[Info-vax] SYS$TIMEZONE.DAT

[lists at openmailbox.org]

On Mon, 16 Mar 2015 19:00:26 -0400
David Froble via Info-vax <info-vax at rbnsn.com> wrote:

> lists at openmailbox.org wrote:
> > On Sun, 15 Mar 2015 13:37:21 -0400
> > David Froble via Info-vax <info-vax at rbnsn.com> wrote:
> > 
> >> Yes, but maybe the pertinent question is, "how many users need
> >> accurate time?"
> > 
> > VMS clustering can work without accurate time across the cluster?
> > 
> >> If not at all, then any changes is an imposition for no gain.  If
> >> "it's nice, but not critical", pretty much the same.
> >>
> >> Not too many things in this world are perfect, maybe none at all.
> > 
> > Time is something most clustering and most interconnected computers
> > need to agree on.
> > 
> 
> Agree on, I'll give you.  But accurate, what does that matter?

It depends. If the only interaction is within cluster members that appears
to have already been answered by those who know. But even there stuff like
Kerberos if it is supported on VMS is supposed to break if the times get
too far out of whack. I'm not sure how far it has to get but I think it's a
matter of seconds rather than minutes.

Many times (no pun intended) you have to synchronize for example with online
transactions across global networks. Think about a credit card or POS
network (yeah, I know) or ATM network. Everybody has to have the same time
in order to protect against cryptographic replay attacks. And if you need to
reconcile financials across a major network you also need everybody to
agree on time. There are also regulatory issues about this as usual.
Assuming the parties don't get time from each other but get it
independently for security reasons it would suggest accurate time is also
important otherwise they could never agree.

-- 
Please DO NOT COPY ME on mailing list replies. I read the mailing list.
RSA 4096 fingerprint 7940 3F02 16D3 AFEE F2F8  ACAA 557C 4B36 98E4 4D49