论文标题
模拟拉格朗日编码计算
Analog Lagrange Coded Computing
论文作者
论文摘要
考虑了分布式计算方案,其中使用一组工人节点的计算能力在工人中分散的数据集上执行某些计算任务。由Yu等人提出的Lagrange编码计算(LCC)利用众所周知的Lagrange多项式在这种情况下以有效的并行方式对数据集进行多项式评估,同时在可能对工人勾结的情况下保留数据的隐私。该解决方案依靠将数据量化为有限的字段,因此,可以使用Shamir的秘密共享,作为其主要构件之一。但是,对于数据集的大小,这种解决方案无法正确扩展,这主要是由于计算溢出。为了解决这样的关键问题,我们提出了LCC向模拟域的新型扩展,称为模拟LCC(ALCC)。所提出的ALCC协议中的所有操作均在R/C的无限字段上完成,但对于实际实现,浮点数使用。我们将数据在ALCC中的隐私表征,而与区分安全性(DS)和相互信息安全性(MIS)指标的任何勾结工人的任何子集。同样,假设使用浮点数执行操作,则在实用环境中表征了结果的准确性。因此,观察到ALCC结果的准确性与其隐私水平的准确性之间的基本权衡,并对数字进行了评估。此外,我们实施了提出的方案,以在一批矩阵上执行矩阵矩阵乘法。可以观察到,与最新的LCC相比,ALCC是使用固定点号实现的最先进的LCC,假设这两个方案都使用相等数量的位来表示数据符号。
A distributed computing scenario is considered, where the computational power of a set of worker nodes is used to perform a certain computation task over a dataset that is dispersed among the workers. Lagrange coded computing (LCC), proposed by Yu et al., leverages the well-known Lagrange polynomial to perform polynomial evaluation of the dataset in such a scenario in an efficient parallel fashion while keeping the privacy of data amidst possible collusion of workers. This solution relies on quantizing the data into a finite field, so that Shamir's secret sharing, as one of its main building blocks, can be employed. Such a solution, however, is not properly scalable with the size of dataset, mainly due to computation overflows. To address such a critical issue, we propose a novel extension of LCC to the analog domain, referred to as analog LCC (ALCC). All the operations in the proposed ALCC protocol are done over the infinite fields of R/C but for practical implementations floating-point numbers are used. We characterize the privacy of data in ALCC, against any subset of colluding workers up to a certain size, in terms of the distinguishing security (DS) and the mutual information security (MIS) metrics. Also, the accuracy of outcome is characterized in a practical setting assuming operations are performed using floating-point numbers. Consequently, a fundamental trade-off between the accuracy of the outcome of ALCC and its privacy level is observed and is numerically evaluated. Moreover, we implement the proposed scheme to perform matrix-matrix multiplication over a batch of matrices. It is observed that ALCC is superior compared to the state-of-the-art LCC, implemented using fixed-point numbers, assuming both schemes use an equal number of bits to represent data symbols.