How Does the “Proposer-Builder Separation” (PBS) Model Enhance Security?

The Proposer-Builder Separation (PBS) model enhances security by decentralizing the power of MEV extraction. By separating the block creation (builder) and block proposal (proposer/validator) roles, it prevents the validator from unilaterally executing all MEV and censoring transactions.

The builder competes to create the most valuable block, which is then submitted privately to the proposer. This competition reduces the centralization risk associated with a single validator having complete control over transaction ordering and inclusion, thereby enhancing the chain's censorship resistance and fairness.