This article, for the purpose of making the Rollup model easier to understand and analyze, Celestia researcher NashQ has divided the sequencer of Rollup into two logical entities - the aggregator and the header producer. At the same time, he divided the transaction ordering process into three logical steps: inclusion, ordering, and execution.
Guided by this analytical thinking, the six major important variants of Sovereign Rollup are clearer and easier to understand. NashQ has detailed discussions on the censorship resistance and liveness of different Rollup variants, and also explored the minimum configuration of each Rollup variant node in the state of minimal trust (that is, to achieve a Trustless state, at least what types of nodes Rollup users need to run).