No-exchange data center internal network architecture based on free space optical communication

Abstract

The invention discloses a non-exchange data center internal network architecture based on free space optical communication, and belongs to the technical field of optical communication and data center networks. According to the framework, a server with a tunable light emitter, a light distribution beam combiner and the like are arranged in a cabinet, and non-line-of-sight communication is realized through a spatial light element; all-optical routing is completed through wavelength, spatial mode and time slot joint multiplexing, and a traditional electric / optical switch is not needed. The optical path routing in the architecture adopts passive devices, optical fiber wiring is avoided, online expansion of a cabinet and a server is supported, deployment and energy consumption cost is remarkably reduced, high-bandwidth, low-delay and low-power-consumption green data center communication is achieved, and the system can be widely applied to scenes such as cloud computing and big data.

Description

TECHNICAL FIELD

[0001] The application relates to a data center internal network architecture based on free space optical communication and belongs to the technical fields of optical communication, data center network and wireless optical communication. BACKGROUND

[0002] As the core infrastructure supporting cloud computing, big data, Internet of Things and other modern information services, data centers bear the key task of high-speed data exchange between servers and cabinets. With the explosive growth of data traffic, traditional data center networks based on wired connections such as optical fibers and copper cables face severe challenges in terms of deployment cost, space utilization, energy consumption control and topology reconstruction. Especially under the background of the "double carbon" strategy, building a green, low-carbon and efficient data center has become an urgent demand for industry development.

[0003] Currently, data center internal communication mainly relies on electrical switching and optical switching technologies and is interconnected through a large number of optical fiber links. Although optical switching has advantages in terms of bandwidth and delay, it still requires intensive wiring, resulting in system complexity, limited scalability, maintenance difficulties and linear energy consumption growth with server size. In addition, the large number of switching devices not only increases the power consumption burden but also increases the management complexity. Optical switching itself also faces key technical bottlenecks such as nanosecond-level switching control, optical cache missing and clock synchronization overhead, which restrict its widespread application in large-scale dynamic networks.

[0004] Free space optical communication (FSO) as a wireless optical transmission technology without physical media has advantages such as high bandwidth, low delay, wiring-free, easy reconfiguration, etc. In recent years, it has been gradually introduced into the data center internal communication scenario. Existing research attempts to use ceiling mirrors, movable mirrors, spatial light modulators (SLM) and other devices to realize cabinet-to-cabinet or cabinet-to-cabinet communication, and has preliminarily verified the feasibility of FSO in short-distance high-speed communication. However, the existing schemes have problems such as high alignment accuracy requirement, poor system stability, lack of complete network architecture support, etc., and have not yet formed a complete solution that is scalable, low-power and exchange-free.

[0005] Therefore, there is an urgent need for a new data center internal network architecture based on FSO technology to break through the limitations of traditional wired interconnection and centralized switching, enabling high-bandwidth, low-latency, low-power and easy-to-reconfigure data center communication without the need for switches and fiber wiring, and providing a practical technical path for building the next generation of green, intelligent and scalable data centers. SUMMARY

[0006] To address the challenges of complex fiber optic cabling, high power consumption of switching equipment, and difficulties in topology reconfiguration within existing data center networks, this invention proposes a switchless data center network architecture based on free-space optical communication. By employing Mode Division Multiplexing (MDM) and Wavelength Division Multiplexing (WDM) technologies, low-latency, low-power data exchange between servers within a rack and servers across racks is achieved without using traditional electrical / optical switches.

[0007] The technical solution of the present invention: A data center internal network architecture based on free-space optical communication, the architecture comprising: The cabinet includes servers with tunable optical transmitters, beam combiners, mode demultiplexers, mirrors, arrayed waveguide gratings (AWG), cabinet / optical controllers, and top mirrors.

[0008] This data center network architecture uses different wavelengths to control optical signals to different servers within a rack, and different modes to control the optical signals to different racks. The mode determines the destination rack, and the mode allocation strategy uses a cyclic matrix method, statically assigning an orthogonal spatial mode to each source-destination rack pair. The wavelength determines the destination server; each server can generate optical signals of all wavelengths and all modes, but each server can only receive optical signals of one wavelength. Within each rack, the wavelength allocation strategy for all servers within a cycle uses a cyclic matrix method, ensuring that different servers generate different wavelengths within a time slot, thus preventing interference. Furthermore, each server can traverse all wavelengths within a cycle, enabling communication with any other server within the data center. A server can determine the origin of a signal from a specific rack and server based on the received signal's time slot, wavelength, and mode.

[0009] Each rack houses several servers that generate and receive optical signals. Each server contains a tunable optical transmitter that modulates data signals to a specific wavelength and spatial mode, supporting mode-division multiplexing (MDF) and wavelength-division multiplexing (WDM). Each rack's transmitting end is equipped with a beam combiner and a mode demultiplexer. The beam combiner combines optical signals from various servers within the rack into a single beam, while the mode demultiplexer separates the received beams according to different modes and directs them to the target rack. Non-line-of-sight (NLOS) free-space optical communication is achieved between racks via ceiling reflectors. Fixed spatial optical elements such as reflectors, lenses, and collimators are used to set the beam propagation path, enabling cross-rack data transmission. Each rack's receiving end is equipped with an AWG and a mode demultiplexer. The AWG directs the optical signal to the target server according to the wavelength, while the mode demultiplexer identifies optical data packets from different sources and recovers their original data. The network system employs a three-dimensional joint multiplexing mechanism of wavelength, spatial mode, and time slot, achieving all-optical routing and dynamic reconfiguration without relying on traditional optical / electrical switches.

