Ultra-low latency multi-protocol optical routers for the next generation internet

• US 6,519,062 B1
• Filed: 09/01/2000
• Issued: 02/11/2003
• Est. Priority Date: 02/29/2000
• Status: Expired due to Fees

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Yoo, Sung-Joo
• Primary Examiner(s): Chan, Jason
• Assistant Examiner(s): SEDIGHIAN, REZA
• Application Number:
  US09/654,384
• Time in Patent Office: 893 Days
• Field of Search: 359/123, 359/124, 359/125, 359/127, 359/128, 359/139
• US Class Current: 398/49
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]
• CPC Class Codes: H04L 45/52 Multiprotocol routers
• 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 2011/0011 using wavelength conversion
• CPC Class Codes: H04Q 2011/0016 using wavelength multiplexing or demultiplexing
• CPC Class Codes: H04Q 2011/0032 using static wavelength routers (e.g. arrayed waveguide grating router [AWGR] )
• CPC Class Codes: H04Q 2011/0073 Provisions for forwarding or routing, e.g. lookup tables
• CPC Class Codes: H04Q 2011/0088 Signalling aspects

Abstract

An ultra-low latency optical router with a peta-bit-per-second total aggregate switching bandwidth, that will scale to a total connectivity of 1000 by 1000, and beyond by modular upgrades, that utilizes advanced optical technologies to achieve such high capacity with two to three orders of magnitude less volume and power requirements than the electrical router counter part, that serves as a universal engine to other optical routers being developed by vendors and researchers today, that can function in the context of circuit-switching, flow-switching, burst-switching, and packet-switching, that uses advanced wavelength conversion technology to effectively achieve three methods of contention resolution in the router: deflection in wavelength, deflection in space, and buffering in time, and that interfaces a local network to the Supernet.

Claims

1. An optical router, comprising:

(a) an optical wavelength router having an input and output;

(b) an input optical wavelength converter stage having an input and an output; and

(c) an output optical wavelength converter stage having an input and an output;

(d) wherein said output of said input wavelength converter stage is connected to said input of said wavelength router;

(e) wherein said input of said output wavelength converter stage is connected to said output of said wavelength router;

(f) a programmable data processor; and

(g) programming executable on said data processor for resolving switching conflicts by carrying out the operations of;

(i) receiving a data packet having an optical wavelength and a destination;

(ii) determining the preferred path to the destination from a routing table;

(iii) testing the packet to determine if the wavelength is available on the preferred path;

(iv) routing the packet on the preferred path if the wavelength is available on the preferred path;

(v) if the wavelength was not available on the preferred path, determining if the wavelength can be converted to a wavelength available on the preferred path;

(vi) if the wavelength can be converted to a wavelength available on the preferred path, converting the wavelength and routing the packet on the preferred path;

(vii) if the wavelength of the packet cannot be converted to a wavelength available on the preferred path at step (vi), determining if any wavelength is free on a loop back port;

(viii) determining if wavelength conversion is needed;

(ix) if wavelength conversion is needed, converting the wavelength, sending the packet on the loop back port, and repeating steps (iii) through (vi); and

(x) if wavelength conversion is not needed, repeating steps (iii) through (vi).

2. An optical router as recited in claim 1, wherein said wavelength router comprises an arrayed wavelength grating.

3. An optical router as recited in claim 1, wherein said wavelength router comprises a three dimensional array of arrayed wavelength gratings.

4. An optical router as recited in claim 1, wherein an input signal having a first wavelength can be converted to an output signal having a second wavelength.

5. An optical router as recited in claim 1, wherein said input wavelength converter stage comprises a plurality of wavelength converters.

6. An optical router as recited in claim 5, wherein said output wavelength converter stage comprises a plurality of wavelength converters.

7. An optical router as recited in claim 1, wherein said wavelength router includes a plurality of inputs and a plurality of outputs, and further comprising a plurality of input wavelength converter stages connected to corresponding inputs of said wavelength router, and a plurality of output wavelength converter stages connected to corresponding outputs of said wavelength router.

8. An optical router as recited in claim 1, further comprising means for routing data packets using optical labels associated with said packets.

9. An optical router as recited in claim 1, further comprising means for optical label switching, means for circuit switching, and means for packet switching.

10. An optical router as recited in claim 1, further comprising:

programming executable on said data processor for resolving switching conflicts by routing according to one or a combination of the operations of;

(xi) optical wavelength conversion;

(xii) optical time-buffering; and

(xiii) path deflection routing.

11. An optical router as recited in claim 1, wherein said programming further carries out the operations of:

(xi) if no wavelength was available at step (vii), determining a second preferred path from the routing table;

(xii) determining if a wavelength is available on the second preferred path;

(xiii) routing the packet on the second preferred path if the wavelength is available on the second preferred path;

(xiv) if the wavelength was not available on the second preferred path, determining if the wavelength can be converted to a wavelength available on the second preferred path; and

(xviii) if the wavelength can be converted to a wavelength available on the second preferred path, converting the wavelength and routing the packet on the second preferred path.

