Could you describe how such a cross over could happen smoothly? Seems like there would be mass panic, all the mining rigs would have to re assemble etc.
Announce a transition time a few years into the future so the miners don't get a capital loss.
Code clients to switch over to the new algorithm at the transition time. When the transition finally comes, even those with slightly out of date client will switch over, since it was coded far in advance.
Re:Quantum Attack on Public-Key Algorithm
by glomph on Saturday December 06, 2014 @03:37PM
(#8710111)
Wouldn't this require quantum computing to be developed relatively gradually and in the open? Seems likely that a gov or company will suddenly reveal it or have it exposed.
Sudden, catastrophic leak of an operational QC would definitely be a cryptogeddon scenario.
Not really, because bitcoin only relies on the signature aspect of PKC. So, bitcoin could move over to Lamport signatures, which are not affected by quantum computing.
Lamport signatures are larger than ECDSA signatures, so blockchain bloat would be an issue. But presumably by then hard drives and all other computing specs would have increased substantially.
Here's an interesting article by Vitalik Buterin which explains how the transition could take place: http://bitcoinmagazine.com/6021/bitcoin-is-not-quantum-safe-...