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SANS ISC: Change your clocks? - SANS Internet Storm Center SANS ISC InfoSec Forums

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Change your clocks?

For those of us living in many parts of the world today is the day to change your clock back one hour on those devices that don't do so automatically. In fact, since DST changed in some countries those devices that do change themselves now do so on the wrong day, requiring two manual changes. Case in point, our household alarm clock.  Also our daughter wakes at precisely 6am and does not adjust to changes in timezone or DST very quickly.  Find any devices or systems that should change, but didn't? Things that change on the original dates, now that DST is on different days now? Let us know in comments below, or via our contact form here

Adrien de Beaupré Inc.

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Adrien de Beaupre

353 Posts
ISC Handler
Jan 24th 2011
Welcome to corner cutting and failure of imagination in programmers. The short cut is changing the time per a date table algorithm. The failure of imagination is not taking into account that these arbitrary dates could change in the future. Why the above statements?

The NIST time code transmits date, time and dst information. The DST flags take into account upcoming change, changeover and post time change. The European standard does the same thing. There's no excuse for this, in fact I created a WWV clock that actually uses DST flags to properly decode the current time and date. And did it because I own one of these clunker Atomic Clocks. Oregon Scientific, seems to do it right the others can be variable junk.
Don't forget your home energy management system (the automatic thermostat) which sets your inside temperature to different levels throughout the day and night. Most have no clue what DST is, so you have to manually adjust those too. Ditto for those mechanical timers that turn on/off security lights or perhaps the light in the fish tank.

301 Posts
ISC Handler
<rant>Congress should just keep their d*mn hands off our clocks. If they want to get up an hour earlier, they can set their alarms an hour earlier. With recent expansions in the DST period, we're approaching the situation of *always* being in DST, which means all year long (currently most of the year long) we'll be getting to work at 7 and pretending it's 8 so we can get off at 4 instead of 5, instead of just deciding to start work at... 7! When DST is 12-months long, does that mean that we have redefined the officially meaning of noon to be the hour *before* the sun transits the meridian? X-P </rant>

50 Posts
My Android 2.1 (unrooted, stock Verizon) LG Ally went back 1 hour on Sunday, November 1st. I noticed it at 10:30am that day and then I powered down my phone, booted it back up and it successfully went from the incorrect 9:30am to the correct 10:30am.

Then on the real DST day 11/7 it correctly adjusted itself. No problems.

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