alt Hacker News> ...we have tried to minimize the impact on real readers as much as possible. We have not gone with tools like Anubis, partly because it causes annoying delays for those trying to get to the site, but also partly because it seems inevitable that the scrapers will eventually find their way around it. Indeed, there are some indications that is already happening. A proof-of-work requirement is not a huge obstacle when you have millions of other people's machines to do the work on.
It's massively less annoying than a captcha, which is both a longer delay (typically, at present) and a massive cognitive distraction/roadblock.
The anubis author has stated they recognize it's an arms race, but PoW scales. Captchas and other signals are already at the end of the road; any additional difficulty increases false bot-positives, which are already unacceptably high.
For websites running dynamic languages, a binary (anubis is in go) sentry that operates before[1] the website is forced to expend any resources, is usually a large improvement over a site-hosted captcha. I would rather, and I think most humans would agree, have to wait a few seconds, maybe even closer to a minute in the future, to get a website access token good for a day or a week, than be forced to solve a captcha.
The dilemma for bots: when tokens are bound to the connecting ip, scrapers must limit the connecting IP pool for each site they want to scrape, becoming much more obvious and easy to block, or they have to use massive amounts of compute.
[1] this is true regardless of whether anubis is in reverse proxy mode or auth mode.
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Anubis is by far the least annoying throttler I encounter. Entirely agreed, just crank it up when you get a flood, I much prefer waiting a couple seconds to interacting with custom UI for tens of seconds.
I'm so glad to see that (essentially) HashCash is coming back. Now we just need it for email, like it was originally designed for...
PoW barely affects the "residential proxies" aka. malware botfarms. The IPs are free for them and siphoning additional system resources for PoW doesn't matter at all for them. PoW only affects the large centralised scraping by the AI providers, which are not operating behind "residential proxies".
> The anubis author has stated they recognize it's an arms race, but PoW scales.
The scraper wars are largely between script kiddies and people with both deep intimate networking and DOM knowledge. Yes greyhairs, I’m looking at you.
The problem is, you can’t PoW every page load and resource request because the user experience will suck and people will run away. And that window - the gap between what people will tolerate vs draconian enforcement - is exactly what the scrapers exploit.
And looking at the PoW options out there - I’ve seen at least one PoW WAF (honestly can’t remember if azure or amazon) have their PoW boil down to repeated trigonometric functions, ie very optimisable.
It’s a neat concept, but the answer and future to my eyes look bleak.
I don't think PoW scales, because if the bot authors get serious they'll start using native implementations that are much more efficient than the web ones real users are running. In theory maybe Anubis could start using WebGPU to help close that gap, but then anyone without WebGPU support is out of luck.
Then again, a large portion of the problem seems to be bots making way too many requests and in general not being optimized in the first place, and this does help filter those out.
At least anubis works for me. (I run umatrix)
Unfortunately whatever HN is using routinely blocks my login with "Sorry."
some websites just always give me 403.
Well, we don't use a captcha either. If it were a choice between a captcha and a proof of work system, we'd have to reevaluate things. Luckily, for now, we're able to get away with a much lighter touch.
> but PoW scales
Not if the honest party is doing it in a browser: The same computer can so any POW so much faster in C than any amount jf JS and WASM that it will never ever ever be a contest.
> becoming much more obvious and easy to block, or they have to use massive amounts of compute.
If you believe this, please contact me: I think compute is free[1] and can probably help you out.
Or you can go full Reddit and just block anything that seems even remotely suspicious.
Your sibling, roommate, neighbor that uses your internet, previous IP owner, posts too much? You get blocked too.
Using VPN? Blocked.
Your iPhone is too old, blocked.
Your screen brightness too low? Believe or not, blocked.
> The dilemma for bots: when tokens are bound to the connecting ip, scrapers must limit the connecting IP pool for each site they want to scrape, becoming much more obvious and easy to block, or they have to use massive amounts of compute.
You can't do that any more. Too many ISPs, especially mobile carriers, don't hand out anything resembling a fixed IP address any more. It's CGNAT and constantly changing IP addresses alllll the time now.
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PoW can theoretically scale effectively infinite because it can mine cryptocurrency. Millions of compromised IoT devices hitting your server? Now you have enough money for a faster server.
It doesn’t matter that the challenge must be verified: present multiple challenges, some are verified while others mine crypto.
Proof of work does not scale. It trades something fungible and incredibly cheap (CPU) for something incredibly expensive (user-visible latency). There is no set of parameters where the cost is going to be a meaningful deterrent to any kind of abuse (even something as low-yield as scraping) without adding crippling amounts of latency to real users.
> The dilemma for bots: when tokens are bound to the connecting ip, scrapers must limit the connecting IP pool for each site they want to scrape, becoming much more obvious and easy to block, or they have to use massive amounts of compute.
There is no dilemma. They get a token, they maybe do some automated multi-armed bandit per-site to figure out how to maximize the extraction rate they get from a single token, and then they use an IP for that many requests / that amount of time before ditching it.