No matter where you go, there they are.

[Perry E. Metzger]

Paul_Koning/US/3Com%3COM at smtp1.isd.3com.com writes:
> Suppose I want to pretend that I am 1000 feet closer to satellite 4 than 
> I really am.  Simple, I take the signals from all the other satellites
> and delay them by 1 microsecond.  That looks like a 1 microsecond
> local timebase error together with a 1 microsecond delay reduction
> to satellite 4.

Aren't things even worse? Since the satelite signals are not
authenticated with anything like public key methods, couldn't I just
synthesize a signal appropriate to any spot on the planet, knowing the
positions of the satelites relative to that spot?

Perry