Enshrined/Non-Enshrined

Definition of Enshrined
  • If a rollup chain posts its blocks and proofs to a settlement layer that acts as a settlement hub such as Ethereum, we say that the settlement layer is enshrined if the canonical chain and its transaction validity rules are determined by the settlement layer.
Definition of Non-Enshrined
  • On the other hand, if the rollup posts its blocks and proofs to a settlement layer but the canonical chain of the rollup is ultimately decided by the rollup network itself, we say that the settlement layer is non-enshrined. In order for a non-enshrined settlement layer to make sense, it should have a way to upgrade the rollup that does not require hard forking the settlement layer.