Definition
A settlement layer is a foundational blockchain system component where finalized state, transaction results, and proofs from upper layers are recorded and economically secured. It provides canonical ordering of transactions, enforces consensus rules, and anchors cryptographic commitments from scaling layers. The settlement layer typically hosts the base asset used for fee payment and economic finality, serving as the authoritative source of truth for state transitions.
In Simple Terms
A settlement layer is the base blockchain where final records of transactions and state are stored and protected. Other connected layers rely on it to lock in their results, using its consensus and security so that all participants agree on a single, official version of what has happened on the network.
Context and Usage
The term “settlement layer” is commonly used in discussions of modular blockchain architectures and scaling designs. It appears in analyses of how Layer 1 systems interact with Rollup environments, how Data Availability is organized, and how finality is defined at the level of a Block. It is central to debates about security guarantees, economic finality, and the division of responsibilities across different protocol layers.