In distributed storage systems, cooperative regenerating codes tradeoff storage for repair bandwidth in the case of multiple node failures. In rack-aware distributed storage systems, there is no cost associated with transferring symbols within a rack. Hence, the repair bandwidth will only take into account cross-rack transfer. Rack-aware regenerating codes for the case of single node failures have been studied and their repair bandwidth tradeoff characterized. In this paper, we consider the framework of rack-aware cooperative regenerating codes for the case of multiple node failures where the node failures are uniformly distributed among a certain number of racks. We characterize the storage repair-bandwidth tradeoff as well as derive the minimum storage and minimum repair bandwidth points of the tradeoff. We also provide constructions of minimum bandwidth rack-aware cooperative regenerating codes for all parameters.

中文翻译：

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机架感知的协作再生代码

在分布式存储系统中，在多个节点发生故障的情况下，协作再生代码会权衡存储以修复带宽。在可识别机架的分布式存储系统中，与在机架内传输符号无关的成本。因此，维修带宽将仅考虑跨机架传输。已经研究了针对单节点故障的机架感知再生代码，并描述了其修复带宽的权衡特性。在本文中，我们考虑了在多个节点故障情况下机架感知的协作再生代码框架，在这种情况下，节点故障均匀分布在一定数量的机架中。我们表征了存储修复带宽权衡，并得出了最小存储和最小修复带宽点的权衡。