Buterin’s upgrade proposal would only apply to private keys to wallet addresses. The main objective of the upgrade is to increase the resistance to collisions.
Ethereum creator Vitalik Buterin recently published a proposal to improve the security of Ethereum wallet addresses. To do this, he proposes to increase their size from 20 to 32 bytes.
The purpose is to increase “the resistance to collisions that the hashes of public addresses have.” In other words, it seeks to prevent two different private keys from accessing the same public address.
The proposal that Buterin published would only apply to EOA private keys, which correspond to wallet addresses. This suggestion would not involve smart contracts, which would continue to use 20-byte addresses. However, it establishes the creation of a “translation table” (or algorithm) to compress and decompress new 32-byte addresses. That way, they will be able to work seamlessly with smart contracts.
Collision Resistance or “the Possible of the Impossible”
It is important to remember that a hash is a basic algorithm that has an input and an output in a single format. If the input has a minimal change, the output will be totally different.
Collision resistance refers to the impossibility of two different inputs generating the same output. Although it seems impossible, it is mathematically possible that it exists, that is, two different private keys could access the same public address.
Currently, the collision resistance of Ethereum addresses is 2^80. This indicates a low probability of creating two different inputs for the same output. In more visual terms, the value of 2^80 is a 1 plus another 32 digits.
The new update will increase the impossibility of having two different keys for the same address up to 2^160. The Bitcoin network currently has a collision resistance of 2^90, which makes it very resistant to collisions.
Although it is a present dilemma, vulnerability to such an attack requires the attacker to have very advanced cryptographic knowledge. Besides, he or she must have a supercomputer that allows executing a large number of iterations, until finding the corresponding hash entries.
Protection against Quantum Computing
A user inquired that Vitalik’s upgrade proposal should go hand in hand with protection against quantum computing. A potential surprise from quantum computing would involve an exponential growth in current computing power. That would break the private keys of cryptocurrencies, in addition to the cryptography of the Internet as people know it.
Responding to the user, Vitalik asserted that addresses of even 26 bytes are enough for the post-quantum era. If they do not accept 32-byte addresses, the Ethereum co-founder leaves open the alternative of using a 20-byte scheme.
Their use would have a divided format: 15 bytes for the address scheme and the remaining 5 to set identification. That would allow validating that the owner of the address is a single private key. The identifier would be the same set in the proposed 32-byte addresses.
By Alexander Salazar
