HYBRID OPTICAL/ELECTRICAL SWITCHING SYSTEM FOR DATA CENTER NETWORKS

• US 20120099863A1
• Filed: 10/25/2010
• Published: 04/26/2012
• Est. Priority Date: 10/25/2010
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Laboratories America Inc (NEC Corporation)
• Inventors: Xu, Lei, Zhang, Yueping, Singh, Atul, Jiang, Guofei, Wang, Ting
• Granted Patent: US 8,503,879 B2
• Time in Patent Office: Days
• US Class Current: 398/49
• CPC Class Codes: H04Q 11/0005 Switch and router aspects
• CPC Class Codes: H04Q 2011/0016 using wavelength multiplexing or demultiplexing
• CPC Class Codes: H04Q 2011/0035 using miscellaneous components, e.g. circulator, polarisation, acousto/thermo optical
• CPC Class Codes: H04Q 2011/0052 Interconnection of switches

Abstract

In one aspect, a system includes one or more electrical switches to transfer data in a data network; one or more optical switching groups coupled to each electrical switch, each switching group having one or more server racks, each server rack coupled to a top of rack (TOR) switch and an optical transceiver coupled to the TOR switch; and an optical switching unit (OSU) coupled to the one or more optical switching groups.

Claims

1. A system, comprising:

a. one or more electrical switches to transfer data in a data center network;

b. one or more optical switching groups coupled to each electrical switch, each switching group having one or more server racks, each server rack coupled to a top of rack (TOR) switch and an optical transceiver coupled to the TOR switch; and

c. an optical switching unit (OSU) coupled to the one or more optical switching groups.

2. The system of claim 1, comprising a channel multiplexer coupled to the optical transceiver.

3. The system of claim 2, wherein the channel multiplexer comprises an arrayed waveguide grating (AWG).

4. The system of claim 1, comprising a plurality of optical transceivers each transmitting at a different wavelength.

7. The system of claim 1, wherein a server is assigned by the TOR switch to use one optical transceiver.

8. The system of claim 1, wherein data traffic from multiple servers is aggregated and shared on one optical transceiver.

9. The system of claim 1, wherein the OSU comprises MEMS mirrors with a plurality of input and output ports.

10. The system of claim 1, wherein the OSU comprises an optical switching matrix.

11. The system of claim 10, comprising an optical power coupler (OPC) coupled to the optical transceiver to receive incoming optical signals from the server racks.

12. The system of claim 11, wherein optical signals from one optical switching group shares one OPC.

13. The system of claim 11, comprising an AWG coupled to the OPC to separate optical signals at different wavelengths to different output ports.

14. The system of claim 13, wherein the OSU directs an incoming signal on a predetermined wavelength to a corresponding optical receiver that communicates on the predetermined wavelength.

15. The system of claim 14, comprising a wavelength converter coupled to the OSU, wherein if no optical receiver on a destination server rack matches the predetermined wavelength of the incoming signal, the predetermined wavelength of the incoming signal is changed to match one of the wavelengths of the optical receivers on the destination rack, and re-directed back to the optical switching matrix for signal routing.

16. The system of claim 1, wherein the same number (N) of the input and the output ports is reserved for OSU interconnection.

5. The system of claim 5, wherein signals on different wavelengths are transmitted using one optical fiber.

6. The system of claim 5, wherein outputs from the transceivers from one rack or multiple racks share one channel multiplexer.

17. A method to communicate data in a network, comprising:

a. electrically communicating data through one or more electrical switches;

b. optically communicating data over one or more optical switching groups coupled to each electrical switch, each switching group having one or more server racks, each server rack coupled to a top of rack (TOR) switch and an optical transceiver coupled to the TOR switch; and

c. delivering data to a destination using an optical switching unit (OSU) coupled to the one or more optical switching groups.

18. The method of claim 17, comprising multiplexing data with an arrayed waveguide grating (AWG) and transmitting different wavelengths using one optical fiber, wherein data traffic from multiple servers is aggregated and shared on one optical transceiver.

19. The method of claim 17, wherein the OSU comprises an optical switching matrix, wherein the OSU directs an incoming signal on a predetermined wavelength to a corresponding optical receiver that communicates on the predetermined wavelength.

20. The method of claim 19, comprising changing the predetermined wavelength of the incoming signal to match one of the wavelengths of the optical receivers on a destination rack if no optical receiver on the destination server rack matches the predetermined wavelength of the incoming signal, and re-directing the incoming signal back to the optical switching matrix for signal routing.