3 ms·
Why would you need to have keys at all? Just rebroadcast the signal with a different delay for each satellite.
by 7952 15y ago
Why would you need to have keys at all? Just rebroadcast the signal with a different delay for each satellite.
- pferreir 15y agoI guess there should be some kind of timestamp preventing that kind of attack, no?
- deleted 15y ago[deleted]
- sern 15y agoThe GPS military signal is protected by virtue of being CDMA-modulated by a long, pseudorandom sequence (the output of a keyed, secret PRNG). Because of the spread-spectrum nature of CDMA, it would be impractical to record the signal without having the key in the first place. And if you did have the key, why go through the trouble of recording and replaying the signal when you could directly spoof it?