com]
Sent: Thursday, April 29, 1999 12:45 PM
To: cmanros at cp10.es.xerox.com
Cc: ipp at pwg.org
Subject: RE: IPP> MOD - part of Issue 17 - don't
neednegative"time-at-xxx" Job Attributes
Carl-Uno Manros said:
"My personal conviction is that ALL Internet attached devices will need to
have
a way to indicate time in the foreseeable future."
Well, I certainly and completely disagree that this means every device has a
clock. What a complete waste of money, time and effort for millions of
devices
interconnected to a global or perhaps universal network all carrying around
their own little time piece, no two of which agree. A central source of
date
and time correct and compensated for networking delays, etc. is clearly the
correct solution to this problem.
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* Lexmark International *
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