3 ms·
Very interesting. I wonder if it's possible to detect and protect against a spoofed GPS signal by cross-referencing with trusted/canonical online data (eg. NTP
by mseebach 11y ago
Very interesting.
I wonder if it's possible to detect and protect against a spoofed GPS signal by cross-referencing with trusted/canonical online data (eg. NTP and almanac data from NASA)?
- Johnnybe 11y agoYes.
- michaelt 11y agoOnly against imperfect spoofing. A GPS receiver in Los Angeles sees the same set of signals as a receiver in San Francisco - just the relative arrival times of the signals are different by, at most, a single-digit number of milliseconds. So an attacker just needs to do a replay attack, and all the almanac stuff checks out fine because it's a perfect replica of the authentic signal.
- coin 11y agoMost phones also have a GLONASS receiver, which is Russia's GNSS.