CAREER: Secure Multi-Party Protocols

职业建议书获奖摘要在这个项目中，我们为各种多方协议任务设计了高效的安全算法。协议必须是可证明安全的，基于公认的密码学假设，它们需要满足这些协议的实际应用所要求的要求，并且它们需要足够的效率才能在实践中使用。设计这类议定书的挑战是在不作出妨碍在实践中采用这些议定书的假设的情况下实现效率。例如，依赖于公钥基础设施的协议不能承担普遍信任的权威机构，如果协议参与者持有来自多个来源的证书，则它们应该保持高效。此外，为了真正有用，多方协议必须在现实的通信条件下保持有效，例如，如果参与节点没有同步的时钟，或者任何两个协议参与者之间的通信机制可能被破坏。开发满足这些效率目标和操作要求的高效安全多方协议依赖于构建具有新的安全属性的公钥原语，并找到新的方法来解决与多方协议相关的基本问题，例如公平性、信任假设施加的限制和协议组合下的安全性。该项目还可以对各种计算机系统产生直接影响，提高它们的可靠性、安全性、和隐私属性。我们的协议的潜在应用的例子是提供容错安全服务，以及在自组织和移动网络中启用组范围的安全机制。

Award Abstract for CAREER proposal 0747541In this project we design efficient secure algorithms for various multi-party protocol tasks. The protocols must be provably secure based on well-understood cryptographic assumptions, they need to satisfy requirements imposed by the real-world applications of these protocols, and they need to be efficient enough to be usable in practice.Among the protocol tasks we address are private authentication schemes, aggregate signature schemes, dynamic group key agreement schemes, and proactive cryptosystems. The challenge in designing such protocols is to achieve efficiency without making assumptions that would impede the adoption of these protocols in practice. For example, protocols that rely on a public key infrastructure cannot assume universally trusted authorities, and they should remain efficient if protocol participants hold certificates from multiple sources. Moreover, to be truly useful a multi-party protocol must remain efficient in realistic communication conditions, e.g. if the participating nodes do not have synchronized clocks, or if the communication mechanism between any two protocol participants can be disrupted.Development of efficient secure multi-party protocols which meet these efficiency goals and operational requirements relies on construction of public key primitives with novel security properties, and on finding new approaches to fundamental questions related to multi-party protocols, e.g. fairness, limitations imposed by trust assumptions, and security under protocol composition.This project can also have an immediate impact on a variety of computer systems, improving their reliability, security, and privacy properties. Examples of prospective applications of our protocols are provision of fault-tolerant security services, and enabling of group-wide security mechanisms in ad-hoc and mobile networks.