This rubric provides a comprehensive framework for assessing the effectiveness, fairness, and security of PBS strategies in Layer 2 blockchains. Each category and criterion can be tailored further to align with the specific goals and architecture of your Layer 2 protocol.
| Category | Criteria | Description | Scoring Guidelines |
|---|---|---|---|
| Sequencers | Centralized | Sequencers are centralized, leading to potential risks in terms of control and single points of failure. | Low score for centralization due to risks; high score for decentralization. |
| Sequencers | Shared | Sequencers are shared among multiple entities, providing a balance between centralization and decentralization. | Moderate score for shared sequencers, depending on the level of decentralization achieved. |
| Sequencers | Decentralized | Fully decentralized sequencers, minimizing risks associated with central control. | High score for fully decentralized sequencers, as it supports network security and resilience. |
| Proposers | Single | A single proposer is responsible for block proposals, which could centralize power. | Low score for single proposers due to centralization concerns. |
| Proposers | Round-Robin | Proposers are selected in a round-robin manner, distributing power more evenly among participants. | Moderate score for round-robin, as it helps distribute power but may still have limitations. |
| Proposers | Random Selection | Proposers are selected randomly, reducing predictability and centralization. | High score for random selection, as it reduces centralization and enhances fairness. |
| Proposers | Delegated | Proposers are delegated by token holders, introducing potential governance risks. | Score depends on how delegation is implemented and whether it avoids concentration of power. |
| Builders | Single | A single builder is responsible for constructing blocks, which may lead to centralization. | Low score for single builders due to centralization concerns. |
| Builders | Multiple | Multiple builders are involved in block construction, promoting competition and decentralization. | Higher score for multiple builders, as it promotes a healthy competitive environment. |
| Builders | Distributed Block Building | Block building is distributed among many entities, minimizing risks of centralization. | High score for distributed block building, as it supports decentralization and fairness. |
| Inclusion Lists | Static | Inclusion lists are static, which could limit flexibility in transaction selection. | Low score for static inclusion lists, unless they provide significant benefits for security or fairness. |
| Inclusion Lists | Dynamic | Inclusion lists are dynamic, allowing for more flexibility and adaptability in transaction selection. | High score for dynamic inclusion lists, as they enhance adaptability and efficiency. |
| Slashing Conditions | WIP | Evaluate the conditions under which proposers or builders may be penalized (slashed) to ensure alignment with network incentives. | Score depends on how slashing conditions align incentives and deter malicious behavior. |
| Proving | Proving Market | Proving is handled by a market-driven approach, potentially encouraging innovation but also introducing competition risks. | Score based on how the proving market affects decentralization and security. |
| Proving | Multi-Prover Setup | Multiple provers are involved, enhancing security but possibly at the cost of increased complexity and coordination. | Higher score for multi-prover setups that enhance security while maintaining efficiency. |
| Proving | TEEs (Trusted Execution Environments) | Provers use TEEs, which could offer strong security guarantees but might raise concerns about centralization or vendor control. | Score based on the trade-offs between security, centralization, and openness. |
| On-Chain vs. Off-Chain Solutions | On-Chain | The PBS implementation relies on on-chain mechanisms, which offer greater transparency and decentralization. | High score for on-chain solutions, as they enhance transparency, security, and decentralization. |
| On-Chain vs. Off-Chain Solutions | Off-Chain | The PBS implementation uses off-chain solutions, which might improve performance but introduce centralization risks. | Lower score for off-chain solutions, unless strong decentralization and security measures are in place. |
| Auctions | Block | Auctions are held for each block, allowing builders to bid for inclusion. | Score depends on transparency and fairness of the auction process. |
| Auctions | Timing Games | Auctions may involve timing games, potentially leading to inefficiencies. | Lower score if timing games introduce inefficiencies or unfair advantages. |
| Auctions | Bidding | WIP | |
| Auctions | Just-In-Time | WIP | |
| Auctions | Ahead-Of-Time | Execution Tickets (Execution Auctions) |
This work is made possible by a grant from the PBS Foundation and support from Blockdaemon.
This rubric aims to help Layer 2 developers and the broader blockchain community enhance fairness, efficiency, and decentralization in PBS approaches, particularly in relation to equitable MEV distribution.
You can use this rubric as a reference to evaluate the PBS strategies within your Layer 2 protocol. It helps identify strengths and areas for improvement to ensure a balanced approach to decentralization and efficiency.
We welcome contributions to improve this rubric. Please feel free to submit your suggestions via a pull request or open an issue to discuss improvements.
This project is licensed under the MIT License - see the LICENSE file for details.