A report published by the a16z crypto developer group questioned the urgency raised by some in the crypto ecosystem regarding an immediate transition to post-quantum cryptography.
According to the report, “Timeline for realization of quantum computers related to cryptography” “They are often exaggerated.”leading to “calls for urgent and widespread relocation.”
As shown in the document published on January 24, all of these requests do not always take into account important items such as:
- Implementation risks.
- Fundamental differences between different types of cryptographic primitives.
As Criptonoticias reports, these differences between analysts mean that the relationship between Bitcoin and quantum computing is between reality and FUD. This situation makes it necessary to analyze whether the potential dangers presented by this technology will affect the price of the currency.
What quantum means (and doesn’t mean) for Bitcoin
In the case of the a16z crypto, quantum threats to Bitcoin will not manifest as a sudden collapse, but as a “selective and gradual process.”
Shor’s (quantum) algorithm could theoretically break the elliptic curve cryptography used in Bitcoin, called ECDSA. that’s this Secure the digital signature of your transactions.
As detailed in the a16z report, that quantum algorithm must be applied on a per-key basis. The process of The first attack is “very costly and time consuming”.
The report also reveals: Most users are relatively protected. “Without changing protocols right away.”
who Prevent address reusedoes not use output that directly exposes the public key, and protects the funds behind a hash function. In such cases, the risk only arises when the funds are used.
However, currently approximately 7 million Bitcoins (BTC) will be vulnerable to quantumas reported on the Project Eleven site earlier this month, is due to address reuse.
Bitcoin’s weakest point against quantum computers
The a16z crypto report takes this vulnerability into account. Note that the biggest problem is represented by potentially abandoned coins whose public keys are already public. “Some estimates say these Bitcoins could be in the millions.” This poses major technical, economic, and legal dilemmas.
document mentions theoretical options: Declare those coins burnt or leave them open to claim. However, it warns that this last option “raises significant legal and safety issues”.
Adding to this problem of abandoned coins are the limitations of Bitcoin itself, including slow governance, low transaction capacity, and the inability to passively migrate.
In the words of the report: “Time pressures do not come from an impending quantum computer; But it’s about the social and technical logistics of coordinating the transition. ”.
“Quantum risk is overstated”
The report highlights that one of the main mistakes in the current debate is that it deals with all cryptography. as a homogeneous block.
Not all cryptographic tools perform the same functions or are exposed to the same level of quantum computing.
a16z crypto report.
Developers warn that applying a blanket sense of urgency will skew risk analysis.
In particular, the document Distinguish between encryption used to protect the confidentiality of information. and digital signature. These work to authenticate messages and authorize transactions, much like what happens with Bitcoin and Ethereum.
Both components (encryption and signing) will react very differently to the eventual arrival of a functioning quantum computer.
Differences between encryption, signatures, and keys
practice «“Harvest now, decrypt later” (HNDL, or collect now and decrypt later) they are already underway«, says the report. This refers to an adversary storing currently encrypted communications in order to decrypt them in the future, when sufficiently powerful quantum computers exist.
So for a16z cipher, “Post-quantum encryption requires immediate adoption.”. Even after assuming cost overruns and implementation risks. On the other hand, “digital signatures face a different calculation. Immune to HNDL attacks. ”.
This is because it contains no secrets that can be retroactively deciphered. If a signature was created before the associated quantum computer existed, it cannot be considered false after the fact.
As the document explains, both Bitcoin and Ethereum “use non-quantum cryptography primarily for transaction authentication, rather than encryption.” this The immediate urgency associated with HNDL is removed.
true quantum horizon
The study also defines exactly what it means to: Cryptography-related quantum computers (CRQC): A fault-tolerant error-correcting machine that can run Scholl’s algorithm at a scale large enough to defeat schemes such as ECDSA and RSA-2048 in a reasonable time frame.
It is highly unlikely that CRQC will materialize in the 2020s.
a16z crypto report.
That’s why from a16z crypto They have doubts about corporate advertising. About “quantum supremacy” or “thousands of logical qubits.” They warn that “raw qubit counts are misleading.” Without persistent error correction, such systems are useless for cryptanalysis.
To summarize, we expect to see machines capable of breaking ECDSA or RSA-2048 in the next five years. “Not supported by publicly known progress”And 10 years from now, he will still be “ambitious.”
In conclusion, the biggest immediate risks to blockchain are: it’s not quantumbut is operational. “Implementation vulnerabilities will be a much bigger threat than CRQC for years to come.”
(Tag translation) Bitcoin (BTC)
