randomart in ssh (nerd alert!)
Today I learned about randomart in ssh. It generates random ASCII art from ssh keys. Think old-skool BBS art generated with letters, numbers, and punctuation. SSH is a command-line utility for connecting to remote servers. It uses cryptographic keys to secure the connection so it can't be eavesdropped on by folks in the middle (using a network sniffer, for example).
Anyway, ssh keys are long strings of characters, and they are easy to verify with a computer, but difficult for humans to verify visually. Changing even one character in a key makes it into a different key, and that would be hard for humans to detect easily and routinely.
So, the authors of ssh, an Open Source tool, implemented a feature that generates a unique picture (but the same one every time for a specific key). If you regularly ssh to a server, it's anticipated that you'd notice any changes to that picture.
The key fingerprint is:
SHA256:o5lJ57gY1oUS+VIMP/KU7T5varCH+6Xsc+M0/BXyHUw HaX0r@shell
The key's randomart image is:
+---[RSA 2048]----+
| . |
| = o |
| + B . E |
| B + o |
| o = S . .o |
| =.@ o o o.|
| o B++ = o .|
| . ooo+*+o . |
| . o***o.. |
+----[SHA256]-----+
Read more and turn it on for your ssh config. Pretty cool! https://superuser.com/questions/22535/what-is-randomart-produced-by-ssh-keygen <- lots more cool links from here.
Note: unless you are a nerd who uses the command line in Linux or MacOS, you will not likely find this useful, but I hope you still find it interesting.
Also: https://blog.benjojo.co.uk/post/ssh-randomart-how-does-it-work-art
Anyway, ssh keys are long strings of characters, and they are easy to verify with a computer, but difficult for humans to verify visually. Changing even one character in a key makes it into a different key, and that would be hard for humans to detect easily and routinely.
So, the authors of ssh, an Open Source tool, implemented a feature that generates a unique picture (but the same one every time for a specific key). If you regularly ssh to a server, it's anticipated that you'd notice any changes to that picture.
The key fingerprint is:
SHA256:o5lJ57gY1oUS+VIMP/KU7T5varCH+6Xsc+M0/BXyHUw HaX0r@shell
The key's randomart image is:
+---[RSA 2048]----+
| . |
| = o |
| + B . E |
| B + o |
| o = S . .o |
| =.@ o o o.|
| o B++ = o .|
| . ooo+*+o . |
| . o***o.. |
+----[SHA256]-----+
Note: unless you are a nerd who uses the command line in Linux or MacOS, you will not likely find this useful, but I hope you still find it interesting.
Also: https://blog.benjojo.co.uk/post/ssh-randomart-how-does-it-work-art
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