Topic: Sending private keys instead of transactions - page 2. (Read 3188 times)

This would be done automatically by a client(extension), so no additional work.

Advantage is that an attacker has MUCH more difficult task when tracing payments.

Between trusted parties however, there's an advantage in that bitcoins can be transferred without a computer.  That's a huge advantage, it makes them within reach of more people, and that's a huge problem right now - many people who wouldn't mind owning a few bitcoins "for fun" get turned off by the idea of having to download a program or take a risk of getting hacked.

The local pawnshop, run by a completely computer-illiterate dude, could sell pre-made envelopes with 10 BTC in them for cash, prepared by someone else he trusts.  Or BitBills, with a human-readable private key instead of QR code.  He already deals in silver and gold, so the idea of looking up a current exchange rate isn't beyond his skill set.

Each BTC package contain a private key.  Maybe the Silk Road accepts private keys and the customer wants to score.  Sure, the pawnshop could steal the coins back from their own customer, but you can only do that so many times IRL before you get your ass kicked.  The recourse, in this case, is a practical one, rather than technical.

Advantage: The exact same number of bitcoins can change hands any number of times without any record in the public block chain.

Disadvantage: The person who is the rightful holder of the bitcoins can be screwed at any time by anyone in the chain before him. To avoid this disadvantage, he has to put a transfer in the public block chain, negating the advantage.

Analysis: Non-starter.

Welcome back, double spending!


What was the whole point of Bitcoin, the thing that has never been achieved before? I forgot.

The problem with sending a private key is that you don't know that the sender has destroyed his copy. So to be safe you would have to transfer the bitcoins to a different key anyway.

I don't see any possible advantages here?  If you ever received a private key from someone as payment, the very first thing you would do is generate a transaction to send all the coins from that private key to one of your own addresses that you know no one else has access to.  So any time money is transferred between two people you'd have to (a) send the private key and then (b) do a transaction to a non-shared address.  Just doing a normal transaction from the get-go is simpler.

Maybe this has a stupid drawback or has already been discussed - but let me just put a thought on the board for discussion.

Currently we send money by sealing transactions in a block chain. This approach is higzhly susceptible to network analysis attacks. Although the bitcoin addresses are pseudonyms, all transactions are public and you can follow payment streams. I am currently doing some analyses here, but that's a different story.

Now, suppose we did different:

Alice wants to send 5 BTC to Bob. So she prepares a fresh bitcoin address, posts 5 BTC to this address and sends the private key [sic] for the address to Bob. Now, Bob can use this private key for spending this money.

Wait a minute, how can Bob be sure that Alice isn't using his money before he is. Well, this is a non-problem. Even in the traditional bitcoin protocol Bob has to wait some time until the transaction is cleared. So, in this case, Bob just uses the money to move it to yet another bitcoin address and waits until this transaction clears out. So there is no difference in this regard, but there is an important advantage: An attacker can no longer make the assumption that one bitcoin address corresponds to one person. Now, let's make it even worse for the analyst: Every 2 hours alice generates a new bitcoin address and shuffles here money from her old addresses to her new addresses. One in a while she buys merchandise from Bob and in this case she just forwards Bob the current private keys and Bob continues this address shuffling.

So...just think of bit coins to be private keys to addresses and no longer money attached to addresses, Conceptually, this becomes a different world.

And, voila, bitcoin now is really anonymous.

Feedback?