Re: Origin Servers without Clocks
nemo/Joel N. Weber II (devnull@gnu.ai.mit.edu)
Tue, 22 Apr 1997 18:55:40 -0400
Date: Tue, 22 Apr 97 18:17:14 EDT
From: "Ross Patterson" <Ross_Patterson@ns.reston.vmd.sterling.com>
While I understand and sympathize with the issue here (I've already
got too many clocks in my home, I don't need more to reset twice a
year!), I find it suprising that TCP can be implemented on a system that
has no timing facilities. For that matter, don't many (most?) embedded
systems have a real-time kernel, with a timer-based dispatcher? Or am I
mistaking a timer for a time-of-day-and-date clock?
Yes, there's a difference between a timer designed to help with mutlitasking
and a timer which tells you the time of day.
Assuming a completely standalone server which has no battery backup,
which boots using DHCP and tftp or whatever (or has all its software
in ROM--though then it still needs at least rarp), there's generally
no need to have a clock to run a soda machine or a thermometer.
Admittedly, a soda machine which logs times people get sodas
is quite interesting. So is a thermomenter which generates
nice graphs showing time.
Admittedly, if you're going to all this trouble, you could ask
another machine on the network for the time; but I bet there are
other applications where you don't care about the time.
(What about routers? Some of them can be configured from the web;
but why would a router care about wall clock time?)