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Comment by Aachen | Hacker News Reader

> requiring 1 second of compute before allowing a page load

After 1 solve, you get a cookie and can load tons of pages with it. Scrapers and user agents alike will need to spend the compute only once to get a valid session for themselves

Seems to be working so far though. Fwiw, lots of silly things stop bots until someone puts their mind (or tokens) to bypassing it, and then the blocking mechanism has to adapt. We'll see how it plays out, for now it's a lot better than begging big brother (cloudflare, google, or amazon captcha) for access, so I'm quite appreciative of what Techaro is doing

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The issue is that scrapers are rotating their IP and essentially performing a DDoS attack. Anubis is part of a defense-in-depth solution. If scrapers reuse a cookie, traditional anti-abuse mechanisms will work.

>If scrapers reuse a cookie, traditional anti-abuse mechanisms will work.

Scrapers can't change their strategy? It's not hard to think of mitigations: keep on using a session until you're banned, and failing that rotate your IP. Nowadays you don't even need to think. You can probably tell a LLM "write me a scraper that has adaptive anti-anti-bot mechanism".

> Scrapers can't change their strategy?

Yes, but you normally don't try to fight all strategies up front, you add stuff on a need-to basis. Currently, lots of people are in the stage of "need to get this thing using bunch of IPs to stop hammering my servers", apparently Anubis helps them with that. If that stops working, other tactics are tried, and so it goes on for the life of your service. Hasn't stopped yet, doesn't seem to be stopped soon either.

That argument also works against anubis. Why bother forcing clients to solve a PoW challenge, when you're fighting a bunch of unsophisticated attackers that will be deterred by a javascript challenge that requires them to solve `result = x + y`?

This is why there's the meta refresh challenge as an option: https://anubis.techaro.lol/docs/admin/configuration/challeng...

Turns out that in practice there's some bots that implement support for this but not JavaScript.

Point is, you get problems because of something like this, you try either approach. And when that stops working (because eventually it will), you add something else. Some work better against some actors, but also feels like it never ends, so slowly you add more things. I don't think Anubis is uniquely able to stop that particular type of annoyance, it's just one of the tools you can see if it helps. If you want to try something else before, makes a lot of sense to do so.

You're not fighting unsophisticated attackers. 50% of them are, maybe. The rest? They're actively hostile, detecting blocking attempts, moving on to botnets, DDoSing you and trying everything they can to bypass you.

People have been sent to jail for participating in LOIC attacks which were less destructive that what these bots do on the daily.

Plenty of these abusive scrapers are utilizing retail residential proxies, which will be applying forced rotations to avoid "burning" their compromised and or otherwise surreptitiously utilized IP address.

I don't know what you mean by traditional anti-abuse (typing over two words from an image?), but switching IP addresses rapidly, while staying recognisable as one entity because of the unique cookie, is not normal user behavior so this would be trivial to filter out for something like Anubis and require another solve. Maybe that's what you meant though?

https://people.kernel.org/monsieuricon/creepy-crawlies reports anubis effectiveness falling off

I would disagree with the Anubis effectiveness falling off, but the llm bros are throwing life itself into training to defeat any “perceived” challenge.

If you change your IP address, it invalidates the cookie. If you don't change your IP address, you can be blocked by IP address.

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