Collaborative Research: SaTC: CORE: Medium: A Networking Perspective of Blockchain Security: Modeling, Analysis, and Defense

区块链已经成为一种“安全设计”技术，它可以在一组相互不信任的节点之间提供安全性，而不依赖于可信的中央权威。区块链的基本安全性基于分布式共识，它假设只要整个网络的计算（或投票）能力的某个阈值（大于一半）是诚实的，系统就是安全的。然而，在现实中，有许多因素可以有效地改变这个阈值，从而显著降低区块链安全性。该项目旨在通过开发新的理论和系统来解决区块链技术中的这些基本安全挑战，以获得更深入的理解并指导新的防御解决方案的开发。项目团队将调查大型矿池中的集群电力、异构网络连接和恶意点对点网络链路操纵如何影响区块链的基本安全性。外部数据馈送是区块链技术更广泛应用面临的另一个基本安全挑战。因此，该项目的另一个目标是解决数据真实性挑战，其中外部拜占庭源可能向区块链应用程序提供错误输入。该项目的研究活动主要集中在三个方面。首先，该团队将通过对共识协议、网络连通性和系统中其他因素的建模和分析来检查区块链的基本安全属性，目标是提供关于区块链运行的公平性、活动性和安全性的可量化见解。其次，将调查可信计算的使用，以启用远程可证明的策略驱动的软件定义网络，以防御和减轻对b区块链的基于路由的攻击。第三，该团队将设计一种新颖的可信数据馈送机制，利用分散的真相发现和链下高效协议来解决区块链应用程序长期存在的数据真实性挑战。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Blockchain has emerged as a "secure by design" technology that can provide security among a group of mutually distrustful nodes without relying on a trusted central authority. The fundamental security of the blockchain is based on distributed consensus, which assumes the system is secure as long as a certain threshold amount (greater than half) of the whole network's computing (or voting) power is honest. However, in reality, many factors can effectively change this threshold, significantly impairing blockchain security. This project aims to address these fundamental security challenges in blockchain technology by developing new theories and systems to gain a deeper understanding and guide the development of new defense solutions. The project team will investigate how clustered power in large mining pools, heterogeneous network connectivity, and malicious peer-to-peer network link manipulation can impact fundamental blockchain security. The external data feed is another fundamental security challenge towards the broader application of blockchain technology. Therefore, another goal of the project is to address the data truthfulness challenge, where external Byzantine sources may supply false inputs to the blockchain applications. The research activities of this project focus on three main thrusts. First, the team will examine the fundamental security properties of blockchain through the lens of modeling and analysis of consensus protocols, network connectivity, and other factors in the system, with the goal of providing quantifiable insights on fairness, liveness, and safety of blockchain operation. Second, the will investigate the use of trusted computing to enable remotely attestable policy-driven software-defined networks for defense and mitigation of routing-based attacks on blockchain. Third, the team will design a novel trustworthy data feed mechanism that leverages decentralized truth discovery and off-chain efficient agreement to address the long-standing data truthfulness challenge for blockchain applications.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.