With the continuously growing popularity of cloud services, the traffic volume inside the data centers is dramatically increasing. As a result, a scalable and efficient infrastructure for data center networks (DCNs) is required. The current optical DCNs using either individual fibers or fiber ribbons are costly, bulky, hard to manage, and not scalable. Spatial division multiplexing (SDM) based on multicore or multimode (few-mode) fibers is recognized as a promising technology to increase the spatial efficiency for optical DCNs, which opens a new way towards high capacity and scalability. This tutorial provides an overview of the components, transmission options, and interconnect architectures for SDM-based DCNs, as well as potential technical challenges and future directions. It also covers the co-existence of SDM and other multiplexing techniques, such as wavelength-division multiplexing and flexible spectrum multiplexing, in optical DCNs.

中文翻译：

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光数据中心网络的使能技术：空分复用

随着云服务的不断普及，数据中心内部的流量急剧增加。因此，需要用于数据中心网络 (DCN) 的可扩展且高效的基础设施。当前使用单根光纤或光纤带的光学 DCN 成本高、体积大、难以管理且不可扩展。基于多芯或多模（少模）光纤的空分复用 (SDM) 被认为是一种提高光 DCN 空间效率的有前途的技术，为实现高容量和可扩展性开辟了一条新途径。本教程概述了基于 SDM 的 DCN 的组件、传输选项和互连架构，以及潜在的技术挑战和未来方向。它还涵盖了 SDM 和其他复用技术的共存，