[time-nuts] Type synch

[k6rtm at comcast.net]

Date: Sat, 28 Aug 2010 18:31:14 -0500 
From: "Bill Hawkins" <bill at iaxs.net> 
Subject: [time-nuts] Does GPS time reception work everywhere all of 
the time? 
Bill-- 

Depending on what you mean by "synchronization" you may also want to look at IEEE-1588 (Time Synch) and the work done by John Eidson (at HP/Agilent). 

IEEE-1588 lets you tightly synchronize devices (and data collection) over Ethernet networks. 

(I worked with John at HP/Agilent.) 

Cheers-- 

Bob Martin K6RTM in Silicon Valley 

---------------- 
To: "'Discussion of precise time and frequency measurement'" 
<time-nuts at febo.com> 
Message-ID: <9EF30A464FA04D31B14E6060D19ADEF5 at cyrus> 
Content-Type: text/plain; charset="us-ascii" 

I'm involved with time synchronization of control system 
computers for multi-national businesses. GPS springs to 
mind as a way to synchronize time anywhere. Or is it? 
What about monsoon rains? 

The Internet is available almost everywhere that control 
computers are used, but many users prefer to use a data 
diode between them and the Internet. Control computers 
are now essential for manufacturing processes. Some of 
the processes run constantly for years without stopping 
for any kind of security update. Some of the downtimes 
cost millions of dollars per day. 

A GPS time system allows the control systems to be 
synchronized in time, so that messages sent periodically 
through the data diodes will have the correct time stamp 
on various events that occur in the process. 

But does that work everywhere all of the time? Where can 
I find answers? 

Thanks in advance, as we used to say. 

Bill Hawkins