To gain access to the network's proof-of-stake transaction validation and security, blockchains can connect to Polkadot and operate in parallel as "parachains." The network's "relay chain" verifies transaction addresses and standardises data so that all systems can understand it. This is the location where all of the chains' security is centralised.

While functionality is handled, Polkadot-connected blockchains are free to use their own PoS method, choose when and how to upgrade their code, and run any apps or tokens they want. It is a selectable layer that allows networks to maintain security while incorporating new protocols.