That's what it's for, isn't it? Make crawling slower and more expensive. Shitty crawlers not being able to run the PoW efficiently or at all is just a plus. Although:
> which is trivial for them, as the post explains
Sadly the site's being hugged to death right now so I can't really tell if I'm missing part of your argument here.
> figure out that they can simply remove "Mozilla" from their user-agent
And flag themselves in the logs to get separately blocked or rate limited. Servers win if malicious bots identify themselves again, and forcing them to change the user agent does that.
The default settings produce a computational cost of milliseconds for a week of access. For this to be relevant it would have to be significantly more expensive to the point it would interfere with human access.
So a crawlers that goes very ethically and does very little strain on the server should indeed be able to crawl for a whole week on a cheap compute, one that hammers the server hard will not.
Provisioning new ips is probably more costly than calculating the tokens, at least with the default difficulty setting.
Perhaps you just don't realize how much did the scraping load increase in the last 2 years or so. If your server can stay up after deploying Anubis, you've already won.
If it's an actual botnet, then it's hijacked computers belonging to other people, who are the ones paying the power bills. The attacker doesn't care that each computer takes a long time to calculate. If you have 1000 computers each spending 5s/page, then your botnet can retrieve 200 pages/s.
If it's just a cloud deployment, still it has resources that vastly outstrip a normal person's.
The fundamental issue is that you can't serve example.com slower than a legitimate user on a crappy 10 year old laptop could tolerate, because that starts losing you real human users. So if let's say say user is happy to wait 5 seconds per page at most, then this is absolutely no obstacle to a modern 128 core Epyc. If you make it troublesome to the 128 core monster, then no normal person will find the site usable.
The way i think it works is they provide free VPN to the users or even pay their internet bill and then sell the access to their ip.
The client just connects to a vpn and has a residential exit IP.
The cost of the VPN is probably higher than the cost for the proof of work though.
In an endless cat-and-mouse game, it won't.
But right now, it does, as these bots tend to be really dumb (presumably, a more competent botnet user wouldn't have it do an equivalent of copying Wikipedia by crawling through its every single page in the first place). With a bit of luck, it will be enough until the bubble bursts and the problem is gone, and you won't need to deploy Anubis just to keep your server running anymore.
>> So (11508 websites * 2^16 sha256 operations) / 2^21, that’s about 6 minutes to mine enough tokens for every single Anubis deployment in the world. That means the cost of unrestricted crawler access to the internet for a week is approximately $0.
>> In fact, I don’t think we reach a single cent per month in compute costs until several million sites have deployed Anubis.
And as the poster mentioned if you are running an AI model you probably have GPUs to spare. Unlike the dev working from a 5 year old Thinkpad or their phone.
Indeed a new token should be requested per request; the tokens could also be pre-calculated, so that while the user is browsing a page, the browser could calculate tickets suitable to access the next likely browsing targets (e.g. the "next" button).
The biggest downside I see is that mobile devices would likely suffer. Possible the difficulty of the challange is/should be varied by other metrics, such as the number of requests arriving per time unit from a C-class network etc.
Luckily someone had already captured an archive snapshot: https://archive.ph/BSh1l
