Here is a comprehensive article on Ethereum and its use of Bitcoin addresses instead of public keys:
Why use Bitcoin addresses instead of public keys in Ethereum?
Ethereum, one of the most popular blockchain platforms, uses Bitcoin addresses instead of public keys to manage transactions. While public keys are commonly used in cryptographic systems such as RSA and Elliptic Curve Cryptography (ECC), they have their limitations when it comes to secure communications and digital signatures. In this article, we will explore why Ethereum chose to use Bitcoin addresses and the benefits of doing so.
Why hash the public key twice?
In traditional public key cryptography, a public key is used to encrypt a message, and the encrypted message is then hashed (or digitally signed) before it is sent or stored. This process ensures that only the intended recipient can decrypt the message. However, when using Bitcoin addresses in Ethereum, the process is a little different.
To hash the public key twice, we need to perform two cryptographic steps:
- Hash the public key: The Bitcoin address is hashed using a one-way function such as SHA-256. This creates a fixed-size string of bytes called a “hash” or “message digest.”
- Sign with a private key: The hash created in step 1 is then encrypted (or digitally signed) with the corresponding private key of the Bitcoin address owner. This creates a new message that contains both the hash and the signature.
Security benefits
Using Bitcoin addresses instead of public keys provides several security benefits:
- Uniqueness: Each Bitcoin address has a unique identifier, making it difficult to guess or duplicate addresses.
- Non-repudiation: By using a private key to sign messages, Ethereum ensures that the sender cannot deny sending the message. This is called non-repudiation.
- Double-spending prevention
: With Bitcoin addresses, it is much harder for an attacker to spend the same Bitcoin twice.
Does public key abstraction provide more security?
Public key abstraction can provide some security benefits:
- Reduced vulnerability: By using a single identifier (Bitcoin address), we reduce the number of potential vulnerabilities.
- Improved scalability: With fewer addresses, it is easier to scale the network and handle more transactions.
However, public key abstraction also has its drawbacks. For example:
- Increased complexity: Managing multiple Bitcoin addresses can be complex and error-prone.
- Difficulty in recovering lost data: If a private key is lost or compromised, it can become difficult to recover all associated assets (i.e. Bitcoin).
Representations of multiple things
Bitcoin addresses are designed to represent multiple things:
- Unique identifiers: Each address has a unique identifier (a 64-character string).
- Transaction data: Addresses can contain additional information about the transaction, such as the sender’s or recipient’s public key.
By using Bitcoin addresses, Ethereum enables more efficient and flexible digital signatures. The security benefits of a public key abstraction are significant, but it is important to weigh these benefits against potential drawbacks when designing a cryptographic system.
Conclusion
Ethereum’s use of Bitcoin addresses instead of public keys is a deliberate design choice that provides several security benefits. While there are some drawbacks to consider, in many cases the benefits outweigh the drawbacks. As more users and developers experiment with Ethereum, we can expect its cryptographic architecture to evolve and improve over time.
I hope this article helped clarify why you should use Bitcoin addresses instead of public keys in your Ethereum wallet!