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Number Stations and Enigma Stations

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Re: Number Stations and Enigma Stations

#11

Post by gorgoiler »

aliqot wrote: post #5
082349872349872 wrote: post #3

6f 6e 65 20 69 66 20 62 79 20 6c 61 6e 64 2c 20 74 77 6f 20 69 66 2e 2e 2e

by sea..

The OP message is made of ascii ordinals encoded in hexadecimal. That led me to some interesting ideas based on fooling your adversary into thinking they had cracked your code, when they had in fact missed a hidden message:

1/ In the above example the message was “one if by land two if by…” and the encoding base was hexadecimal. Does a message exist that encodes in a different base but looks like it is hexadecimal? For example the OP’s message decodes to utk"ol"h if the base was actually 17. We assume it’s base16 not base17 because only the digits 0-F are used. Is there a string of pairs of digits in the range 0-F (without G) that would decode to something meaningful in base 17 (0-G)?

2/ And what about a message that means two different things — something innocuous in base16, with the secret message in base17, say? Other bases might work: 15 feels like a good candidate too, but it is probably harder to make a readable message the more you deviate from the masquerade base.

Re: Number Stations and Enigma Stations

#12

Post by wkat4242 »

geoffeg wrote: post #6

I assume most numbers stations have disappeared in part due to the proliferation of global internet access. But I've kinda wondered, how does that work? One of the benefits of numbers stations is that it was nearly impossible to determine who was listening to a shortwave radio station. Any internet resource someone visits would be traceable by the government. Even with SSL nearly everywhere it's not nearly as anonymo…

I guess that's where tor and similar techniques come in. Don't forget it was created by the DoD for just that purpose.

And it's not impossible to locate a shortwave listener (especially in the days when numbers stations were commonplace). At really short range it's possible to detect the local oscillator though modern direct conversion techniques make this harder.

In the 80s some countries were using this principle to identify people watching TV without a license.

Re: Number Stations and Enigma Stations

#13

Post by anonymousiam »

geoffeg wrote: post #6

I assume most numbers stations have disappeared in part due to the proliferation of global internet access. But I've kinda wondered, how does that work? One of the benefits of numbers stations is that it was nearly impossible to determine who was listening to a shortwave radio station. Any internet resource someone visits would be traceable by the government. Even with SSL nearly everywhere it's not nearly as anonymo…

I would say that's a bad assumption. National intelligence services routinely collect and analyze Internet traffic -- especially international traffic. Most are unable to analyze everything, but they'll keep an archive so they can go back later and look at something specific if needed. Also, I would assume they've got some AI looking for trends and also flagging "unusual" traffic for further (human) review. These HF stations are perfect for untraceable one-way traffic to foreign intelligence operatives.

Re: Number Stations and Enigma Stations

#14

Post by anonymousiam »

wkat4242 wrote: post #12
geoffeg wrote: post #6

I assume most numbers stations have disappeared in part due to the proliferation of global internet access. But I've kinda wondered, how does that work? One of the benefits of numbers stations is that it was nearly impossible to determine who was listening to a shortwave radio station. Any internet resource someone visits would be traceable by the government. Even with SSL nearly everywhere it's not nearly as anonymo…

I guess that's where tor and similar techniques come in. Don't forget it was created by the DoD for just that purpose. And it's not impossible to locate a shortwave listener (especially in the days when numbers stations were commonplace). At really short range it's possible to detect the local oscillator though modern direct conversion techniques make this harder. In the 80s some countries were using this principle t…

What you say about locating SW receivers may have been true in the era of superhetrodyne receivers, but today, in the era of direct digital sampling, it's no longer true. Old superhet receivers would leak the LO through the mixer out to the antenna so nearby detectors could deduce where the receiver was and what it was tuned to (assuming a standard IF, which is a fair assumption given the plethora of high-Q 455KHz and 10.7MHz ceramic filters).

Nowadays with a good digital receiver, nothing leaks from the receiving antenna.

