Understanding the Input Size for P2PKH Transactions on Ethereum
Ethereum’s public-key-based cryptocurrency, P2PKH (Pretty Good Privacy), allows users to make secure transactions without revealing their private keys. However, the input size of P2PKH transactions can be an area of confusion for both novice and experienced developers.
Input Size: What Does It Mean?
The input size of a P2PKH transaction refers to the length or number of bytes of input data used in the transaction. This information is crucial in determining whether a specific input size is viable or not.
Default Miner Implementation: Pay-to-Pubkey
To understand why the default Ethereum miner implementation uses pay-to-pubkey, we need to delve into the details of how transactions are processed and verified on the network.
A P2PKH transaction consists of two inputs:
- Send Amount: Input amount used in the transaction (in bytes).
- Signature: A cryptographic signature (using the private key) that proves the sender’s identity and control over the associated public key.
The miner implementation uses push + sig + push + key = 1 + 72 + 1 + 61, which translates to:
- Push Amount: 1 byte
- Signature Length: 72 bytes (assuming SHA-256-based hash function)
- Public Key Length: 61 bytes (again assuming SHA-256-based hash function)
Why Pay to Publish?
Using a public key for payment allows the miner implementation to efficiently verify and process transactions. Here’s why:
- Hash Function
: The SHA-256 hash function is used to create a unique input value, which is then signed by the sender.
- Verification: The signature verifies the identity of the sender, ensuring that the public key associated with the transaction is in fact controlled by the sender.
What about the default miner implementation?
The default miner implementation uses pay-to-pubkey because it allows for efficient and scalable transaction processing. By using a single input value (push + sig), a miner can verify the signature and extract the public key in a single operation, reducing computational overhead.
Application
In summary, understanding the input size of P2PKH transactions is essential for designing and implementing secure and efficient Ethereum nodes. The default miner implementation uses pay-to-public-key to optimize processing efficiency, which can lead to different input sizes depending on the specific use case or implementation variant used.
Please note that this information is subject to change as new versions of Ethereum are released, and updated implementations may alter miner behavior. For developers and users looking to build secure and scalable nodes, staying up to date with the latest developments is crucial to ensuring optimal performance and security on the Ethereum network.
