[Full-Disclosure] Re: Fwd: Re: FullDisclosure: Security aspects of time synchronization infrastructure

[gadgeteer at elegantinnovations.org]

On Fri, Aug 20, 2004 at 10:26:08AM +0400, 3APA3A (3APA3A at SECURITY.NNOV.RU) wrote:
[...]
> you state:
> 
>     If there is a host with reliable time on the network (that is host
>     synchronized with some hardware source, like radio clocks, cesium
>     clocks, GPS clocks, etc) - whole network will be finally, after some
>     time, synchronized with this host.
> 
> Depending upon the criticality of the time sensitive applications on
> the network, you might want to reconsider the use of "radio clocks"
> and especially "GPS clocks".  These time sources are also subject to
> attacks.  Any free air broadcast is subject to jamming.  This is
> essentially a DoS.  Spoofing to provide incorrect time signal is also
> possible with free air broadcast, but less easy to do.
[...]

For a fixed installation detecting if someone is dinking the gps signal
is trivial.  The unit starts thinking it is not in Kansas anymore.
-- 
Chief Gadgeteer
Elegant Innovations