Bitcoin in Venezuela

[arnoudk]

I spent a few hours this evening talking to someone from Venezuela.

I was intrigued by something he said. He mentioned that he would never take his mobile phone with him - and at the very least step off of the street before using it. This out of fear for getting robbed.

Bitcoin has a lot of potential in Venezuela I think, but I thought this was an interesting perspective.

Does anyone have any solutions to using bitcoin in the scenario that you don't want to risk your phone being stolen?

[CryptAxe]

If you trusted the merchant I think you could use a paper wallet, that could obviously also be stolen though. The kiosk would need to be very secure so that it isn't stolen from the merchant as well it sounds like. The best solution I can think of would be for the merchant to allow customers to pay ahead of time from their homes and come pick up whatever they order, or keep some kind of account with the customer and allow them to fund their account with bitcoin.

[arnoudk]

Thanks something like that might actually work.

I like the prepay in bitcoin per merchant model. You could combine this with paper transactions (not wallets but presigned transactions to the merchant account that is unique to you).

You can carry TX with you and all a thief could do is submit them and fund your accounts at various merchants but not steal the funds.

All that is needed is to be able to print a TX as a qr code. And a prior exchange of wallet addresses.

Do qr TX codes exist? If not we could create them (assuming the amount of data fits - and else we could use multiple qr codes per tx).

[arnoudk]

If you add a third party you might even be able to do something like this :

Put funds in say $10 tx inputs of 2/3 multisig. One sig is in your safe, one on your pc and one at the third party.

Per tx output you sign a anyone can spend tx. And with the corresponding private key you also authenticate a message to the third party that the funds can only go to address a, b, c, d or e.

Your merchant scans the partially signed transaction AND the signed message, adds his own bitcoin address and sends it to this third party.

This third party will co sign only if the first sig is valid and if the signed message with the first sig contains the specified output address.

I'd have to look into the transaction types more closely to see if this could work but my gut feeling says that this is possible.

[BitcoinXio]

How does he spend money then? Does he carry cash? Cash is more easily stolen in my opinion. At least if my phone is stolen, it's protected by a pin, I can remote wipe it, and I have my private key to my spending wallet backed up. Cash, once it's gone, it's gone. Does he use credit card instead? That can be stolen also. I guess I don't follow the logic of fear of theft when anything of value can be stolen.

[arnoudk]

If you carry a transaction that goes to a select number of target addresses (and nothing else) they can steal your piece of paper. They can send the funds to any address you have whitelisted - but nowhere else.

If those addresses are owned by the merchants that you do business with then your funds is money only to them. You cannot send them elsewhere with that piece of paper. You could of course send them elsewhere by using your private key.

If you extend this and if the merchant links an address to you or to something you know - then only you can spend the funds at the merchants you have preselected.

So

You can see these pieces of paper as receipts for bitcoin and who can claim it is limited by the cryptography.

So I could print $1 $5 or $10 banknotes that only I can spend at merchants that I choose. So I can leave home with unstealable cash that only I can spend! I don't have to decide where I will buy something before leaving.

I would also add a change address in the code that has the allowed addresses.

I can make this completely offline. Somehow I would need the transaction ids for my addresses only.