Physical Bitcoin for the 3rd World

[BitCheques]

Anyone interested?

I'd like to continue this discussion, but you should create another topic for it. If you do, feel free to mention me (@LoyceV)

To continue the discussion regarding the safe use of paper wallets as currency: [ANN] bitaddress.org Safe JavaScript Bitcoin address/private key https://bitcointalk.org/index.php?topic=43496.msg60193930#msg60193930

[BitCheques]

The Central African Republic has just declared Bitcoin to be legal tender, but 90% of the population doesn't have ready access to the Internet. I am exploring safe ways to use Bitcoin without having to connect to the Internet for every exchange. Ideally a paper wallet could be created in a manner that prevents anyone from memorizing or recording the private key before it is sealed.

I am also exploring a smart contract that guarantees (via escrowed funds and/or multisig) that no funds are released until the BitCheques are opened.

[LoyceV]

Quoting from the other topic:

Actually, there are some very good methods of selecting an arbitrator. For example, each party submits 3 arbitrators, from which one is chosen by the other party. The two arbitrators select a third. The panel of three decides (2 of 3) from between solutions submitted by each party without alteration as to what funds are released to what party. This prevents a "splitting the baby" compromise.

The main problem: no matter how good the arbitrator is, it's not trustless. If someone wants to pay me with a private payment system which means I have to trust some people I don't know, I wouldn't accept it. I'm not into Bitcoin to trust people, I'm into Bitcoin to be my own bank so to speak.

When a BitCheque is purchased from the issuer (me), guarantee funds are locked up for a specific time period and/or until it is redeemed. If an unopened BitCheque is emptied of funds, this would indicate fraud or carelessness on the part of the issuer, and trigger arbitration - if the issuer does not promptly compensate the holder.

So if you sell 1000 Bitcoin in BitCheques, you'll need to deposit 1000 Bitcoin accessible from the private keys on the BitCheques, and another 1000 Bitcoin in the arbitrators' posession. Who's going to fund that additional 1000 Bitcoin?

This type of contract can be written in Solidity or possibly a taproot layer.

We're a long way from smart contracts being common in Bitcoin, and if Ethereum is any indication of what's going to happen, nobody will truely understand the details.

The Central African Republic has just declared Bitcoin to be legal tender, but 90% of the population doesn't have ready access to the Internet.

I assume that percentage will only go up the coming years.

I am exploring safe ways to use Bitcoin without having to connect to the Internet for every exchange.

It's like sending an email: you can't do it without the internet. You can print the email and send a letter, but if you do, it's no longer an email.

Ideally a paper wallet could be created in a manner that prevents anyone from memorizing or recording the private key before it is sealed.

That's not possible. I can print a paper wallet with my eyes closed and seal it, but you'd have to trust me on this. I can setup an automated production line that seals the paper wallets before they come out, but you'd have to trust it doesn't store the private keys. You can watch me burn the production line, but you'd have to trust I didn't use pre-generated private keys. The only way to be sure nobody else knows your private keys, is by generating them by yourself.

I am also exploring a smart contract that guarantees (via escrowed funds and/or multisig) that no funds are released until the BitCheques are opened.

"Smart contracts" always remind me of Ethereum's DAO scam, in which they called the only person who understood the contract "The Attacker", after which they let go of their "code is law" and hardforked it into a centralized shitcoin. Let's not go there with Bitcoin.

[BitCheques]

Of course, complete trustlessness is an ideal toward which we strive. Most bitcoin transactions over the Internet don't meet that criteria either - especially if someone uses a custodian or widely shares his public address. Another ideal is simplicity. Having to memorize a password for transactions fails that test. Using bitcoin correctly requires a steep learning curve. A currency shouldn't.

Initially,  the guaranteed amount will likely be more like 10000 satoshis. As the production process becomes more secure and anti-counterfeiting measures are improved, larger denominations will become more feasible.

I believe that you greatly underestimate the potential of smart contracts. A complex DAO shouldn't be necessary in this case anyway.

The lightning network allows transactions to take place without being verified in real time. Paper notes would improve on portability.

[JeromeTash]

The Central African Republic has just declared Bitcoin to be legal tender, but 90% of the population doesn't have ready access to the Internet. 

Is Central African Republic really that badly off in terms of Internet access? I find that had to believe.
Where do people get such statistics, and who does them?

Ok assuming Central African Republic has a low internet usage rate, what guarantee is there that people will start using some new physical form of Bitcoin is not a trustless system like what the electronic form of Bitcoin?

[LoyceV]

Is Central African Republic really that badly off in terms of Internet access? I find that had to believe.

