"Sovereign" Rollup L1s vs "Settled" L2s
Last updated
Last updated
ABC Stack is the framework for building sovereign rollups on Celestia that achieves gigagas-level throughput.
ABC embraces true modularity by cleanly separating core blockchain functions and removing unnecessary coupling between components.
L2 rollups are defined by their relationship with a settlement layer (typically Ethereum). They require an enshrined bridge - a mandatory smart contract bridge to the settlement layer that's built directly into the rollup's protocol. State commitments and proofs get posted to the settlement layer, which creates a dependency where the rollup relies on this layer for validation and security guarantees. Additionally, because these rollups must coordinate protocol changes with the settlement layer, they cannot evolve independently or implement changes that might conflict with the base layer's rules or capabilities.
This architecture creates several limitations. The enshrined bridge introduces significant computational overhead. For optimistic rollups, the 7-day fraud proof challenge period has led many users to rely on third-party liquidity providers to bridge assets more quickly. Additionally, the requirement to maintain synchronization with the settlement layer adds substantial complexity to the rollup client, which must constantly monitor for reorgs and manage state transitions between chains.
Rollup L1s are both modular and sovereign; they define themselves by their independence.
Unlike L2s that rely on an enshrined smart contract on another blockchain, Rollup L1s maintain sovereignty through self-defined state validation, where the correct chain state is determined by the rollup's own network of nodes.
This independence extends to settlement as well - Rollup L1s have no mandatory bridging to another chain, allowing them to operate without any bridge at all if desired. When bridges are needed, they benefit from modular bridging, with the freedom to choose any bridging solution that best serves their specific needs.
Perhaps most importantly, Rollup L1s maintain protocol sovereignty, which allows them to evolve through independent governance and social consensus just like traditional L1s, giving communities the power to determine their own upgrade paths and future direction without requiring permission from an underlying settlement layer.
In terms of verification, L2s requires running both the rollup node and the settlement node to determine settlement finality. In contrast, for Rollup L1s, the rollup node itself serves as the settlement node, and only needs to be run in conjunction with a DA node (e.g., a Celestia light node).
Regarding finality, L2 Rollups have a dependency on two separate layers, requiring both the settlement layer and the data availability layer to finalize before transactions can be considered complete. This dual dependency can introduce delays and complications. Rollup L1s, however, only require the data availability layer to finalize, which creates a more direct path to transaction finality.
For asset issuance, L2 Rollups were originally designed with the assumption that assets would primarily originate on the settlement layer and then move to the L2 for operations. This design creates a dependency on the settlement layer for asset origination. Rollup L1s break free from this constraint, offering the ability to natively issue assets without any inbuilt reference to another chain, providing greater autonomy for applications and ecosystems.
Perhaps the most significant difference lies in bridging capabilities. L2 Rollups must always maintain their enshrined bridge to the settlement layer, even if it's rarely or never used. By contrast, Rollup L1s provide maximum flexibility – they can operate with no bridges at all (for self-contained ecosystems), or they can implement any bridging solution that best meets their specific requirements. This modular approach to bridging allows Rollup L1s to optimize for their particular use cases without forcing unnecessary components into their architecture.
Rollup L1s represent the next evolution of rollups based on our observations of how developers and users actually interact with blockchain systems. While rollups were initially designed with the assumption that maximum security required anchoring all state transitions to Ethereum and that users would first mint tokens on Ethereum and bridge to L2, experience has shown that this design does not align with an increasing number of blockchain use cases.
Celestia is the first modular consensus and data availability network. It provides the foundation that powers sovereign rollups by deeply focusing on two of the core blockchain functions:
Consensus: Providing secure transaction ordering through proof-of-stake
Data Availability: Ensuring data is published and available through data availability sampling (DAS)
By specializing in these functions, Celestia can maintain security while scaling to handle massive amounts of data, which is why Celestia’s modular network serves as an ideal base for ABC Stack’s high-throughput execution layers to build on top.
