Two roles, one binary: node and validator. Nodes serve queries and propagate gossip. Validators do the same and additionally produce blocks while attesting custody.
Lower bar. Runs the binary, exposes the gateway surface, propagates blocks. Does not require hardware attestation in alpha. Onboard at /app/nodes.
Higher bar. Hardware attestation, key management discipline, synchronized time, observation period before joining quorum. Onboard at /app/validators.