>the problem appeared to be a hardware fault and they did not believe their system had been hacked
https://en.wikipedia.org/wiki/Robert_Kagan
>I'm talking about the internal wounds that do not heal.
Alice In Chains - Man in the Box
https://en.wikipedia.org/wiki/Shave_and_a_Haircut
The former prisoner of war and U.S. Navy seaman Doug Hegdahl reports fellow U.S. captives in the Vietnam War would authenticate a new prisoner's U.S. identity by using "Shave and a Haircut" as a shibboleth, tapping the first five notes against a cell wall and waiting for the appropriate response. U.S. POWs were then able to communicate securely with one another via the quadratic alphabet code.
https://en.wikipedia.org/wiki/Tap_code
knock code, is a way to encode text messages on a letter-by-letter basis in a very simple way. The message is transmitted using a series of tap sounds, hence its name.
The tap code has been commonly used by prisoners to communicate with each other. The method of communicating is usually by tapping either the metal bars, pipes or the walls inside a cell.
The tap code is based on a Polybius square using a 5×5 grid of letters representing all the letters of the Latin alphabet, except for K, which is represented by C.
Each letter is communicated by tapping two numbers, the first designating the row and the second (after a pause) designating the column. For example, to specify the letter "B", one taps once, pauses, and then taps twice. The listener only needs to discriminate the timing of the taps to isolate letters.
>Man in the Box
The origins of this encoding go back to the Polybius square of Ancient Greece. Like the "knock code", a Cyrillic script version is said to have been used by nihilist prisoners of the Russian czars.
https://en.wikipedia.org/wiki/Polybius_square
Polybius checkerboard, is a device invented by the ancient Greeks Cleoxenus and Democleitus, and made famous by the historian and scholar Polybius. The device is used for fractionating plaintext characters so that they can be represented by a smaller set of symbols, which is useful for telegraphy, steganography, and cryptography. The device was originally used for fire signalling, allowing for the coded transmission of any message.
>Hunter Biden’s biolab METABIOTA