The issue with browser based PoW is that browsers are still fairly slow execution environments.
Any waiting period for calculation that won't annoy users is not long enough for an attacker to not still be able to spam, given that they will be solving them 2-100x faster with an optimized native implementation vs in a browser.
It also doesn't work as a turing test, because by their nature computers are good at batch solving proofs of work.
I once started an anonymous email service with browser-based PoW for antispam. It didn't work.
You'd need users to do like, several hours of in-browser PoW to make it viable as an anti-abuse measure. Anything less means a bot farm is posting spam dozens of times per hour.
Frictionless micropayments are still a pipe dream today, as any useful technology available to do so has basically been outlawed in the USA without a multimillion dollar license, and a KYC department, et c. It's a real shame because we have all of the technology for cash-based anti-abuse bonds and the like. It's just illegal to deploy it unless
you go full MSB.
Money services business, a heavily regulated industry in the USA due to the USG’s insistence upon total identity-linked financial surveillance for all end users of all financial service providers in the country.
Not only is it a total privacy invasion, all the burden is borne by the service providers for implementing the government’s universal financial surveillance.
Any waiting period for calculation that won't annoy users is not long enough for an attacker to not still be able to spam, given that they will be solving them 2-100x faster with an optimized native implementation vs in a browser.
It also doesn't work as a turing test, because by their nature computers are good at batch solving proofs of work.
I once started an anonymous email service with browser-based PoW for antispam. It didn't work.
You'd need users to do like, several hours of in-browser PoW to make it viable as an anti-abuse measure. Anything less means a bot farm is posting spam dozens of times per hour.
Frictionless micropayments are still a pipe dream today, as any useful technology available to do so has basically been outlawed in the USA without a multimillion dollar license, and a KYC department, et c. It's a real shame because we have all of the technology for cash-based anti-abuse bonds and the like. It's just illegal to deploy it unless you go full MSB.