Hephaestus: Modelling, Analysis, and Performance Evaluation of Cross-Chain Transactions

Abstract

<p>Ecosystems of multiple blockchains are now a reality. Multi-chain applications and protocols are perceived as necessary to enable scalability, privacy, and composability. Despite being a promising emerging research area, we recently have witnessed many attacks that have caused billions of dollars in losses. Attacks against bridges that connect chains are at the top of such attacks in terms of monetary cost, and no apparent solution seems to emerge from the ongoing chaos. </p> <p>In this paper, we present our contribution to minimizing bridge attacks. In particular, we explore the concepts of <em>cross-chain transaction, cross-chain logic, </em>and the<em> cross-chain state</em> as the enablers of the cross-chain model. We propose <strong>Hephaestus</strong>, the first cross-chain model generator that captures the operational complexity of cross-chain applications. <strong>Hephaestus</strong> can generate cross-chain models from local transactions on different ledgers realizing arbitrary use cases and allowing operators to monitor their cross-chain applications. Monitoring helps identify outliers and malicious behavior, which can help programmatically to stop bridge hacks and other attacks. We conduct a detailed evaluation of our system, where we implement a cross-chain bridge use case. Our experimental results show that <strong>Hephaestus </strong>can process 600 cross-chain transactions in less than 5.5 seconds in an environment with two blockchains and requires sublinear storage.</p>

Can We Share the Same Perspective? Blockchain Interoperability with Views

“…In this section, we discuss BUNGEE. The proliferation of blockchain interoperability solutions is increasing interest in exploring cross-chain logic and the need to model and analyze it [8]. Our proposal constitutes the foundation to make sense of that diversity by allowing to systematically create and integrate views from different blockchains.…”

“…The first use case is cross-chain state creation, management, and visualization. Although some preparatory work has been done [37,8], it is difficult to visualize and reason about private data partitions (different views), not only in the cross-chain setting but also in a single blockchain setting. Blockchain platforms could leverage views to improve view analysis for auditors, cybersecurity experts, and developers.…”

“…In this context, building and analyzing views is important to accurately understand each stakeholder's view of each DLT as a tool for interoperability, but also for business intelligence (e.g., for better understanding a protocol) or auditing (e.g., monitoring a protocol) [8]. Views directly support blockchain interoperability since it is easier to share the perspectives of all participants across heterogeneous DLTs [6,9], allowing a better representation of the business ecosystem.…”

SoK: Security and Privacy of Blockchain Interoperability [Extended Version]

“…As a common vulnerability, forks can be created in these protocols, as more valid blocks are mined in parallel suffixing a determined block in the chain. If these block headers are relayed to the target chain before being considered final, actions based on them should not be successful in guaranteeing the absence of safety violations -e.g., double spending or other violations of cross-chain logic [32]. This main chain identification increases the complexity of the bridge contract in the destination chain.…”

CBDC bridging between Hyperledger Fabric and permissioned EVM-based blockchains

“…Even in the permissionless blockchain world, cross-chain interoperability is still an emerging area (see, e.g., the survey [13]). There are still significant gaps in the necessary and proper formal treatment of approaches, including the characterization of interoperability behavior and thus allowing for monitoring and proactive security ( [10] is an important step forward) and an overall lack of standards.…”