The potential for quantum computing to infiltrate current cryptographic systems continues to generate debate among analysts, researchers, and users.
In that sense, Bitcoin developer and member of the Frostsnap hardware wallet team, known as LLFOURN at X, joined the discussion at X.
His position is straightforward:
Ethereum has much bigger problems with quantum than Bitcoin.
LLFOURN, Bitcoin developer.
The statement refers to Structural differences between both networks We also discuss how cryptography supports critical functions such as consensus security, signature verification, and funds storage.
IBM quantum developer Steve Tippeconnic echoed similar sentiments, telling CriptoNoticias: Ethereum Face a wider attack surface:
At a macro level, Ethereum’s architecture is more complex, with smart contracts, multiple signature schemes, and a larger cryptographic footprint. This means it may need to upgrade more components than Bitcoin in the post-quantum era.
Steve Tipeconic.
Why Ethereum will be more vulnerable to quantum than Bitcoin
LLFOURN supported three central arguments.
First of all, he pointed out that Ethereum’s consensus mechanism based on Proof of Stake (PoS) relies on ECDLP (Discrete Logarithm on Elliptic Curve). Encryption formats vulnerable to quantum computing and algorithms shawl.
In the developer’s words:
Since Ethereum’s consensus relies on ECDLP, the consensus itself can be broken by quantum computers.
LLFOURN, Bitcoin developer.
Bitcoin also uses elliptic curve algorithms, specifically an algorithm known as ECDSA (Elliptic Curve-Based Digital Signature Algorithm).
However, the difference between both networks lies in where these weak ciphers (ECDLP and ECDSA) operate in each network. In Bitcoin, the ECDSA scheme is only used for signing transactions. but does not participate in the consensus mechanism Like in the case of Ethereum.
Therefore, in Bitcoin, an eventual quantum break could result in funds whose public keys are already known to be compromised (addresses reused); It does not affect block validation or consensus operations.
Proof of Work (PoW), the consensus mechanism used in Bitcoin, relies on the SHA-256 algorithm, which is more quantum-resistant (it is only vulnerable to the much slower Grover attack). Furthermore, automatically adjusting the mining difficulty reduces the actions of quantum attackers.
In this scenario, the network created by Satoshi Nakamoto soft fork (change only signature scheme and address format), There is no need to rewrite the consensus structure.
Impact on Ethereum consensus: potential quantum risks
If a quantum computer were able to crack the cryptographic signatures that underpin Ethereum consensus, the implications would reach to the heart of the protocol.
An attacker who can generate signatures at the consensus level without knowing the private key Can impersonate a validator and cast fake votes to disrupt the process This allows the network to define which blocks are valid.
The ability to sign on behalf of genuine validators allows attackers to influence consensus voting, introduce fraudulent blocks, and even Reorganize the chain if enough signatures can be forged.
The risk does not come from the loss of funds, but from the possibility of directly manipulating the machinery that maintains the integrity of the chain.
In that sense, Tippeconic has demonstrated that: Bitcoin’s risk to quantum is realhighlighted the fragility of Ethereum’s consensus, but his view is more cautious.
Both ecosystems face challenges, and both need to prepare for a quantum future. It remains to be seen what the optimal migration path will be.
Steve Tipeconic.
Ethereum Virtual Machine (EVM) is another weak link in the network.
The second point developer LLFOURN makes is about the Ethereum Virtual Machine (EVM), stating that “Ethereum never built standard ECDSA signature verification[into the EVM].”
Please use instead ecle covera function that allows you to restore an address from a signature. Difficult to transition to quantum-resistant schemesaccording to LLFOURN.
This Bitcoiner developer thinks similar to what Tippeconnick said: Ethereum has more complex fields To defend against quantum attacks:
Post-quantum signature schemes cannot be directly replaced. All smart contracts that use ecrecover must be rewritten.
LLFOURN, Bitcoin developer.
That means, miles of contract Deployed ones must be changed manuallycan be slow and complicated.
More public transaction keys may be exposed on Ethereum
The third point deals with publishing the public key. Although LLFOURN did not provide specific data, he emphasized that:
This is a strength in favor of Bitcoin over Ethereum, as the majority of Ether on Ethereum is in addresses where the public keys are exposed.
LLFOURN, Bitcoin developer.
If the public key has already been published, Quantum computer can derive private key and steal related funds.
According to that analysis, Bitcoin has a small percentage of coins that are under addresses that reveal their public keys only when used. Reduce attack surface area.
Still, as CriptoNoticias previously reported, there are approximately 7 million BTC held by exchanges at risk of being stolen by quantum attackers due to address reuse.
Finally, LLFOURN concluded the discussion by pointing out that even in a scenario where there is a “slow quantum” phase (a period in which quantum computers are dangerous but not yet powerful enough), Ethereum will not be in an advantageous position.