HW2 - Wallet Seed to Ethereum Address

The Ethereum Wallet Pipeline

Click on each step to reveal the cryptographic processes and roles.

BIP-39

Mnemonic

→

BIP-32 / 44

Private Key

→

secp256k1

Public Key

→

Keccak-256

Raw Address

→

EIP-55

Checksum Address

1. Mnemonic Generation (BIP-39)

Concept: Key Generation & Encoding. High-entropy random data (128-256 bits) is generated and encoded into human-readable words (12-24 words) using a standard dictionary. This provides a user-friendly backup. The mnemonic is then converted into a 512-bit seed via PBKDF2 (key stretching).

Cryptographic Distinctions

Key Generation vs. Key Derivation

Generation (BIP-39): Creating raw entropy from a true random number generator. It happens once.
Derivation (BIP-32/44): Deterministically calculating mathematical child keys from a master parent key using hash functions. If you have the parent, you can always recover the children.

Hashing vs. Public-Key Crypto

Public-Key Crypto (secp256k1): Asymmetric cryptography. It works in pairs (Private/Public) and allows digital signatures. Reversing is hard due to ECDLP, but structured.
Hashing (Keccak-256): A one-way algorithmic grinder. Takes any input and destroys structure to produce a fixed-length output. Used to hide the public key.

Checksums vs. Encoding

Encoding changes the format of data for representation (e.g., Hexadecimal `0x` turns bits into readable characters). A Checksum (EIP-55) introduces redundancy to detect errors: it uses the Keccak hash of the address itself to capitalize certain letters, ensuring a typo immediately invalidates the address.

Temporal & Historical Context

1977 - RSA
Introduction of practical public-key cryptography (factoring large primes).

2001 - SHA-2 / SHA-512
NIST standardizes the SHA-2 family. Still widely used (Bitcoin uses SHA-256).

2012 - BIP-32
Hierarchical Deterministic (HD) wallets introduced for Bitcoin.

2013 - BIP-39
Mnemonic codes introduced, replacing raw hex backups with English words.

2014 - BIP-44
Standardized derivation paths (multi-coin, multi-account structures).

2015 - SHA-3 (NIST)
NIST officially standardizes SHA-3, based on the Keccak algorithm.

2016 - EIP-55
Vitalik Buterin proposes mixed-case Ethereum addresses for typo protection.

SHA-3 vs Keccak-256

While historically related, they are not identical.

Keccak won the NIST competition for the new hashing standard.
Before finalizing SHA-3 in 2015, NIST slightly changed the padding scheme (appending `0x06` instead of Keccak's original `0x01`).
Ethereum's development started before NIST finalized SHA-3, so Ethereum uses the original Keccak-256. Hashing the same input with SHA3-256 and Keccak-256 yields different results!

Why Multiple Techniques? (Separation of Concerns)

Why not use one algorithm? Because each step solves a different problem with specific statistical requirements:

BIP-39/32/44: Solves UX (User Experience). Humans can't memorize 256 bits, but can write down 12 words. Trees allow one backup for infinite accounts.
secp256k1: Solves Authentication. We need algebraic structure to prove ownership (signatures) without revealing the private key.
Keccak-256: Solves Quantum/Exposure risk. It destroys the algebraic structure of the public key, adding a layer of collision-resistant hiding.
EIP-55: Solves Human Error. Uses statistical probability (1 in 256 chance of accidental collision) to prevent sending funds to a typo'd address.