[bduerst]

Theoretically Monero would be a possible solution, but only if your sole requirement is anonymity. Heavy emphasis on only if though, since payment systems are much, much more than that requirement (i.e. dispute handling, chargebacks, insurance, fraud identification, etc.).

I don't think there are any crypto implementations today that could compete with existing mainstream systems, which in itself is a statement that opens a can of worms on HN, but maybe someday.

[guelo]

As if the store that can't be bothered to accept cash is going to accept some hard to use fringe coin.

[koonsolo]

That depends how you look at it. Crypto also has other advantages that payment systems haven't: any arbritary amount from 0.00001 to millions in 1 go, instant (especially advantage for the large numbers, since banks cannot do that), smart contracts etc.

Dispute handling and chargebacks are also very disputable for wire transfers. I have to give my ID to the bank every few years, yet people get scammed with wire transfers all the time and get a "sorry can't do anything about your lost money" from the bank.

[est31]

> instant (especially advantage for the large numbers, since banks cannot do that)

It's not instant. According to https://www.crypto51.app/ the cost to 51% attack ethereum for 1 hour is $92k. This means it's $2.2 million for one day or 24 hours. Let's say you want to transfer $10 million via ethereum. Then the party who gives you the eth can perform a double spending attack, only pretending to give you the $10 million while getting something else from you in exchange as part of the original deal that takes one day to be transfferred to them. As long as that something else is worth more than $2.2 million, that other party has made a return. The only good remedy is waiting for the double spending cost to exceed the contract volume, but it means that the currency isn't instant any more, or at least is instant for small sums of money only.

[koonsolo]

Your whole argument falls to pieces when Proof Of Stake is used instead of Proof Of Work. Plenty of high TPS crypto's use POS.

https://blog.qtum.org/how-proof-of-stake-renders-a-51-attack...

[PeterisP]

What do you mean by "especially advantage for the large numbers, since banks cannot do that" ?

Bitcoin requires a validation cycle or two in order to be certain that your transaction is going to be on the main chain, so it's 10-20 minutes.

For traditional infrastructure, the RTGS (real time gross settlement systems) accessible to banks and large customers handle transactions in seconds. If you're in a treasury department of a company who routinely needs to move large amounts around, doing so nearly instantaneously is absolutely a solved problem.

[koonsolo]

> is absolutely a solved problem

I'm going to sell my car on Sunday to another private person. I will hand over the documents and keys, while he instantly wire transfers me 20k.

Now all of a sudden it's not a solved problem anymore is it?

And Bitcoin, please, that's old tech. There are way more advanced cryptocurrencies now that have high TPS and < 10 sec validation.

[bduerst]

Punching holes in certain payment methods (like money wires) isn't the same as building a case for crypto.

Also crypto isn't instant. Bitcoin takes 10 minutes if you're lucky, even longer if the network is maxed at 7 transactions a second (comparatively, Visa handles 42,000 transactions a second).

[topranks]

While that’s correct that is also just an artificial limit put on it by the Bitcoin core devs, who somehow think it is desirable.

Many other coins have the capability to support orders of magnitude more transactions per second and have been successfully demonstrated to do so.

In theory, with 10GB blocks or so, it could scale to Visa-levels although I’m not sure anyone has tested at that scale.

[topranks]

The problem being discussed is replacing cash.

Cash does not provide dispute handling, chargebacks or any of those other things either.