This reminds me of OpenSSH's fingerprint visualization support ("VisualHostKey yes"):

    $ ssh A.B.C.D
    Host key fingerprint is b0:c9:c9:96:fb:fd:ac:a4:ff:70:8f:1b:35:f4:f9:2e
    +--[ECDSA  256]---+
    |                 |
    |                 |
    |      .       .  |
    |     o *     . ..|
    |      O S     o..|
    |     . .     . ..|
    |      .   o o   .|
    |       . + + +E. |
    |        o.++*....|
    +-----------------+
    
    me@A.B.C.D's password:

Original article introducing this feature: http://www.undeadly.org/cgi?action=article&sid=200806150... (2008/06/26).