VIRTUAL ROUTERS FOR GMPLS NETWORKS

• US 20110255443A1
• Filed: 06/23/2011
• Published: 10/20/2011
• Est. Priority Date: 04/01/2005
• Status: Abandoned Application

• Current Assignee: RPX Clearinghouse LLC (RPX Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Ashwood-Smith, Peter, Swinkels, Gerard, Miedema, David, Skalecki, Darek
• Application Number:
  US13/167,251
• Publication Number:
  US 20110255443A1
• Time in Patent Office: Days
• US Class Current: 370/254
• 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 45/586 of virtual routers
• CPC Class Codes: H04L 45/76 Routing in software-defined topologies, e.g. routing between virtual machines

Abstract

Virtual routers that abstract photonic sub-domains are provided for GMPLS networks. A virtual router uses a link viability matrix to keep track of the set of viable connections between inputs and outputs of a photonic sub-domain. A virtual router may receive RSVP-TE signaling messages and either allocate a working input to output link pair or, if explicitly signaled, verify that the requested link is currently viable. A virtual router also advertises, in its link state updates, the current set of possible outputs for any input link. Shortest path computations can be implemented utilizing virtual routers by modifying a topology graph in accordance with the link viability matrix of the virtual router.

Claims

1. A method for determining a shortest path in a GMPLS network, the method comprising:

receiving a portion of a link viability matrix, the link viability matrix expressing, for each input of a plurality of inputs in a photonic sub-domain, whether that input has a viable connection or lacks connectivity to each particular output of a plurality of outputs in the photonic sub-domain; and

modifying a GMPLS topology graph in accordance with the received portion of the link viability matrix.

2. The method of claim 1, wherein modifying the topology graph comprises adding a node to the topology graph for each input/output in the photonic sub-domain having a viable connection to another input/output in the photonic sub-domain.

3. The method of claim 1, wherein the portion of the link viability matrix is received from a photonic communications device of the photonic sub-domain.

4. The method of claim 3, wherein the photonic communications device includes an optical controller operable to determine values in the link viability matrix.

5. The method of claim 1, wherein the portion of the link viability matrix is received over the GMPLS network.

6. The method of claim 1, wherein the method is performed at a routing element of the GMPLS network.

7. The method of claim 6, further comprising transmitting on the GMPLS network an RSVP-TE message to initiate allocation of a viable connection to the routing element.

8. The method of claim 6, further comprising transmitting on the GMPLS network an RSVP-TE message requesting a particular input/output pair to initiate verification that the particular input/output pair is a viable connection.

9. A routing element for a GMPLS network having at least one photonic sub-domain, the routing element comprising:

a receiver operable to receiving a portion of a link viability matrix, the link viability matrix expressing, for each input of a plurality of inputs in a photonic sub-domain, whether that input has a viable connection or lacks connectivity to each particular output of a plurality of outputs in the photonic sub-domain; and

GMPLS topology graph logic operable modify a GMPLS topology graph responsive to the received portion of the link viability matrix.

10. The routing element of claim 9, wherein the GMPLS topology graph logic is operable to modify the topology graph by adding a node to the topology graph for each input/output in the photonic sub-domain having a viable connection to another input/output in the photonic sub-domain.

11. The routing element of claim 9, further comprising a transmitter operable to transmit on the GMPLS network an RSVP-TE message to initiate allocation of a viable connection to the routing element.

12. The routing element of claim 9, further comprising a transmitter operable to transmit on the GMPLS network an RSVP-TE message requesting a particular input/output pair to initiate verification that the particular input/output pair is a viable connection.

13. The routing element of claim 9, wherein the receiver is operable to receive the portion of the link viability matrix from the GMPLS network.