Hephaestus Model for Cross-Chain Transactions

This technical report presents Hephaestus, a model generator designed to enhance the security and performance of cross-chain transactions within blockchain ecosystems. The report outlines the increasing necessity for multi-chain applications and protocols, emphasizing their role in achieving scalability, privacy, and composability. It details the operational complexities associated with cross-chain applications and the prevalent security threats, particularly bridge attacks that have resulted in significant financial losses. The authors propose a framework that allows for the generation of cross-chain models from local transactions across different ledgers, facilitating the monitoring of cross-chain applications. This monitoring capability is crucial for identifying outliers and potential malicious activities, thereby providing a mechanism to mitigate bridge hacks. The report includes a detailed evaluation of the Hephaestus system, demonstrating its ability to process numerous cross-chain transactions efficiently while maintaining sublinear storage requirements. The findings underscore the importance of formalizing cross-chain logic to improve security and operational effectiveness.