Wireless Communication in Data Centers: A Survey

Abstract

Abstract-Data centers (DCs) is becoming increasingly an integral part of the computing infrastructures of most enterprises. Therefore, the concept of DC networks (DCNs) is receiving an increased attention in the network research community. Most DCNs deployed today can be classified as wired DCNs as copper and optical fiber cables are used for intra-and inter-rack connections in the network. Despite recent advances, wired DCNs face two inevitable problems; cabling complexity and hotspots.To address these problems, recent research works suggest the incorporation of wireless communication technology into DCNs. Wireless links can be used to either augment conventional wired DCNs, or to realize a pure wireless DCN. As the design spectrum of DCs broadens, so does the need for a clear classification to differentiate various design options. In this paper, we analyze the free space optical (FSO) communication and the 60 GHz radio frequency (RF), the two key candidate technologies for implementing wireless links in DCNs. We present a generic classification scheme that can be used to classify current and future DCNs based on the communication technology used in the network. The proposed classification is then used to review and summarize major research in this area. We also discuss open questions and future research directions in the area of wireless DCs.Index Terms-Wireless data centers, 60 GHz, free space optical (FSO), optical wireless communication (OWC), data centers, data center network.

Beyond 5G - wireless data center connectivity

“…The THz region here is a key field of development, combining many of the properties of radio communications with the possibility to employ techniques for controlling and directing the signal in free space more commonly found in optics, such as collimators, lenses and mirrors. 13 Beyond the THz range, at much higher frequencies, optical wireless communications, where optical signal are transmitted through open space with collimated beams, rather than guided via optical fiber, can offer significant capacities and has been suggested as an alternative for data center networking. 13,24 While the typical telecommunications and fiber optics wavelengths -at 850 nm, 1310 nm and 1550 nm -are obvious candidate for such free space optics (fso) implementations, the available spectrum is much larger and extends across the entire infrared region and beyond to visible light.…”

“…Wireless data center networking has been introduced to improve data center connectivity and circumvent current bottlenecks or even to enable fully wireless data centers. [10][11][12][13][14][15] Innovative wireless terminals, air interfaces, and network transmission technologies are accelerating the evolution not only of devices, but also of architectures. Mobile data-centers can replace hundreds of meters of cable withmillimeter wave (mm-wave) wireless connections along with servers addressing both intra-and inter-rack connections.…”

Optical wireless communications for airport surface operations: Opportunities and challenges

“…OWC combines the flexibility of wireless communication and the high speed and bandwidth of optical communication. As its enabling technologies rapidly advance, OWC is finding its place in many indoor, outdoor, space and underwater applications, such as indoor local area networks and data centers [4][5], mobile networks backhaul [6], space communication [7], and underwater sensing [8].…”

Layout-Independent Wireless Facility Constructing and Scheduling for Data Center Networks

“…Whenever there are available wireless links and there are isolated racks, Algorithm 1 chooses a wireless link from the link set in steps (7)- (16). Note that in order to ensure the connectivity of the WFN, we may need to adjust some radios' positions or install new reflectors to increase the number of feasible wireless links in steps (20) and (21).…”

“…Input: Topology graph G(V, E), , , route length limit Output: a set of routes for ( , ) (1) Tabu list T = 0, Route set S = 0, Node set N = { }; (2) for each node in set N do (3) if the length of the path from to is larger than then (4) Break; (5) end (6) for each neighbor a of node do (7) if a is equal to then (8) Add the path from to in the tree to S; (9) Add the nodes in the path to T except ; (10) else (11) if a is already included in T then (12) Cut and the subtree rooted at from the tree; (13) end (14) end (15) Add to N if ∉ N; (16) end (17) Remove from N; (18) end (19) Return S Algorithm 2: Route calculation.…”