Re: Number Stations and Enigma Stations

#15

Post by 082349872349872 »

geoffeg wrote: post #6

I assume most numbers stations have disappeared in part due to the proliferation of global internet access. But I've kinda wondered, how does that work? One of the benefits of numbers stations is that it was nearly impossible to determine who was listening to a shortwave radio station. Any internet resource someone visits would be traceable by the government. Even with SSL nearly everywhere it's not nearly as anonymo…

In WWII, censors were deeply suspicious of knitting patterns sent through the mails. These days, unless they find your decoder app, who's to notice if the numbers have been steganographically covered in a gigabyte or two of the internet's favourite: cat videos?

(and why does google give me a map of Latvia for an image search of "rule 34 russian woodpecker"? cf https://kartinkof.club/uploads/posts/2022-07/1657128790_10-k... )

Re: Number Stations and Enigma Stations

#16

Post by djaouen »

gorgoiler wrote: post #11
aliqot wrote: post #5

Earlier quoted context omitted.

by sea..

The OP message is made of ascii ordinals encoded in hexadecimal. That led me to some interesting ideas based on fooling your adversary into thinking they had cracked your code, when they had in fact missed a hidden message: 1/ In the above example the message was “one if by land two if by…” and the encoding base was hexadecimal. Does a message exist that encodes in a different base but looks like it is hexadecimal? F…

16 --> 15 would be a good candidate, as everyone would assume base 16 and you could use the full character set in your (secret) base 15 message. Too lazy to test it out, but theoretically plausible.

Re: Number Stations and Enigma Stations

#17

Post by anonymousiam »

gorgoiler wrote: post #11
aliqot wrote: post #5

Earlier quoted context omitted.

by sea..

The OP message is made of ascii ordinals encoded in hexadecimal. That led me to some interesting ideas based on fooling your adversary into thinking they had cracked your code, when they had in fact missed a hidden message: 1/ In the above example the message was “one if by land two if by…” and the encoding base was hexadecimal. Does a message exist that encodes in a different base but looks like it is hexadecimal? F…

41 74 20 44 45 46 43 4F 4E 2C 20 49 20 68 61 76 65 20 6D 65 74 20 67 6F 76 65 72 6E 6D 65 6E 74 20 53 49 47 49 4E 54 2F 43 52 59 50 54 4F 20 70 65 6F 70 6C 65 20 77 68 6F 20 63 6F 75 6C 64 20 63 6F 75 6C 64 20 6C 6F 6F 6B 20 61 74 20 61 20 73 74 72 65 61 6D 20 6F 66 20 68 65 78 20 62 79 74 65 73 20 61 6E 64 20 72 65 61 64 20 74 68 65 6D 20 69 6E 20 74 68 65 69 72 20 68 65 61 64 20 73 65 61 6D 6C 65 73 73 6C 79 2E

Re: Number Stations and Enigma Stations

#18

Post by nostrilwig »

geoffeg wrote: post #6

I assume most numbers stations have disappeared in part due to the proliferation of global internet access. But I've kinda wondered, how does that work? One of the benefits of numbers stations is that it was nearly impossible to determine who was listening to a shortwave radio station. Any internet resource someone visits would be traceable by the government. Even with SSL nearly everywhere it's not nearly as anonymo…

Maybe there are less than in then "golden days", but take a look at https://priyom.org/ to get some first-hand experience. EDIT: This site features a schedule/calendar with links to several webSDR sites, making it very easy the hear some of those transmissions live.

Re: Number Stations and Enigma Stations

#19

Post by djaouen »

082349872349872 wrote: post #15
geoffeg wrote: post #6

I assume most numbers stations have disappeared in part due to the proliferation of global internet access. But I've kinda wondered, how does that work? One of the benefits of numbers stations is that it was nearly impossible to determine who was listening to a shortwave radio station. Any internet resource someone visits would be traceable by the government. Even with SSL nearly everywhere it's not nearly as anonymo…

In WWII, censors were deeply suspicious of knitting patterns sent through the mails. These days, unless they find your decoder app, who's to notice if the numbers have been steganographically covered in a gigabyte or two of the internet's favourite: cat videos? (and why does google give me a map of Latvia for an image search of "rule 34 russian woodpecker"? cf https://kartinkof.club/uploads/posts/2022-07/1657128790_1…

I have a hunch that 4chan used to pass around rule 34 images steganographically in other images, but I was too lazy and too horrified of what I might see to find out for myself.
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