Session 02
Protocol Level

ETHEREUM
ARCHITECTURE.

A deep technical exploration of Ethereum’s network design, execution model, gas economics, and state management.

Objective

Deconstruct the Ethereum stack: understanding how nodes maintain global state via peer-to-peer communication, the deterministic nature of the EVM, and how gas fees regulate computational resources.

01

The Network Layer

Ethereum operates as a peer-to-peer network of nodes. Unlike client-server architectures, every full node stores the complete history and state of the blockchain.

  • Execution Clients (Geth, Nethermind)
  • Consensus Clients (Prysm, Lighthouse)
  • P2P Communication (devp2p)
FIG 1.0

Block Propagation & State Sync

02

Ethereum Virtual Machine (EVM)

The EVM is a quasi-Turing-complete state machine. It is stack-based, meaning it operates on a Last-In-First-Out basis with a word size of 256 bits to facilitate native hashing and elliptic curve operations.

Stack Architecture

256-bit word size. 1024 item depth limit. Strictly deterministic.

Isolated Sandbox

Code runs with no access to network, filesystem, or other processes.

Global State

A large data structure (Merkle Patricia Trie) holding all accounts.

Bytecode Execution

High-level Solidity compiles down to low-level Opcodes.

03

Gas & Economics

Gas is the unit that measures the amount of computational effort required to execute operations. It serves two purposes: preventing infinite loops (Halting Problem) and prioritizing market resources.

Total Fee = (Base Fee + Priority Fee) × Gas Used

01User signs transaction
02Tx broadcast to Mempool
03Validator bundles Tx into Block
04EVM executes & state updates

System Check

State relies on Account Model, not UTXO

EVM guarantees deterministic execution

Gas aligns computation with cost