12. An optical router, comprising:

(a) an optical wavelength router having an input and output;

(b) an input optical wavelength converter stage having an input and an output; and

(c) an output optical wavelength converter stage having an input and an output;

(d) wherein said output of said input wavelength converter stage is connected to said input of said wavelength router;

(e) wherein said input of said output wavelength converter stage is connected to said output of said wavelength router;

(f) a programmable data processor; and

(g) programming executable on said data processor for resolving switching conflicts by carrying out the operations of;

(i) receiving a data packet having an optical wavelength and a destination;

(ii) determining the preferred path to the destination from a routing table;

(iii) testing the packet to determine if the wavelength is available on the preferred path;

(iv) routing the packet on the preferred path if the wavelength is available on the preferred path;

(v) if the wavelength was not available on the preferred path, determining if the wavelength can be converted to a wavelength available on the preferred path;

(vi) if the wavelength can be converted to a wavelength available on the preferred path, converting the wavelength and routing the packet on the preferred path;

(vii) if the wavelength of the packet cannot be converted to a wavelength available on the preferred path at step (vi), determining if any wavelength is free on a loop back port;

(viii) determining if wavelength conversion is needed;

(ix) if wavelength conversion is needed, converting the wavelength, sending the packet on the loop back port, and repeating steps (iii) through (vi); and

(x) if wavelength conversion is not needed, repeating steps (iii) through (vi);

(xi) if no wavelength was available at step (vii), determining a second preferred path from the routing table;

(xii) determining if a wavelength is available on the second preferred path;

(xiii) routing the packet on the second preferred path if the wavelength is available on the second preferred path;

(xiv) if the wavelength was not available on the second preferred path, determining if the wavelength can be converted to a wavelength available on the second preferred path; and

(xviii) if the wavelength can be converted to a wavelength available on the second preferred path, converting the wavelength and routing the packet on the second preferred path.

13. An optical router as recited in claim 12, wherein said wavelength router comprises an arrayed wavelength grating.

14. An optical router as recited in claim 12, wherein said wavelength router comprises a three dimensional array of arrayed wavelength gratings.

15. An optical router as recited in claim 12, wherein an input signal having a first wavelength can be converted to an output signal having a second wavelength.

16. An optical router as recited in claim 12, wherein said input wavelength converter stage comprises a plurality of wavelength converters.

17. An optical router as recited in claim 16, wherein said output wavelength converter stage comprises a plurality of wavelength converters.

18. An optical router as recited in claim 12, wherein said wavelength router includes a plurality of inputs and a plurality of outputs, and further comprising a plurality of input wavelength converter stages connected to corresponding inputs of said wavelength router, and a plurality of output wavelength converter stages connected to corresponding outputs of said wavelength router.

19. An optical router as recited in claim 12, further comprising means for routing data packets using optical labels associated with said packets.

20. An optical router as recited in claim 12, further comprising means for optical label switching, means for circuit switching, and means for packet switching.

21. An optical router as recited in claim 12, further comprising:

programming executable on said data processor for resolving switching conflicts by routing according to one or a combination of the operations of;

(xix) optical wavelength conversion;

(xx) optical time-buffering; and

(xxi) path deflection routing.

22. An optical router, comprising:

(a) an input port;

(b) a first plurality of optical wavelength converters having inputs connected to said input port;

(c) an output port;

(d) a second plurality of optical wavelength converters having outputs connected to said output port;

(e) an optical wavelength router connected between said first plurality of wavelength converters and said second plurality of wavelength converters;

(f) a programmable data processor; and

(g) programming executable on said data processor for resolving switching conflicts by carrying out the operations of;

(i) receiving a data packet having an optical wavelength and a destination;

(ii) determining a preferred path to the destination from a routing table;

(iii) testing the packet to determine if the wavelength is available on the preferred path;

(iv) routing the packet on the preferred path if the wavelength is available on the preferred path;

(v) if the wavelength was not available on the preferred path, determining if the wavelength can be converted to a wavelength available on the preferred path;

(vi) if the wavelength can be converted to a wavelength available on the preferred path, converting the wavelength and routing the packet on the preferred path;

(vii) if the wavelength of the packet cannot be converted to a wavelength available on the preferred path at step (vi), determining if any wavelength is free on a loop back port;

(viii) if a wavelength is free on the loop back port, determining if wavelength conversion is needed;

(ix) if wavelength conversion is needed, converting the wavelength, sending the packet on the loop back port, and repeating steps (iii) through (vi); and

(x) if wavelength conversion is not needed, sending the packet on the loop back port, and repeating steps (iii) through (vi).

23. An optical router as recited in claim 22, wherein said wavelength router comprises an arrayed wavelength grating.

24. An optical router as recited in claim 22, wherein said wavelength router comprises a three dimensional array of arrayed wavelength gratings.

25. An optical router as recited in claim 22, wherein an input signal having a first wavelength can be converted to an output signal having a second wavelength.

26. An optical router as recited in claim 22, wherein any wavelength input can be converted to any wavelength output.

27. An optical router as recited in claim 22, further comprising means for routing data packets using optical labels associated with said packets.

28. An optical router as recited in claim 22, further comprising means for optical label switching, means for circuit switching, and means for packet switching.

