System and Method for Photonic Switching

• US 20140334818A1
• Filed: 04/07/2014
• Published: 11/13/2014
• Est. Priority Date: 05/10/2013
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Mehrvar, Hamid
• Granted Patent: US 9,654,853 B2
• Time in Patent Office: Days
• US Class Current: 398/51
• CPC Class Codes: H04J 14/0258 Wavelength identification or labelling
• CPC Class Codes: H04Q 11/0005 Switch and router aspects
• CPC Class Codes: H04Q 11/0066 Provisions for optical burst or packet networks
• CPC Class Codes: H04Q 2011/0024 using space switching
• CPC Class Codes: H04Q 2011/0039 Electrical control
• CPC Class Codes: H04Q 2011/0064 Arbitration, scheduling or medium access control aspects

Abstract

In one embodiment, a photonic switching fabric includes a first label detector configured to read a first optical label to produce a first detected label, where the first optical label corresponds to a first optical packet, and where the first optical label is in a control waveband and a switch controller configured to adjust a photonic switch in accordance with the first detected label. The photonic switching fabric also includes the photonic switch, configured to switch the first optical packet, where the first optical packet is in a payload waveband.

Claims

1. A photonic switching fabric comprising:

a first label detector configured to read a first optical label to produce a first detected label, wherein the first optical label corresponds to a first optical packet, and wherein the first optical label is in a control waveband;

a switch controller configured to adjust a photonic switch in accordance with the first detected label; and

the photonic switch, configured to switch the first optical packet, wherein the first optical packet is in a payload waveband.

2. The photonic switching fabric of claim 1, further comprising a synchronization light pulse unit coupled to the photonic switch, wherein the synchronization light pulse unit is configured to produce a synchronization light pulse, and wherein the synchronization light pulse is in the control waveband.

3. The photonic switching fabric of claim 2, further comprising a contention pulse unit coupled to the photonic switch, wherein the switch controller is configured to generate a contention signal in accordance with the first detected label, wherein the contention pulse unit is configured to generate a contention pulse in accordance with the contention signal, and wherein the contention signal is in the control waveband.

4. The photonic switching fabric of claim 2, further comprising a filter coupled between the photonic switch and the synchronization pulse unit.

5. The photonic switching fabric of claim 1, wherein first label detector comprises a wavelength division multiplexer configured to produce a plurality of control optical signals.

6. The photonic switching fabric of claim 5, further comprising an optical energy detector configured to generate a plurality of electrical bits in accordance with the plurality of optical signals.

7. The photonic switching fabric of claim 1, further comprising a second label detector configured to read a second optical label to produce a second detected label, wherein the second optical label corresponds to a second optical packet, wherein the second optical label is in the control waveband, wherein the second optical packet is in the payload waveband, wherein the switch controller is further configured to adjust the photonic switch in accordance with the second detected label, and wherein the photonic switch is further configured to switch the second optical packet.

8. The photonic switching fabric of claim 1, wherein the control waveband is a 1550 nm waveband and wherein the payload waveband is a 1310 nm waveband.

9. The photonic switching fabric of claim 1, wherein the payload waveband has four or more wavelengths.

10. The photonic switching fabric of claim 1, wherein the photonic switching fabric is configured to be coupled to a plurality of top-of-rack (TOR) switches.

11. The photonic switching fabric of claim 1, wherein the photonic switch is an optical space switch.

12. The photonic switching fabric of claim 1, wherein an integrated circuit comprises:

the photonic switch;

a multiplexer; and

a demultiplexer.

13. A method of photonic packet switching, the method comprising:

receiving, by a photonic switching fabric from a first top-of-rack (TOR) switch, a first optical label corresponding to a first optical packet, wherein the first optical label is in a control waveband;

determining whether the first TOR switch has permission to transmit the first optical packet to produce a first contention signal;

transmitting, by the photonic switching fabric to the first TOR switch, the first contention signal, wherein the first contention signal is in the control waveband; and

receiving, by the photonic switching fabric from the first TOR switch, the first optical packet when the first TOR switch has permission to transmit the first optical packet, wherein the first optical packet is in a payload waveband.

14. The method of claim 13, further comprising:

switching the first optical packet in accordance with the first optical label to produce a switched optical packet; and

transmitting, by the photonic switching fabric to a second TOR switch, the switched optical packet.

15. The method of claim 13, further comprising receiving, by the photonic switching fabric from a second TOR switch, a second optical label corresponding to a second optical packet, wherein the second optical label is in the control waveband, wherein determining whether the first TOR switch has permission to transmit the first optical packet comprises determining whether the first optical packet conflicts with the second optical packet.

16. The method of claim 15, further comprising:

transmitting, by the photonic switching fabric to the first TOR switch, a first synchronization pulse; and

transmitting, by the photonic switching fabric to the second TOR switch, a second synchronization pulse.

17. The method of claim 15, further comprising:

determining whether the second TOR switch has permission to transmit the second optical packet to produce a second contention signal; and

transmitting, by the photonic switching fabric to the second TOR switch, the second contention signal, wherein the second contention signal is in the control waveband.

18. The method of claim 13, wherein the control waveband is a 1550 nm waveband and the payload waveband is a 1310 nm waveband.

19. The method of claim 13, wherein the control waveband is a 1310 nm waveband and the payload waveband is a 1550 nm waveband.

20. A method of coordinating photonic packets, the method comprising:

transmitting, by a top-of-rack (TOR) switch to a photonic switching fabric, a control signal comprising an address of an optical packet, wherein the control signal is in a control waveband;

receiving, by the TOR switch from the photonic switching fabric, a grant indicator;

determining a transmission approval in accordance with the grant indicator; and

transmitting, by the TOR switch to the photonic switching fabric, the optical packet in accordance with the transmission approval, wherein the optical packet is in a payload waveband.

21. The method of claim 20, further comprising receiving, by the TOR switch from the photonic switching fabric, a synchronization pulse, wherein the synchronization pulse is in the control waveband.