-Overall security on the client side is concentrated in passphrase
-(high-entropy password), so it is convenient to use it in GoVPN
-directly, without static on-disk keys. That is why we use passphrase
-authenticated key agreement.
-
-We use "passphrase" term instead of "password". Technically there may be
-no difference between them. But as a rule passphrases are @strong{long}
-strings with low entropy characters. Because of low entropy characters,
-they are memorable. Because of their quantity, they acts as a high
-entropy source.
-