The Bombe was the device used to decipher encrypted messages from the Enigma machine during World War II.
(The Bombe in The Imitation Game)
In S5E2, Robin even mentions the Enigma machine.
However, what she says is incorrect. The Enigma machine didn't win the war. In fact, it was used by the side that lost.
What did help win the war? The Bombe, which was created by Alan Turing.
Who is also referred to as the key.
Alan Turing's Bombe helped decipher the Enigma machine's encrypted messages by determining its key settings (more about this here if you're interested). In other words, the key settings of the sender and the receiver had to match up in order for the messages to be deciphered.
This process reminds me of the encryption/decryption process used by computers.
Ciphertext is the unreadable/scrambled form of text, whereas plaintext is the readable form.
Which reminds me of this:
Where ciphertext cycles through possible characters, until the plaintext emerges, revealing the message. (video)
Which I interpret as "When blue and yellow meet in the west, run program SilverCatFeeds," which potentially is a program that's altering people's memories.
Going back to the encryption/decryption diagram:
The "interceptor" refers to a third party who gains access to encrypted data.
There are multiple methods of interception. I found this one interesting:
So if the interceptor has access to the data, then they can alter it as well.
What's the solution to the interceptor problem?
To go dark. (@misspracticallydelulu)
The interceptor loses access to the data, and therefore, can no longer alter it.
And there are many ways "to go dark", but I think that may be for another post!
(This post was inspired by @gritstartar's post about keys and cryptology.)