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The Quiet Numbers Station: Decoding Nineteen Years of GPS Cryptography

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Re: The Quiet Numbers Station: Decoding Nineteen Years of GPS Cryptography

#31
post #20

Clickbait from 404 Media? Surely not! The part they kept out of the headline: > for use in distributing the keys for accessing the military GPS signals It’s common knowledge that the military has access to a separate, encrypted, higher-precision GPS signal. “Numbers station” implies that they’re distributing unrelated encrypted information, but they’re not; it’s not surprising that GPS signals would be used to delive…

[flagged]

Re: The Quiet Numbers Station: Decoding Nineteen Years of GPS Cryptography

#32
post #7

"Numbers station" is a weird analogy, because the idea of a numbers station was to broadcast messages to undercover operatives in a way that can be received using unmodified (and therefore non-suspicious) household radio receivers. Here, it appears to be a rekeying system for specialized military gear.

“Every receiver in the world decodes Subframe 4, Page 17,” Murdoch said in his new article. [...] “Every GPS satellite is a numbers station,” he concluded.

Re: The Quiet Numbers Station: Decoding Nineteen Years of GPS Cryptography

#33
post #7

"Numbers station" is a weird analogy, because the idea of a numbers station was to broadcast messages to undercover operatives in a way that can be received using unmodified (and therefore non-suspicious) household radio receivers. Here, it appears to be a rekeying system for specialized military gear.

I think it's simply because of using a public channel for encrypted communication.

Yeah GPS is not the people's airwaves it is operated by the US Space Force, I suggest you read up on your history.

Re: The Quiet Numbers Station: Decoding Nineteen Years of GPS Cryptography

#34
post #10

Earlier quoted context omitted.

Yeah its not a number station at all.

I disagree? The point of a numbers station is that it broadcasts in the clear and anyone with a receiver can get it, but only people with the appropriate decryption key can make any use of it. Since it's broadcasting all the time, there's no need for steganography or covert transmission. That's exactly what a numbers station is. Where the article loses me is the implication that this is somehow sinister or beyond the…

> Since it's broadcasting all the time, there's no need for steganography or covert transmission.

Well, you could look at it that way, or you could say that the fact that it's broadcasting all the time is the steganography. That constant transmission of nonsense that nobody wants is what makes it fail to be suspicious when you send a message that somebody does want.

Re: The Quiet Numbers Station: Decoding Nineteen Years of GPS Cryptography

#35
post #10

Earlier quoted context omitted.

Yeah its not a number station at all.

I disagree? The point of a numbers station is that it broadcasts in the clear and anyone with a receiver can get it, but only people with the appropriate decryption key can make any use of it. Since it's broadcasting all the time, there's no need for steganography or covert transmission. That's exactly what a numbers station is. Where the article loses me is the implication that this is somehow sinister or beyond the…

This implication is purely in your head. The article and the scientist whose work it describes are just pointing out the identification of some data that's been transmitted across a public channel for years without anyne noticing.

Re: The Quiet Numbers Station: Decoding Nineteen Years of GPS Cryptography

#36
post #25

Earlier quoted context omitted.

I disagree? The point of a numbers station is that it broadcasts in the clear and anyone with a receiver can get it, but only people with the appropriate decryption key can make any use of it. Since it's broadcasting all the time, there's no need for steganography or covert transmission. That's exactly what a numbers station is. Where the article loses me is the implication that this is somehow sinister or beyond the…

Its all comes down to what we buy as the definition for a number station. For me a number station needs sends a message to be a number station, not a key.

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Re: The Quiet Numbers Station: Decoding Nineteen Years of GPS Cryptography

#37

This is an interesting article. It has a very strong AI accent. I really wish I could tell how real it is. When some part of it I can tell is AI slop, how much of it is AI slop? Inside GNSS has always been a marketing rag with sometimes some interesting articles. The author is a security researcher, so maybe poking at GPS bits makes sense, but talking about floating point bit depth? There's too much slop for me to fi…

So much AI. I stopped immediately. He might have something interesting to say, but apparently not important enough for him to write about it himself, so not important enough for me to read it either.

Re: The Quiet Numbers Station: Decoding Nineteen Years of GPS Cryptography

#38
post #20

Clickbait from 404 Media? Surely not! The part they kept out of the headline: > for use in distributing the keys for accessing the military GPS signals It’s common knowledge that the military has access to a separate, encrypted, higher-precision GPS signal. “Numbers station” implies that they’re distributing unrelated encrypted information, but they’re not; it’s not surprising that GPS signals would be used to delive…

>It’s common knowledge that the military has access to a separate, encrypted, higher-precision GPS signal.

The most militarily-valuable aspect of the military GPS signals is actually the anti-spoofing qualities, rather than the higher precision. Survey-grade GPS gear has been able to achieve centimetre-level precision from the regular civilian signals for several years now, using RF fuckery like tracking the phase angle and other techniques.

To be sure, you want the precision too. NATO countries have M982 Excalibur GPS-guided artillery rounds that are precise enough that you can select not just the building you want to hit but the specific window you want the round to enter.

But the primary benefit of the encrypted signal is that it provides cryptographic assurance that the signal is not spoofed and one can be confident that one's GPS-guided cruise missile or other munition is not being diverted off-course.

Nowadays the military GPS signal has moved from transmitting the legacy "P(Y) code", which is a Cold War-era design, to the "M code" which incorporates several decades' worth of lessons learned in terms of spoofing resistance, cryptographic authentication, etc. It's actually a really neat rabbit hole to climb down.

Re: The Quiet Numbers Station: Decoding Nineteen Years of GPS Cryptography

#39
post #20

Clickbait from 404 Media? Surely not! The part they kept out of the headline: > for use in distributing the keys for accessing the military GPS signals It’s common knowledge that the military has access to a separate, encrypted, higher-precision GPS signal. “Numbers station” implies that they’re distributing unrelated encrypted information, but they’re not; it’s not surprising that GPS signals would be used to delive…

I don't think this qualifies as clickbait in the sense that the headline mismatches the contents. My experience with 404 Media is that they treat every article like they've just released the Pentagon Papers, so you just have to read with that in mind.
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