Look for Deezeyay's excellent explanation on how things will get hacked with the key address... It was scary to know that even after hard fork during the coin swap with the old key address things will get exposed
As to other already existing cryptocurrencies forking into quantum proof crypto, there is a huge problem that's worth mentioning: even if they successfully fork their blockchain into a quantum proof crypto, their old coins can still be hacked as if they where not protected by quantum proof cryptography. Here's why:
Whether you hard-fork like BTC and end up with 2 coins like BTC and BCH or whether you hard-fork like ETH where you end up with 1 coin: after the fork, your coins or coin will be where you had your old coin: in a wallet or an exchange. This means it’s still accessible through your old private key. This old private key is NOT quantum proof, that's simply how forking works, you can't just make the old private key disappear. If the new coin wouldn’t be connected with the old private key, how would it end up in your wallet/ exchange and be accessible for you? So to finalize the quantum proof update, you will need to move your quantum proof coin to another wallet. That way you leave the old private key behind you with the old wallet. Your coins in your new wallet will only be accessible with your new quantum proof private key. Simple right? Guess what:
- Not everybody will do that. That’s just human nature. (People don't read, or read half, don't understand, postpone, don't care, don't know how or don't see the poin in any other way)
- There are a lot of coins lost or unaccessible because people lost their password or got locked out in another way. It happens a lot. So especially with coins that exist for a while like BTC and ETH, there are a lot of coins that nobody even CAN move to a new wallet. All these coins will still be accessable through the old private key after "quantum proving" the blockchain.
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So lots of new quantum proof coins, will not be moved away from the old private key and be accessible through both their old private key and their new quantum proof private key. It’s like when your house has a cardboard front door anybody can walk through. And to fix that, your make an new unbreakable door and install that as your backdoor, while leaving your front door as it was. As long as you don’t build a brick wall where your cardboard door is, people can still walk in your house and steal your stuff.
Thank you for this explanation. I was wondering about Quantum resistance is something that could be developed for existing Blockchains through forks. As I understand it you say that it could be possible?! Then the market for QRL might be a bit diminished since it is going to be hard to replace brand names sush as BitCoin.
The best thing for QRL would be proof of concept of that a quantum computer can break BitCoin encryption before they even lifted this as a risk. Since then people will panic and look somewhere else. It is for this that QRL will need a strong brand name to get people to flock to it.
No, you don't get it. I did not say it can be done. The question if a blockchain can be made quantum proof by forking is a different discussion, but is not relevant. Why? Because it would be useless even if it COULD be done. The point is this, and I will try to explain again below:
ALL existing crypto with coins or tokens out (ERC20 or the final product), can NEVER quantum-secure all their existing coins/ tokens and will therefore be at risk of having coins hacked and mass sold when quantum computers are in full function.
So let me rephrase that for clarity: even if they could upgrade their blockchain to a quantum secure blockchain, they can’t automatically secure the coins people own.
These coins can still be hacked after a quantum proof update.I’ll try to explain again but I’ll have to start at the beginning, so don’t blame me if it sounds basic:
A crypto has coins (or tokens). These coins are stored in wallets or on an exchange. As an owner of these coins, you want to be the only one to be able to access the coins and move them if you wish. So to protect your property, your coins are stored on an address: your public key. Your private key gives you the authorization to move them to another address (on an exchange it’s different because you don’t have the private key there yourself, but the result is the same: if someone cracks the main private key, they can steal your coins). Your public key can be known by others and is public, but your private key obviously not. If anybody gets your private key, they can get access and steal your coins.
Now how do you get these public and private keys? If you get a public key (address), the blockchain gives you the private key that comes with that public key. If you lose the private key, you will be locked out of the public key (the address) and you will never be able to get your coins out of there ever again. Blockchains can’t just email you a new private key, because the only way a blockchain knows you’re the owner, is if you show the private key. So if you lose it, you can’t prove anything, and your locked out for good. That is why blockchains are so secure.