It seems correct:

Central African Republic has internet penetration rates of just 11%, equal to some 550,000 people online last year, the DataReportal website estimates. Meanwhile only around 14% of people have access to electricity and less than half have a mobile phone connection, the Economist Intelligence Unit says.

So many of the people without electricity have a mobile phone, which means they go somewhere to charge it. It's also one of the most expensive countries for mobile data.

[BitCheques]

Is Central African Republic really that badly off in terms of Internet access? I find that had to believe.
Where do people get such statistics, and who does them?

DIGITAL 2022: THE CENTRAL AFRICAN REPUBLIC
Internet use in the Central African Republic in 2022
https://datareportal.com/reports/digital-2022-central-african-republic?rq=Central%20African%20Republic

"The Central African Republic’s internet penetration rate stood at 7.1 percent of the total population at the start of 2022...For perspective, these user figures reveal that 4.61 million people in the Central African Republic did not use the internet at the start of 2022, meaning that 92.9 percent of the population remained offline at the beginning of the year."

[BitCheques]

Ok assuming Central African Republic has a low internet usage rate, what guarantee is there that people will start using some new physical form of Bitcoin is not a trustless system like what the electronic form of Bitcoin?

Since they don't have internet, they are left with two legal tender options: a fiat currency with a history and high probability of continued debasement, or a bitcoin note which is programmatically immune from debasement. Having had experience with fiat, the bitcoin note is more attractive. While bitcoin is currently volatile, a wider use of bitcoin will gradually stabilize it. Its value is also likely to continue increasing as it becomes more widespread internationally and halvings further cap the supply of bitcoin. It's our job to make BitCheques as trustless as possible.

[BitCheques]

I'm trying to reach Chris Cassano (glitch003 on github) to learn more about the security of the Piper Wallet printer's forget button, and to learn more about the history of the project. The Piper wallet was a self-contained Raspberry Pi bitcoin paper wallet generator developed 7 years ago that may provide helpful information going forward.

https://www.youtube.com/watch?v=rOcNWcLLG8c

https://github.com/piperwallet

[LoyceV]

Piper Wallet printer

Have you seen this topic?

[BitCheques]

Thanks! This could be a tremendous help!

[leea-1334]

But why do we have to think so extreme from paper to internet? I am sure there are other technologies in between that everyone in Africa can access like radio. Electricity I believe is the main problem but if you could have something like a radio that runs on batteries for weeks. I know I could be sounding nonsense but this is my thought and maybe a genius can point it out.

I mean, paper is great but I live in Asia and it is very humid and well,,, if you had important papers lying around there is someone ready to break into it.

Imagine if there is no internet what is the possibility they have good safes or safety deposit box?

[NeuroticFish]

But why do we have to think so extreme from paper to internet?

I tend to agree with this.

I am sure there are other technologies in between that everyone in Africa can access like radio. Electricity I believe is the main problem but if you could have something like a radio that runs on batteries for weeks. I know I could be sounding nonsense but this is my thought and maybe a genius can point it out.

One doesn't have to be genius, the forum has a lot of solutions gathered, just I don't know if they're properly centralized.

I've read about this in the past, but now the site seems to be down: https://satoshi.radio.br/
but I've found a copy: https://web.archive.org/web/20220405084343/https://satoshi.radio.br/wp/

Another one I've found and it's the first time I see it is https://txtenna.com/

Also don't forget the Opendime-like solutions as physical replacements for Bitcoin, although they're a bit expensive.

I mean, paper is great but I live in Asia and it is very humid and well,,, if you had important papers lying around there is someone ready to break into it.

Water and also fire are the first enemies of the paper one can think on, but human mistakes are just as bad - from misplacing it to forgetting what's it about and tear it into pieces and/or throw it away or spill something onto it.

Imagine if there is no internet what is the possibility they have good safes or safety deposit box?

I think that it makes more sense to keep something better than simple paper in safety deposits; from laminated paper to OpenDime or, if you have proper wallet then the seed can be even imprinted onto steel.

To continue the discussion regarding the safe use of paper wallets as currency

Maybe I'm missing something, but what if a malicious party create multiple copies (Xerox) of the same piece of paper?
I think that whatever you do right, somebody will get scammed, and from there to ruining your reputation is just a tiny step (no matter the scammer wasn't you).

[BitCheques]

Broadcasting transactions over the radio seems like a step backward. How would this increase privacy?

Dollar bills (which are currently used) are paper too. Let's take currency evolution one step at a time.

