[GreenKeys] Fwd: Re: Interesting images and reading!

[Jim Haynes]

Well the general answer is "offline encryption" meaning that somebody
encrypted the message into those groups using a separate machine, and
then the message sending people transmitted the scrambled text as it
was given to them.  And at the receiving end the message was handed
over to the crypto people to decrypt using another machine.  It took
a while before encryption was generally done online.