29. An optical router as recited in claim 22, further comprising:

programming executable on said data processor for resolving switching conflicts by routing according to one or a combination of the operations of;

(xi) optical wavelength conversion;

(xii) optical time-buffering; and

(xiii) path deflection routing.

30. An optical router as recited in claim 22, wherein said programming further carries out the operations of:

(xi) if no wavelength was available on the loop back port at step (vii), determining a second preferred path from the routing table;

(xii) determining if a wavelength is available on the second preferred path;

(xiii) routing the packet on the second preferred path if the wavelength is available on the second preferred path;

(xiv) if the wavelength was not available on the second preferred path, determining if the wavelength can be converted to a wavelength available on the second preferred path; and

(xv) if the wavelength can be converted to a wavelength available on the second preferred path, converting the wavelength and routing the packet on the second preferred path.

31. An optical router, comprising:

(a) an input port;

(b) a first plurality of optical wavelength converters having inputs connected to said input port;

(c) an output port;

(d) a second plurality of optical wavelength converters having outputs connected to said output port;

(e) an optical wavelength router connected between said first plurality of wavelength converters and said second plurality of wavelength converters;

(f) a programmable data processor; and

(g) programming executable on said data processor for resolving switching conflicts by carrying out the operations of;

(i) receiving a data packet having an optical wavelength and a destination;

(ii) determining a preferred path to the destination from a routing table;

(iii) testing the packet to determine if the wavelength is available on the preferred path;

(iv) routing the packet on the preferred path if the wavelength is available on the preferred path;

(v) if the wavelength was not available on the preferred path, determining if the wavelength can be converted to a wavelength available on the preferred path;

(vi) if the wavelength can be converted to a wavelength available on the preferred path, converting the wavelength and routing the packet on the preferred path;

(vii) if the wavelength of the packet cannot be converted to a wavelength available on the preferred path at step (vi), determining if any wavelength is free on a loop back port;

(viii) if a wavelength is free on the loop back port, determining if wavelength conversion is needed;

(ix) if wavelength conversion is needed, converting the wavelength, sending the packet on the loop back port, and repeating steps (iii) through (vi);

(x) if wavelength conversion is not needed, sending the packet on the loop back port, and repeating steps (iii) through (vi);

(xi) if no wavelength was available on the loop back port at step (vii), determining a second preferred path from the routing table;

(xii) determining if a wavelength is available on the second preferred path;

(xiii) routing the packet on the second preferred path if the wavelength is available on the second preferred path;

(xiv) if the wavelength was not available on the second preferred path, determining if the wavelength can be converted to a wavelength available on the second preferred path; and

(xv) if the wavelength can be converted to a wavelength available on the second preferred path, converting the wavelength and muting the packet on the second preferred path.

32. An optical router as recited in claim 31, wherein said wavelength router comprises an arrayed wavelength grating.

33. An optical router as recited in claim 31, wherein said wavelength router comprises a three dimensional array of arrayed wavelength gratings.

34. An optical router as recited in claim 31, wherein an input signal having a first wavelength can be converted to an output signal having a second wavelength.

35. An optical router as recited in claim 31, wherein any wavelength input can be converted to any wavelength output.

36. An optical router as recited in claim 31, further comprising means for routing data packets using optical labels associated with said packets.

37. An optical router as recited in claim 31, further comprising means for optical label switching, means for circuit switching, and means for packet switching.

38. An optical router as recited in claim 31, further comprising:

programming executable on said data processor for resolving switching conflicts by routing according to one or a combination of the operations of;

(xvi) optical wavelength conversion;

(xvii) optical time-buffering; and

(xviii) path deflection routing.

39. A method for resolving switching conflicts in an optical router, comprising:

(a) receiving a data packet having an optical wavelength and a destination;

(b) determining a preferred path to the destination from a routing table;

(c) testing the packet to determine if the wavelength is available on the preferred path;

(d) routing the packet on the preferred path if the wavelength is available on the preferred path;

(e) if the wavelength was not available on the preferred path, determining if the wavelength can be converted to a wavelength available on the preferred path;

(f) if the wavelength can be converted to a wavelength available on the preferred path, converting the wavelength and routing the packet on the preferred path.

(g) if the wavelength of the packet cannot be converted to a wavelength available on the preferred path at step (f), determining if any wavelength is free on a loop back port;

(h) if a wavelength is free on the loop back port, determining if wavelength conversion is needed;

(i) if wavelength conversion is needed, converting the wavelength, sending the packet on the loop back port, and repeating steps (c) through (f);

(j) if wavelength conversion is not needed, sending the packet on the loop back port, and repeating steps (c) through (f);

(k) if no wavelength was available on a loop back port at step (g), determining a second preferred path from the routing table;

(l) determining if the wavelength is available on the second preferred path;

(m) routing the packet on the second preferred path if the wavelength is available on the second preferred path;

(n) if the wavelength was not available on the second preferred path, determining if the wavelength can be converted to a wavelength available on the second preferred path;

(o) if the wavelength can be converted to a wavelength available on the second preferred path, converting the wavelength and routing the packet on the second preferred path.