3 ms·
No one has a single "permanent" Bitcoin address. A Bitcoin address is just an identifier (cryptographic hash) of a public key in a keypair. For every transacti
by lambda 12y ago
No one has a single "permanent" Bitcoin address.
A Bitcoin address is just an identifier (cryptographic hash) of a public key in a keypair. For every transaction you do, you can create a new one. It's also possible to publish one publicly, as an address to anonymously send donations to, which can also make it easier for the public to track how many donations have gone to that address, but for most purposes, you create one per transaction, so you can keep track of how much has been spent in that transaction.
Any time you send Bitcoins, the way it works is that it sends the portion you specify to the given address, and generates a new keypair for yourself to send the change back to an address you control.
So, unless you just happen to leave a single address published publicly as your donation address, you don't have a permanent address. If you want to collect any additional information associated with a transaction; an email address to send thanks (or hit up for donations later), information to collect for tax purposes, etc, you just create a new keypair and thus new address for that transaction.
- butwhy 12y agoYou just contradicted yourself, which is misleading. You started off by saying: > No one has a single "permanent" Bitcoin address. And then you finished with: >So, unless you just happen to leave a single address published publicly as your donation address, you don't have a permanent address.
- lambda 12y agoSo yes, you can arbitrarily pick one address of yours to share publicly and keep permanent. But there is nothing in the protocol or any of the default clients that gives anyone a distinguished "permanent address". So saying "I wish we knew Mozilla's permanent Bitcoin address" indicates that such a thing is expected, when in reality any one address that an entity has is a good as any other, and addresses are generally intended to be ephemeral and single use.
- jb55 12y agoI have a single, permanent Bitcoin address (1jb55g498MEa274Z1YWUXQFxZE5NzvhV7). I don't pretend Bitcoin is anonymous and I always set my change address to go back to the inputs. I understand the risks of how the address inputs and outputs as probabilistically tied to my identity. If I cared about those things I probably use stealth addresses and dark wallet or something.
- modeless 12y agoThere are also cryptographic risks associated with reusing an address, not just identity risks. The address is a hash of your public key. You don't have to reveal the public key matching the address until you spend from the address. When the public key is secret, your address is safe even from hypothetical attacks on Bitcoin's crypto implementation. Once you spend from the address, the public key is public knowledge and that extra protection is lost. https://en.bitcoin.it/wiki/Address_reuse https://en.bitcoin.it/wiki/Address_reuse
- jb55 12y agoI think if someone can hack my wallet from a public key we have bigger problems
- lambda 12y agoSo, that "single permanent address" can work fine if you're just looking for donations, or doing transactions with people you trust. If you're doing any kind of transactions in volume, it's much easier to just give each customer a unique address to send to, so you can verify that you've been paid when the right amount has been transferred to that address. That way you don't have any confusion of who has actually paid you if two people owe you similar amounts at the same time, and you see a transaction come in of that amount. So yes, it's possible to pick one address as your "single permanent address", but it's not something that's expected or common.