Odaily Planet News: In a long post on the X platform, a16z Crypto pointed out that the timeline for the emergence of quantum computers capable of breaking cryptocurrencies (CRQCs) is often exaggerated, and the likelihood of such computers appearing before 2030 is extremely low. Different cryptographic primitives face varying levels of risk. Post-quantum cryptography needs to be deployed immediately due to the threat of "harvest now, decrypt later" (HNDL) attacks. In contrast, post-quantum signatures and zkSNARKs are less vulnerable to HNDL attacks. Premature migration to these technologies could introduce performance overhead, immature implementations, and code vulnerabilities, so a cautious rather than hasty migration strategy is recommended. For blockchains, most non-private public chains like Bitcoin and Ethereum primarily use digital signatures for transaction authorization, so they are not at risk from HNDL attacks. Their migration pressure mainly stems from non-technical challenges such as slow governance, social coordination, and technical logistics. Bitcoin faces specific issues, including its slow governance process and the existence of millions of quantum-vulnerable tokens worth tens of billions of dollars that may be abandoned. In contrast, privacy chains, which encrypt or hide transaction details, do face confidentiality risks from HNDL attacks and should transition as soon as possible.
a16z Crypto emphasized that in the coming years, implementation security issues such as code vulnerabilities, side-channel attacks, and fault-injection attacks pose more immediate and significant security risks compared to the distant threat of quantum computers. Developers should prioritize investments in code audits, fuzz testing, and formal verification.