BitCheques are folded, sealed, and laminated (with the private key hidden inside). All this could eventually be done on a self-contained machine. But that would be phase 2. Having a storable paper wallet is an improvement over not having access to bitcoin at all. Making it into a physically exchangeable note is the bigger challenge (financially - not technologically). Hoppers, folders, and laminators are available off the shelf.

Trustability has been attained by bitaddress. The ability of a Piperesque machine to provably forget the private key is the objective. BitCheques are currently printed offline with the bitaddress tool. The only person that needs to be trusted now regarding not archiving the private key is me (the manufacturer). Having the BitCheques made locally (and automatically) helps to solve the trust problem because it removes the human element. It also negates the need for a supporting smart contract and/or escrow.

Right now, all that is needed is a segwit enabled Piper.

[NeuroticFish]

Broadcasting transactions over the radio seems like a step backward. How would this increase privacy?

Dollar bills (which are currently used) are paper too. Let's take currency evolution one step at a time.

BitCheques are folded, sealed, and laminated (with the private key hidden inside). All this could eventually be done on a self-contained machine. But that would be phase 2. Having a storable paper wallet is an improvement over not having access to bitcoin at all. Making it into a physically exchangeable note is the bigger challenge (financially - not technologically). Hoppers, folders, and laminators are available off the shelf.

Dollar bills are indeed paper too (special paper, still, OK). Just Dollar bills are IOU papers.
From my understanding BitCheques are something different and no matter how you fold and laminate the paper, somebody may counterfeit it. Since they are not IOU, when one will try to spend the underlying bitcoin and will see they were already spent, it won't be pretty.

But, again, I might have missed something, since the current collectibles kinda risk the same problem: somebody skilled enough could counterfeit them or sell them after peeking on the private key. I don't know though how the seal can be replaced with an identical one; but in your case, at least at first glance, it looks simpler.

[nullama]

After reading about the Bolt Card, which is basically an NFC card with an LNURL-Withdraw link stored in it, I'm wondering if it would be possible to mass produce coins or bills with cheap NFC in them so that the value of the physical thing is almost zero, but it holds certain amount of Bitcoin, verifiable somehow.

This solution probably will require some third party that basically escrows the funds, but if that's possible, then you would be able to trade bitcoin offline basically by just passing around those NFC enabled coins/bills.

I'm not sure if it would be possible to somehow confirm that the NFC holds certain amount of Bitcoin offline, but at a minimum it should be possible to check with an Internet connected phone, which are common in the developing world. Also it could be a device, like an ATM for example, shared among a group of people that could just go there to verify their coins/bills, without the need for them to have an internet connected device themselves.

I think this could be potentially more secure than a simple QR code printed out, since there are specialized NFC chips that protect for certain known attacks.

[BitCheques]

I like the durability of credit cards, but in the target market, vendors are not equipped for any electronic equipment. The bolt card seems to require a companion electronic wallet. Any nfc gurus out there?

[leea-1334]

I've read about this in the past, but now the site seems to be down: https://satoshi.radio.br/
but I've found a copy: https://web.archive.org/web/20220405084343/https://satoshi.radio.br/wp/

Another one I've found and it's the first time I see it is https://txtenna.com/

Also don't forget the Opendime-like solutions as physical replacements for Bitcoin, although they're a bit expensive.

Amazing,,, even I did not know of this and figures that somebody already thought about it. Radio in Brazil, it totally makes sense.

Broadcasting transactions over the radio seems like a step backward. How would this increase privacy?

Dollar bills (which are currently used) are paper too. Let's take currency evolution one step at a time.

I think privacy is something to figure out later,,, we want people to use them first. And if we are talking Africa then people are pretty 'private' already being many unelectronically documented

Dollar bills can be more secure as the tech to print it is much higher,,, we are talking material and I thought something like radio is underused layer that has high access in undeveloped places.

[NeuroticFish]

I like the durability of credit cards, but in the target market, vendors are not equipped for any electronic equipment. The bolt card seems to require a companion electronic wallet.

I find this a better path, although, yes, you have to do proper research here too.
I think that you can easily require a smartphone with NFC, it may be easier for everybody. I don't know though if only the merchant has to have the hardware, or will the customer have to have it too (in order to avoid troubles).

Satochip based hardware wallet works on NFC and its companion code is open source. Although I can guess it's not 100% what you need, you may gather some knowledge also from taking a look there. Just an idea...

[BitCheques]

CAR'S Sango Project seeks to make crypto "accessible to all".

https://cointelegraph.com/news/central-african-republic-to-launch-official-crypto-hub-sango