[LEAPSECS] presentations from AAS Future of Time sessions

[Ian Batten]

On 16 Jan 2014, at 15:03, Warner Losh <imp at bsdimp.com> wrote:

> 

> I think the answer for 1970-1990 is that most of them were aligned to local time (even if the system ticked in virtual UTC/GMT time) with sub-minute accuracy. Time alignment started to matter as more computers were networked together to work cooperatively on problems. Starting in the mid 1980's with things like the VAXcluster, which had its own time alignment protocol, you see more attention paid to this problem. ntp and similar protocol adaptation during the late 80's was driven by the rollout of NFS servers and Unix workstations.


That was certainly my experience as an administrator, rather than as a developer: we had a distributed build environment based around
a load of multi-processor Suns and an Auspex, and a whole bunch of nasty problems went away when we started running NTP.  As I
happened to have radio clocks (Truetime MSF receiver) to hand because the products we were building, I "borrowed" one of them to
get the machines aligned to a reference clock rather than an arbitrary clock.  But the problems would have been solved just by distributing
the Auspex's clock; that we had UTC rather than crufty-time was a luxury.  At the time we either didn't have an Internet connection, or if we did
it would have been 9600 baud X25 and not really usable for anything like NTP.

ian