As the âquantum threat,â a long-debated topic in the cryptocurrency world, once again takes center stage, a noteworthy development has emerged concerning a developer.
Independent developer Avihu Levy has published a study suggesting that Bitcoin transactions can be protected against quantum computers without making any changes to the current protocol.
This approach proposed by the developer requires neither a soft fork nor a network-wide consensus change. In this respect, it stands out as an alternative solution to the post-quantum updates that have been debated for a long time and which are said to take years.
Recently, the potential threats posed by quantum computers to cryptography have resurfaced. A study published by Google revealed that the thresholds for quantum processing capacity required to break Bitcoinâs cryptographic systems could be significantly lowered. This development reignited âQ-Dayâ scenarios, where quantum computers are expected to break existing encryption systems.
The Bitcoin network uses ECDSA (Elliptic Curve Digital Signature Algorithm) to secure transactions. However, theoretically, a sufficiently powerful quantum computer could break this system using Shorâs Algorithm and gain access to private keys from public keys. This poses a potential risk, especially for addresses that have previously processed transactions.
Current proposed solutions, such as post-quantum upgrades like BIP 360, require extensive network consensus and are therefore considered time-consuming processes to implement.
Avihu Levyâs proposed method completely moves security away from elliptic curves and towards a hash-based structure. The solution uses a signing approach based on the RIPEMD-160 algorithm, which has been used since Bitcoinâs inception. In this model, transactions are verified with one-time signatures generated from hash functions.
This approach also incorporates the HORS method, a hash-based one-time signature system. Based on the assumption that quantum computers will be ineffective at reversing hash functions, this system theoretically offers a robust structure against current quantum attacks.
According to experts, while quantum computers can target elliptic curves with the Shor algorithm, they can only use methods with more limited effectiveness against hash functions, such as Groverâs Algorithm. Although this lowers the security level, it still makes it extremely difficult to break in practice.
One of the most remarkable aspects of Levyâs solution is that it operates entirely within Bitcoinâs existing rules. The solution stays within the networkâs script limits (10,000 bytes and maximum opcode limits) without requiring a new opcode or protocol change.
However, the study is currently considered a âproof of concept.â The large transaction sizes make it difficult to deploy over a standard network, and costs are reported to range from $75 to $150 per transaction using cloud GPUs. Furthermore, it is stated that large-scale on-chain testing has not yet been conducted.
The development suggests Bitcoin may be more resilient to quantum threats than previously thought, sparking two differing viewpoints within the community. Some consider such scenarios âFUDâ (Fear, Uncertainty, and Doubt), while others argue that precautions should be taken against potential risks.
*This is not investment advice.