Layer-2 Scaling
Research Papers
Academic and industry research
Sprites and State Channels: Payment Networks that Go Faster than Lightning
Andrew Miller, Iddo Bentov, Ranjit Kumaresan, Patrick McCorry
This paper presents 'Sprites,' an innovative protocol designed to improve payment channel networks by enabling rapid, multi-hop payments with strong safety guarantees. The authors identify challenges in existing lightning-style networks, such as the need for long-term lockups of capital and complex transaction handling. Sprites introduces the use of virtual channels and a novel time-based locking mechanism that allows for atomic multi-hop payments without requiring all intermediate nodes to be online simultaneously for the duration of the payment process. By reducing the reliance on specific timing and synchronization constraints found in earlier state channel designs, the protocol achieves greater efficiency and usability. The research provides critical insights into the optimization of off-chain payment structures, addressing fundamental limitations in pathfinding, settlement speed, and overall network capital efficiency within decentralized finance.
Fuel: The first optimistic rollup on Ethereum
John Adler
This whitepaper introduces Fuel, an early implementation of the optimistic rollup paradigm for Ethereum. The core methodology involves moving execution off-chain while anchoring transaction data on the Ethereum mainnet, relying on fraud proofs to ensure the correctness of state transitions. Fuel focuses specifically on high-throughput execution by utilizing a unique script-based model that avoids the limitations of account-based models under heavy load. The paper explains the design of the rollup, the process of submitting batch data to the L1, and the security model underlying the fraud-proof system. As one of the foundational papers on optimistic rollups, Fuel contributed to the shift in Ethereum's scaling strategy from pure sidechains toward rollups, which leverage the security of the underlying base layer, setting a precedent for modular blockchain architectures.
Cairo – a Turing-complete language for efficient scaling of blockchains
Lior Goldberg, Shahar Papini, Michael Riabzev
This paper introduces Cairo, a specialized programming language designed for writing provable programs that can be executed on a STARK-based verifiable computation system. Cairo enables developers to create complex, Turing-complete logic that is then converted into a proof by a prover and verified by a verifier. This is a foundational step for ZK-Rollups, as it allows for the off-chain execution of smart contracts with on-chain verification, significantly reducing computational overhead. The paper details the Cairo CPU architecture, the instruction set, and the methodology for proving non-deterministic computational tasks. Its contribution is pivotal for the Web3 ecosystem, as it provides a practical pathway toward scaling Ethereum through computational integrity proofs rather than merely relying on data availability, facilitating highly complex, scalable decentralized applications.