NTP question

Mel Beckman mel at beckman.org
Thu May 2 03:56:05 UTC 2019


Gary, Gary, Gary,

You don’t need a $30,000 GPS simulator to verify if a GPS product in your inventory has the rollover bug. You simply ask the supplier to certify that they don’t have the rollover bug. They use their _$100,000_ GPS simulator If needed, but usually it’s done with a trivial code review. 

If the supplier can’t provide such a certification, then they are no longer a supplier. This tends to persuade them to certify. 

If you as an air carrier (or any other critical GPS consumer) fail to ask for such a certification in time to field a replacement, that’s your fault.

You might not be aware, but zero US air carriers had any unplanned  downtime from the GPS rollover. I can’t say the same thing for certain Asian air carriers :)

-mel via cell

> On May 1, 2019, at 8:39 PM, Gary E. Miller <gem at rellim.com> wrote:
> 
> Yo Mel!
> 
> On Thu, 2 May 2019 03:30:03 +0000
> Mel Beckman <mel at beckman.org> wrote:
> 
>> I’m also an FAA licensed A&P mechanic, and have worked for airlines
>> in fleet maintenance.  Air carriers have extremely thorough systems
>> reviews, by law, through the Airworthiness Directive program, which
>> started identifying 2019 GPS rollover vulnerabilities in ... 2009!
>> Nobody was surprised.  If any GPS systems “went nuts”, it was through
>> the incompetence and negligence of their owners.
> 
> How many GPS owners happen to have $30,000 GPS simulators to check
> their $300 GPS/NTP servers?  Some of mine did, most did not.
> 
> Seems to me the negligence is in the GPS manufacturer that failed to
> notify their customers.
> 
> To be fair, Avidyne and Telit did notify their customers, but not with
> a fix or enough lead time to swap out the units.
> 
> RGDS
> GARY
> ---------------------------------------------------------------------------
> Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
>    gem at rellim.com  Tel:+1 541 382 8588
> 
>        Veritas liberabit vos. -- Quid est veritas?
>    "If you can’t measure it, you can’t improve it." - Lord Kelvin


More information about the NANOG mailing list