[0010] The beneficial effects of this invention are as follows: 1. Routing is achieved through wavelength and mode joint multiplexing, eliminating the need for traditional electrical / optical switches. Furthermore, most components are passive (such as AWGs, mode multiplexers / demultiplexers, beam combiners, and mirrors), significantly reducing the overall energy consumption of the data center.

[0011] 2. It adopts free-space optical communication, eliminating the need for fiber optic cabling and reducing deployment and maintenance costs.

[0012] 3. Supports flexible expansion of the number of server racks and servers, with high scalability. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0014] Figure 1 This is a schematic diagram of the overall structure of the internal network of the data center according to an embodiment of the present invention. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention.

[0016] Example 1 This invention provides an internal network architecture for a data center based on free-space optical communication, as shown in the embodiments below. Figure 1 As shown. The internal network architecture of the data center consists of a cabinet (1), a server (2), a beam combiner (3), a mode demultiplexer (4), a mirror (5), an AWG (6), a cabinet / optical controller (7), and a top mirror (8).

[0017] Servers (21, 22, 23, 24) within rack (11) generate optical signals of arbitrary modes and different wavelengths within the same time slot and send them to beam combiner (3). Beam combiner (3) combines the optical signals sent by servers (21, 22, 23, 24) and sends them to mode demultiplexer (41). Mode demultiplexer (41) determines whether the signal is internal rack communication or cross-rack communication based on the mode of the optical signal and sends the signal to the corresponding output port. If it is internal rack communication, the mode demultiplexer (41) sends the signal to the corresponding internal rack communication output port. The signal output from the output port is reflected by the reflector (51) and sent to the input port of the AWG (61) in the internal rack communication demodulation area. The AWG (61) sends the signal to the corresponding server according to the wavelength of the signal. If it is cross-rack communication, the mode demultiplexer (41) sends the signal to the corresponding cross-rack communication output port. The signal output from the output port is reflected by the reflector (52) and sent to the rack / optical controller (7) above the rack. The rack / optical controller sends the signal to the set path, passes through the top reflector (8), and sends the signal to the cross-rack communication demodulation area of ​​the corresponding rack. The cross-rack communication demodulation area first sends the signal to the corresponding server through the AWG (62), and then through the mode demultiplexer (42, 43, 44, 45) to the input port of the server in different modes, so as to realize communication between cross-rack servers.

Claims

1. A free-space optical communication based exchangeless data center intra-network architecture, characterized in that, The cabinet (1) is internally provided with a plurality of servers (2), each server (2) is provided with a tunable optical transmitter for modulating data signals to a specific wavelength and spatial mode and supporting mode division multiplexing and wavelength division multiplexing; a beam combiner (3) is arranged in the emission area of the cabinet (1) and is used for combining the optical signals emitted by each server (2) in the cabinet into one optical beam; a mode demultiplexer (4) is used for separating the received optical beam into an intra-cabinet communication optical beam or a cross-cabinet communication optical beam according to the spatial mode; a mirror (5) is used for reflecting the intra-cabinet communication optical beam to an arrayed waveguide grating (6) in the cabinet, or reflecting the cross-cabinet communication optical beam to a cabinet / optical controller (7); the arrayed waveguide grating (6) is arranged at the receiving end of the cabinet (1) and is used for guiding the intra-cabinet communication optical beam to a target server (2) according to the wavelength; the cabinet / optical controller (7) is used for guiding the cross-cabinet communication optical beam to a top mirror (8); the top mirror (8) is used for reflecting the cross-cabinet communication optical beam to the arrayed waveguide grating (6) and the mode demultiplexer (4) of a target cabinet, so as to realize non-line-of-sight free space optical communication; the network architecture realizes three-dimensional joint multiplexing of wavelength, spatial mode and time slot, and completes all-optical routing without setting a traditional electrical / optical switch.

2. The network architecture of claim 1, wherein, The positions and functions of the mode multiplexer (4) and the arrayed waveguide grating (6) can be interchanged, that is, the arrayed waveguide grating (6) is used for separating the received optical beam into an intra-cabinet communication optical beam or a cross-cabinet communication optical beam according to the wavelength; and the mode multiplexer (4) is used for guiding the communication optical beam to a target server (2) according to the spatial mode.

3. The network architecture of claim 1, wherein, The tunable optical transmitter generates optical signals of different wavelengths and different spatial modes.

4. The network architecture of claim 1, wherein, The mode demultiplexer (4) adopts a cyclic matrix allocation strategy, so that any spatial mode emitted by any cabinet is only directed to a unique target cabinet.

5. The network architecture of claim 1, wherein, The wavelength allocation strategy of the plurality of servers (2) in the cabinet (1) in each time slot in the network architecture makes the signal after the beam combination of the beam combiner (3) not interfere with each other.

6. The network architecture of claim 1, wherein, The top mirror (8) is a fixed plane mirror or a micro-electro-mechanical system (MEMS) controllable mirror, which is used for realizing accurate guidance of the optical beam between cabinets.

7. The network architecture of any of claims 1 to 5, wherein, The network architecture supports flexible expansion of the number of cabinets and the number of servers in each cabinet without changing the existing optical fiber link or adding switching equipment.

Images