[tczMUFlmoNk]

> public key of a wallet (present on any outgoing transaction in the ledger)

Genuine question: is this true? I only know a little bit about Bitcoin, but I thought there was a notion of an "extended public key" that's not exposed to the ledger, where each individual public key on the ledger is only used once, or something like that.

I'm not at all confident in my understanding, so I'd love if you or someone else knowledgeable could help fill in the gaps.

[johncolanduoni]

Extended public keys can be used to generate a family of addresses, but each transaction still needs the public key for any address that has sent money. Someone who uses it religiously can keep most of their money in addresses with no outgoing transactions, meaning their public key is actually secret and therefore cannot be attacked. But there’s so many addresses that have outgoing transactions and huge balances that it wouldn’t make a difference to an attacker - they could skim a fortune and cash out from wallets that are not so well protected.

[andy_ppp]

The real issue is as soon as this is done once Bitcoin's value plummets to a fraction of what it was today while people scramble to fix the algorithms.

[tczMUFlmoNk]

Thanks for explaining!