I think the answer you will find is that standard GPS is fairly easy
to jam. The satellite transmissions are fairly weak, which means that
a strong ground-based transmitter on the same set of frequencies could
effectively jam GPS reception. Indeed, the US military has stated
that they can jam GPS in a region if necessary.
As for corrupting the signal, I think that would require a bit more
work, but I personally think it could be done. I don't think there is
any kind of cryptographic integrity protection of GPS signals.
However, I would love to be proved wrong.
-derek
[EMAIL PROTECTED] writes:
> Thanks to Eugene and Ian... but... I'm afraid Dorothy's note is just a
> brief discussion of the potential applications of SmartLocator.
> SmartLocator is/was a product/prototype of International Series Research
> Inc., around 1996; I haven't found any more info about it (further to
> Denning's note) and suspect it doesn't exist anymore. In any case, based on
> what I've read in Denning's article, I think SmartLocator does not claim to
> secure GPS integrity. SmartLocator claims to provide a `location signature`
> using GPS, that is, a way to prove that the sender of a message has a GPS
> receiver in a particular position in space and time. Actually, this could
> indeed be quite useful, if this works, so one wonders how it worked and why
> one (me) never heard of it so far. Maybe someone on the list knows better?
> Or maybe we should look for a patent. Frankly: my expectations are low, I
> will be surprised if this was really done securely.
>
> Best Regards,
> Amir Herzberg
>
> IBM Research Lab in Haifa (Tel Aviv Office)
> http://www.hrl.il.ibm.com
>
>
> Eugene Leitl <[EMAIL PROTECTED]> on 05/09/2000 12:10:27 AM
>
> Please respond to Eugene Leitl <[EMAIL PROTECTED]>
>
> To: Ian BROWN <[EMAIL PROTECTED]>
> cc: [EMAIL PROTECTED], [EMAIL PROTECTED]
> (bcc: Amir Herzberg/Haifa/IBM)
> Subject: Re: GPS integrity
>
>
>
>
>
> I presume the paper in question is
> http://www.cs.georgetown.edu/~denning/infosec/Grounding.txt
>
> Ian BROWN writes:
> > Dorothy Denning wrote an interesting paper on authenticating location
> using
> > GPS signals... I think it's reachable from her home page as well as the
> > following citation:
> >
> > D. E. Denning and P. F. MacDoran, "Location-Based Authentication:
> Grounding
> > Cyberspace for Better Security," Computer Fraud and Security, Feb. 1996
> >
> > Ian :)
> >
>
>
>
>
>
--
Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
Member, MIT Student Information Processing Board (SIPB)
URL: http://web.mit.edu/warlord/ PP-ASEL N1NWH
[EMAIL PROTECTED] PGP key available