The features, hardware, and architectures of data center networks: A survey

• We give a survey on the features and hardware of Data Center Networks.
• We thoroughly analyze the topology designs and architectures of DCNs.
• We provide both qualitative and quantitative analyses on the features of DCNs.

The rapid development of cloud computing in recent years has deeply affected our lifestyles. As core infrastructures of cloud computing, data centers have gained widespread attention from both the academia and industry. In a data center, the data center network (DCN) that plays a key role in computing and communication has attracted extensive interest from researchers. In this survey, we discuss the features, hardware, and architectures of DCN’s, including their logical topological connections and physical component categorizations. We first give an overview of production data centers. Next, we introduce the hardware of DCN’s, including switches, servers, storage devices, racks, and cables used in industries, which are highly essential for designing DCN architectures. And then we thoroughly analyze the topology designs and architectures of DCN’s from various aspects, such as connection types, wiring layouts, interconnection facilities, and network characteristics based on the latest literature. Finally, the facility settings and maintenance issues for data centers that are important in the performance and the efficiency of DCN’s are also briefly discussed. Specifically and importantly, we provide both qualitative and quantitative analyses on the features of DCN’s, including performance comparisons among typical topology designs, connectivity discussion on average degree, bandwidth calculation, and diameter estimation, as well as the capacity enhancement of DCN’s with wireless antennae and optical devices. The discussion of our survey can be referred as an overview of the ongoing research in the related area. We also present new observations and research trends for DCN’s.