The Protocol State maintains state about the operation of the Flow network protocol, including the identity table and resources produced by nodes in the Flow network: blocks, collections, receipts, approvals, seals, etc. The protocol state is used by the software that runs the Flow network.

Further Reading

Protocol Violations and Slashing

Identity-Changing Operations

Epochs and 👉 Epoch-Aware Protocol State

Dynamic Protocol State - Software Design

Proposed change to error handling: https://github.com/dapperlabs/flow-go/issues/6368