The Internet Computer blockchain is created by nodes in data centers located around the world that are running the Internet Computer Protocol (ICP), providing a secure and reliable way to run Canister smart contracts. To make the Internet Computer scalable, we increase the capacity by adding subnets (aka blockchains), where groups of Canisters run together. Canisters get security and reliability through an approach called replication. Replication enables nodes on the Internet Computer blockchain to resume and catch up to the latest state of the protocol.