[ntp:hackers] NTP Stratum FYI - L1 GPS sucks as a source of trusted time & you probably wont like this commentary!

todd glassey tglassey at earthlink.net
Tue Mar 1 14:41:22 UTC 2011

On 2/28/2011 11:11 PM, Terje Mathisen wrote:
> todd glassey wrote:
>>> BTW, Todd, I would be really happy if this was the last time I had to
>>> read another of your complaints about insufficient authentication for
>>> timestamps. :-(
>>> Terje
>> Why because you are offended anyone would ask you to prove anything?
> No, but because the actual threat model is much, _much_ simpler:
> Somebody with the resources to attack you by forging bad GPS-NTP 
> timestamps has the resources to develop a new Stuxnet worm as well, 
> i.e. they can attack your internal infrastructure directly instead of 
> having to go for a limited number of external time sources.
> In this case it is _far_ simpler to attack the relevant servers 
> directly and hack the local clocks than it is to attack a majority of 
> the configured time sources for a competent NTP setup.
> There is never such a thing as a 100% authenticated anything, what you 
> can get is simply levels of trust, and most of the time you can get 
> the quality far above what's needed to convince a judge/jury.
> Terje
So we disagree on just about everything here. Lets leave it at that.


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