https://en.m.wikipedia.org/wiki/Hashcash
Having users to pay actions make spam unprofitable, as spam relies on tragedy of commons and abusing public goods. This is why there is so much less SMS spam compared to email spam.
https://en.m.wikipedia.org/wiki/Hashcash
Having users to pay actions make spam unprofitable, as spam relies on tragedy of commons and abusing public goods. This is why there is so much less SMS spam compared to email spam.