So the only access to your coins that are stored on your public key, is through your private key. Private keys can not be hacked by normal computers. But quantum computers can hack the normal private keys. Now if a blockchain is quantum proof, they give you a public key with a quantum proof private key. So this private key can not be hacked by a quantum computer, and your coins are safe in that case. Now you think “ok, so if a blockchain upgrades to a quantum proof blockchain, the problem is solved”. But the problem is, if a blockchain already exists, there are millions of coins out there that NEED to be accessible by their owners after the fork or upgrade.
To understand why that is a problem, and why that can’t be solved, we need to understand how a fork works: so how can a blockchain be upgraded and still give the owners of the coins access to their coins.
After the fork, everybody needs to have the exact same amount of coins they had before the fork. So there will be a 1:1 tokenswap. Everyone who owns an amount of tokens of the old blockchain, will own that same amount of tokens of the new blockchain. To accomplish that, you will NEED to keep the old private keys active until the owner moves it’s coins to a new address: a public key that is accessible only through a new quantum proof private key. (Maybe another option would be that you wouldn’t need to move your coins to a new address, but the old private key would be de-activated after you claimed your new quantum proof private key. I don’t know if this last option is even possible, but if it would be possible, it would still mean that your old private key needs to be active after the fork until the owner uses it and actively de-activates it.)
So:
- The blockchain "knows" the amount of tokens you have at that specific time, and thus the amount of tokens you are entitled to, by looking at your public key. (Like for example etherscan does.)
- They can only send these tokens to its rightful owner, by sending them to that exact public key (address). That way it is guaranteed that only the rightful owner can access them, because only he has access to that address (The old private key and old public key). So then the new coins are on you old address, that is still accessible through your old private key. Now, even if it would technically possible, the blockchain can't erase the old private key or replace it with a new one, because then the owner would not be able to access his coins. Remember: he doesn’t HAVE the new private key. It’s not like you can get your new private key by email. So the blockchain needs to allow you to enter with your old private key, even if they just upgraded itself to a quantum proof blockchain. So your coins are NOT protected by that blockchains new and improved quantum proof private keys. Not until you have accessed your coins through your old private key. Then you would need to move them, or de-activate the old private key to lock your coins up in a way that it’s only accessible with a quantum proof private key.
So what you need to understand is this: after a blockchain is upgraded to a quantum secure blockchain, ALL coins are still accessible through the old private keys, and therefore still hackable by quantum computers.
So even though this blockchain can claim to be quantum proof, their coins are NOT until the owner accesses them and takes action. Now we come to the next point I wrote before, where you will see why a big amount of the coins of an upgraded blockchain will never become quantum secure:
- Not all owners of coins will take the necessary action. That’s just human nature. (People don't read, or read half, don't understand, postpone, don't care, don't know how or don't see the point in any other way)
- There are a lot of coins without an actual active owner: the owners lost their private key, their password or got locked out in another way. It happens a lot. So especially with coins that exist for a while like BTC and ETH, there are a lot of coins that nobody even CAN move to a new wallet. Don’t underestimate the total amount of these coins. All these coins will still be accessible through the old private key after "quantum proving" the blockchain because the owners need to move them, or de-activate the old private key to lock your coins up with a quantum proof private key.
So lots of new quantum proof coins, will not be moved away from the old private key and be accessible through both their old private key and their new quantum proof private key. It’s like when your house has a cardboard front door anybody can walk through. And to fix that, your make an new unbreakable door and install that as your backdoor, while leaving your front door as it was. As long as you don’t build a brick wall where your cardboard door is, people can still walk in your house and steal your stuff.
So the only conclusion can be:
Even if you could upgrade an existing blockchain to a quantum proof blockchain (and wether or not that is possible is still open for discussion), then still, a big part of their circulating supply can be hacked. Is that a problem? Yes, even if you move and secure your own coins, if others are stolen and sold, your coins will drop in value dramatically, and panic sales would be all around.