Wireless Data Center Networks: Advances, Challenges, and Opportunities

TL;DR

This paper reviews recent advances, challenges, and future opportunities in wireless data center networks, highlighting their potential to improve flexibility, bandwidth utilization, fault-tolerance, and energy efficiency over traditional wired solutions.

Contribution

It provides a comprehensive comparison of wireless communication technologies and discusses key design challenges and research opportunities in the development of wireless data center networks.

Findings

Wireless WDCNs can enhance bandwidth efficiency and fault-tolerance.

Wireless links reduce cabling costs and improve energy efficiency.

The paper identifies open research challenges and future directions in WDCNs.

Abstract

Data center networks (DCNs) are essential infrastructures to embrace the era of highly diversified massive amount of data generated by emerging technological applications. In order to store and process such a data deluge, today's DCNs have to deploy enormous length of wires to interconnect a plethora of servers and switches. Unfortunately, wired DCNs with uniform and inflexible link capacities expose several drawbacks such as high cabling cost and complexity, low space utilization, and lack of bandwidth efficiency. Wireless DCNs (WDCNs) have emerged as a promising solution to reduce the time, effort, and cost spent on deploying and maintaining the wires. Thanks to its reconfigurability and flexibility, WDCNs can deliver higher throughputs by efficiently utilizing the bandwidth and mitigate the chronic DCN problems of oversubscription and hotspots. Moreover, wireless links enhance the fault-tolerance and energy efficiency by eliminating the need for error-prone power-hungry switches. Accordingly, this paper first compares virtues and drawbacks of millimeter wave (mmWave), terahertz (THz), and optical wireless communications as potential candidates. Thereafter, an in-depth discussion on advances and challenges in WDCNs is provided including physical and virtual topology design, quality of service (QoS) provisioning, flow classification, data grooming, and load balancing. Finally, exciting research opportunities are presented to promote the prospects of WDCNs.