The prospect of quantum threats has put pressure on major networks such as Ethereum and state systems alike to re-evaluate their security posture. According to Dmitry Khavratovich of the Ethereum Foundation, blockchain is not without its obstacles in this regard. In a piece for Forklog, the researcher noted that whereas the US has moved ahead with post-quantum cryptography for its government systems, the challenges are quite distinct for a blockchain network.
US Takes the Lead in Post-Quantum Migration
Dmitry Khavratovich has noted on Forklog that the U.S. is in the process of shifting its government operations over to post-quantum cryptography standards. It is a preemptive measure against the prospect of quantum computers rendering conventional cryptographic algorithms obsolete. But as Khavratovich observes, one cannot expect the same top-down approach to work with blockchain networks. Government bodies have the authority to impose such changes, yet these decentralized systems are subject to other limitations; any move to revise encryption protocols requires agreement from a large and independent pool of participants.
Why Blockchain Networks Struggle with Upgrades
For blockchain ecosystems, the move to post-quantum standards is anything but a simple matter. It is not uncommon to find platforms, some of them on older infrastructure, relying on cryptographic algorithms that date back to the 1980s. Khavratovich points out that updating such systems requires a great deal of time and coordination. The stakes are real as well. A quantum computer of sufficient power could use Shor’s algorithm to extract private keys from public ones, which would put billions in value at risk, even the wallets of the likes of Satoshi Nakamoto.
Scaling Challenges and Potential Solutions
There are fresh complications in the move to post-quantum digital signatures. Khavratovich has pointed out that, being much larger than what is in use today, they have the potential to slow down blockchain throughput and drive up the cost of transactions. In a way, this scalability issue only serves to complicate the quantum threat to the blockchain further. To counter it, some developers are looking at zero-knowledge proofs as a means of lightening the load on the base layer and preserving network efficiency.
How pressing these adjustments are is really a matter of when quantum computers will be ready. A sudden appearance of a capable machine would make the replacement of every cryptographic key an urgent priority. Then again, one could take Khavratovich’s more cynical view: should the hardware never come to pass, there would be no problem to speak of.
Source — forklog: https://www.youtube.com/watch?v=2aUq9V1EDXM