Leaking component link traffic engineering information

1. A method of operating a first packet network device, the method comprising:

advertising, via link state advertisements to a third packet network device, a route to a second packet network device, the route comprising a link aggregation supported by the first packet network device;

advertising, via traffic engineering advertisements to the third packet network device, individual bandwidth availability for a group of component links that are members of the link aggregation, the group comprising at least one component link

receiving a first request including a first label to reserve bandwidth on a first member link, of the group of component links, for traffic directed toward the first packet network device from the third packet network device along a first label-switched path;

reserving the bandwidth on the first member link;

acknowledging the reservation by directing a second request toward the third packet network device, the second request indicating a second label to be used on the first label-switched path; and

creating a first routing table entry instructing the first packet network device to accept packets labeled with the second label, swap the second label for the first label, and direct the label-swapped packets toward the second packet network device on the first member link.

2. The method of claim 1 , further comprising advertising, via traffic engineering advertisements to the third network device, bandwidth availability for the link aggregation as a whole.

3. The method of claim 2 , further comprising creating a single link state advertisement identifying both traffic engineering information for the link aggregation as a whole and traffic engineering information for at least one component link of the group of component links.

4. The method of claim 3 , wherein a traffic engineering advertisement identifying the link aggregation comprises a type-length-value field with a type corresponding to component link traffic engineering information, and a value containing at least one sub-type-length-value field describing traffic engineering information for the at least one component link.

5. The method of claim 1 , further comprising advertising, via a traffic engineering advertisement to the third packet network device, a change in unreserved bandwidth on the first member link.

6. The method of claim 1 , wherein the identity of the first member link is explicitly specified by the third packet network device.

7. The method of claim 6 , further comprising the third packet network device indicating to the first packet network device that if the requested bandwidth is not available on the explicitly specified member link, the first packet network device may satisfy the request by selecting as the first member link another link, having the requested bandwidth available, from the group of component links.

8. The method of claim 7 , further comprising the third packet network device indicating to the first packet network device that if the requested bandwidth is not available on any one link from the group of component links, but is available on the link aggregation or a smaller aggregation of the link aggregation component links, the first packet network device may satisfy the request by selecting as the first member link as the link aggregation or smaller aggregation.

9. The method of claim 7 , further comprising the first network device subsequently upgrading the label-swapped path to the explicitly specified member link when the requested bandwidth becomes available on the explicitly specified member link.

10. The method of claim 6 , wherein a setup priority for the first label-switched path is communicated to the first packet network device, the first packet network device creating the requested bandwidth on the explicitly specified member link by identifying at least one other label-switched path with bandwidth reserved on the explicitly specified member link and a hold priority lower than the setup priority of the first label-switched path, and allocating bandwidth previously reserved by the at least one other label-switched path on the explicitly specified member link to the first label-switched path.

11. The method of claim 10 , further comprising dropping the second label-switched path.

12. The method of claim 10 , further comprising moving the second label-switched path to another member link of the group of component links, the another member link having available the bandwidth reserved by the second label-switched path.

13. The method of claim 10 , further comprising moving the second label-switched path to the link aggregation or a smaller aggregation of the link aggregation component links, wherein the link aggregation or smaller aggregation has available the bandwidth reserved by the second label-switched path.

14. The method of claim 1 , wherein the third packet network device specifies at least one traffic characteristic for the label-switched path, and instructs the first packet network device to select the identity of the first member link as a link meeting the at least one traffic characteristic.

15. The method of claim 1 , wherein the first and third packet network devices are not adjacent on a network, wherein the first network device supplies the link state advertisements and traffic engineering advertisements to a fourth packet network device, and relies on the fourth packet network device to flood the link state advertisements and traffic engineering advertisements to the third packet network device.

16. The method of claim 1 , wherein the at least one component link comprises a logical grouping of a proper subset of the group of component links.