Primary Chain

Definition ∞ A Primary Chain refers to the main or foundational blockchain within a multi-chain or layered network architecture. This chain is typically responsible for core security, data availability, or final settlement functions for the entire ecosystem. It serves as the base layer upon which other, often more specialized, chains or layers are built. Its robustness is paramount for the overall network.
Context ∞ In many scalable blockchain designs, secondary chains or layer-2 solutions derive their security from a primary chain, such as Ethereum’s role for numerous rollups. The performance, security, and upgradeability of the primary chain directly impact the entire ecosystem built upon it. Discussions often focus on the trade-offs between decentralization, security, and scalability at this foundational level of the network architecture.