Substate Model

Overview

The Substate Model is Radix's approach to storing and managing on-ledger state. Rather than using a global account-based model (Ethereum) or UTXOs (Bitcoin), Radix breaks state into fine-grained pieces called substates.

Each substate is an independently addressable, independently lockable piece of data. A component's state might consist of dozens of substates — each vault, each metadata field, each access rule is its own substate.

Why It Matters

This granularity is what enables Cerberus to achieve unlimited parallelism. Two transactions that touch different substates can execute on different shards simultaneously, even if they interact with the same component. Only transactions that touch overlapping substates need coordination.

Compare this to Ethereum's account model: any two transactions interacting with the same contract must be serialized, even if they access completely different data within that contract. This creates bottlenecks around popular contracts (DEXes, stablecoins).