论文标题
安全的分布式算法没有硬度假设
Secured Distributed Algorithms Without Hardness Assumptions
论文作者
论文摘要
我们在分布式消息模型中研究算法,该算法为输入图$ g $而产生安全输出。具体来说,每个顶点都在输出中计算其部分,整个输出都是正确的,但是每个顶点无法以一定的概率发现其他顶点的输出。这是由当今嵌入在各种设备中的高性能处理器的动机。在这种情况下,它不再是有道理的,在许多情况下,将整个处理任务留给一台计算机甚至一组中央计算机是不可行的。由于分布式算法领域的广泛研究产生了许多经典问题的有效分散算法,因此对分布式算法安全性的讨论被忽略了。然而,在安全多方计算问题(MPC或SMC)的研究领域中设计了许多方案和算法。但是,这些协议的概念和术语与经典分布式算法完全不同。结果,这些协议的重点是为每个函数$ f $工作,以增加复杂性或需要几个计算假设的必要性。在这项工作中,我们提出了一种新颖的方法,该方法并没有将现有算法变成安全的算法,而是识别并开发了固有安全的算法(这意味着它们不需要任何进一步的结构)。这种方法为各种地方问题提供了有效的安全算法,例如着色,网络分解,森林分解以及各种其他标签问题。值得注意的是,我们的方法不需要任何硬度假设,而只需要每个顶点中的私人随机性发生器。这与基于公开加密方案的以前已知技术相反。
We study algorithms in the distributed message-passing model that produce secured output, for an input graph $G$. Specifically, each vertex computes its part in the output, the entire output is correct, but each vertex cannot discover the output of other vertices, with a certain probability. This is motivated by high-performance processors that are embedded nowadays in a large variety of devices. In such situations, it no longer makes sense, and in many cases it is not feasible, to leave the whole processing task to a single computer or even a group of central computers. As the extensive research in the distributed algorithms field yielded efficient decentralized algorithms for many classic problems, the discussion about the security of distributed algorithms was somewhat neglected. Nevertheless, many protocols and algorithms were devised in the research area of secure multi-party computation problem (MPC or SMC). However, the notions and terminology of these protocols are quite different than in classic distributed algorithms. As a consequence, the focus in those protocols was to work for every function $f$ at the expense of increasing the round complexity, or the necessity of several computational assumptions. In this work, we present a novel approach, which rather than turning existing algorithms into secure ones, identifies and develops those algorithms that are inherently secure (which means they do not require any further constructions). This approach yields efficient secure algorithms for various locality problems, such as coloring, network decomposition, forest decomposition, and a variety of additional labeling problems. Remarkably, our approach does not require any hardness assumption, but only a private randomness generator in each vertex. This is in contrast to previously known techniques in this setting that are based on public-key encryption schemes.