It basically boils down to making the browser do some cpu heavy calculations before allowing access. This is no problem for a single user, but for a bot farm this would increase the amount of compute power they need 100x or more.

[–] Mubelotix@jlai.lu 77 points 5 days ago (2 children)

Exactly. It's called proof-of-work and was originally invented to reduce spam emails but was later used by Bitcoin to control its growth speed

[–] JackbyDev@programming.dev 8 points 5 days ago (2 children)

It's funby that older captchas could be viewed as proof of work algorithms now because image recognition is so good. (From using captchas.)

[–] Mubelotix@jlai.lu 6 points 4 days ago* (last edited 4 days ago)

Interesting stance. I have bought many tens of thousand of captcha soves for legitimate reasons, and I have now completely lost faith in them

[–] Ferk@lemmy.ml 1 points 4 days ago* (last edited 4 days ago)

That's actually a good idea. A very simple "click the frog" captcha might be solvable by an AI but it would work as a way to make it more expensive for crawlers without wasting compute resources (energy!) on the user or slowing down old devices to a crawl. So in some ways it could be a better alternative to Anubis.

[–] RandomTester@lemmybefree.net 4 points 5 days ago (1 children)

it wasn't made for bitcoin originally? didn't know that!

[–] 0xebfe@lemmy.today 11 points 5 days ago (2 children)

Originally called hashcash: http://hashcash.org/

[–] RandomTester@lemmybefree.net 12 points 5 days ago

you know it's old when it doesn't have ssl

[–] daw@feddit.org 3 points 5 days ago

TIL

[–] exu@feditown.com 12 points 5 days ago

It inherently blocks a lot of the simpler bots by requiring JavaScript as well.

[–] lazynooblet@lazysoci.al 7 points 5 days ago

Thank you for the link. Good read