Topic: Instant Bitcoin confirmation time (IDEA) - page 2. (Read 28766 times)

Please enlighten us on how to do so.

You may not like the current implementation of green addresses, but it's actually very easy to use multisig to make user-specific green addresses where your money can't be stolen, or frozen (if the cosigner disappears of the internet) for more than a few days. If that ends up being required to keep zero-conf safe, it will be deployed and used widely. We don't need to introduce new features to deal with zero confirmation security.

Replies such as these are naive and childish, why should we bother with the security of the bank said the guard, they could put things in their pocket and walk outside anyway.


Green addresses are a bad idea, currently the Bitcoin network doesn't try to resolve double spends in any way, using my method we could at the very least reach a lower rate of scammers.

If it is a problem a solution already exists, use of a green address. Usually they are offered by web wallets but they don't have to be.

I don't think it will be a problem in South Africa either. Or even Uganda or Nigeria or anywhere.

And your "Instant Bitcoins confirmation time" would keep them from putting products in their pocket and walking out of the store?

It would become a problem when wretched fools will start stealing from the hardworking people of Africa, same thing as with their governments currency being faked into oblivion.

And this is a problem?

It might not be a common occurrence in your community looking through your narrow perception but it WILL become a common occurrence if it would happen in south Africa or other countries where some people live in complete poverty while others get to enjoy the fine things in life.

They already have. And since bitcoin transactions happen over a network, you may even be guilty of wire fraud if you did a double spend attack. That's much more serious than just stuffing something in your pocket.

But just because it is possible to double spend doesn't mean it will be a common occurrence. Most grocery stores where I live now have self checkout lanes that aren't even monitored. Does theft happen? Sure. But most people don't try to steal.

Please do.

Dude, I could write up a double spend button in a custom Bitcoin client, the police would never pursue Bitcoin crime.

Exactly, zero confirmations.  This should be good enough for most point-of-sales purchases (like groceries) in my opinion.  As AliceWonder has outlined, if someone intends to steal low-value items from the shop, they will surely find a much simpler way than performing a double spend.  So confirmations are really only necessary for high-value purchases like cars or high-end electronic products and so, where the effort and risk associated to a double-spend is worth it.  In that case (think a car) it isn't a big problem to wait for the confirmations.

Who would wait 10 minutes for confirmation while in line? Or do you propose 0 conf?

The solution is green address.

Actually the solution is to not worry about it, it is really just another form of shoplifting. People who want to steal will find a way, and going through the register line is a bad way to do it because most places you will be caught on camera and eventually caught by law enforcement.

But double spends will be rarely attempted and I suspect the losses will likely be less than what is currently lost in debit/credit card transaction fees and chargebacks.

But we'd know that the first ones would propagate rapidly through the network, so we could divide the funds between the first 6 for example, since the probability of the 7th one being the legitimate double spend is low.

It doesn't cost anything to make a transaction. An attacker can create 1000 double spends.

That's why I propose to divide all the funds equally between every double spend, surely there haven't been 30 double spends.

Computer code cannot detect which is the "legitimate" double spend or which is the "attacker" double spend. They only know which transaction they themselves heard first.

Well you could make Bitcoin clients relay transaction with or without fees, you wouldn't need any private key at all because the 51% would decide who the coins rightfully belong to and include it in a block. We could also give the miners an additional fee for the dispute in order to reward them and make propagation more rapid.

I would love for people to start using Bitcoin on the high street, my life would be so much better in so many ways. But waiting even 10 seconds for a transaction (EFTPOS, VISA, etc....) is unacceptable. We either use 0 confirmations with at least the minimum fee and let the customer walk straight away or use a layer on top such as Bitpay. (If this takes off eventually VISA and MasterCard may support Bitcoin too)

The added benefit of a layer on top of Bitcoin is that we can pay in Bitcoin and the merchant can choose to have the transaction instantly converted into local fiat or remain as Bitcoin. (This will increase adoption)

If people are forced to wait 10 minutes for Bitcoin transactions ever (on the high street) this will forever destroy the reputation of Bitcoin in the minds of normal non Bitcoin people.


If the first transaction is 0 fee it might take some time to be included into blocks, the double spend with a fee then propagates faster before the first confirmation and eventually >50% of the network will see only 1 transaction. This might not happen all the time but it makes automated detection of double spends difficult. Your idea relies on the Bitcoin network always being able to detect the double spends correctly.

Also how do you move the coins without having the private key? This might be the most difficult part of your idea.