[toufka]

Are rollups generally expected to be 'native' to etherium, or orthogonal - but packaged in a way that becomes well-integrated with L1? Or said another way, it seems like there are L2 rollup 'providers' - are these 3rd party providers inherent in an L2 solution, or are they features that will be subsumed later by the parent protocol?

[chrisco255]

According to current roadmap, they will remain independent of core. This is partly because it allows for experimentation and competition and partly because different rollups may have unique features and tradeoffs. For example, one could imagine a privacy focused rollup or even a corporate rollup (maybe VISA could operate its own rollup) which might have additional requirements to participate. The tech is also very new at this stage, in particular with regards to zero knowledge rollups that operate on zkProofs. We don't really know what the limits of zk technology are, and it's best to allow for multiple competitors to experiment and try different approaches out.

The nice thing about rollups is that although they trade-off some centralization for scale, you can always escape hatch to layer 1 by posting a fraud proof of validity proof and your funds are secured by L1.

Eventually rollups will begin to decentralize themselves, as is the plan for some of the most promising rollups such as StarkNet and zkSync. Right now the sequencers and provers are operated by the founders of these organizations, but they will split these off into a federated network over the next year.

[everfree]

Those 3rd party L2 providers are inherent to Ethereum's scaling roadmap. No need to ossify them or integrate them tightly with the protocol layer, they can remain modular and in free market competition on the smart contract layer.