Fast convergence on child link failures and weighted load balancing of aggregate ethernet/sonet bundles

1. A method implemented by a network device, the method comprising:

receiving, by the network device, probabilities associated with links associated with the network device,

each of the links being associated with a corresponding nexthop, and

each of the probabilities indicating a probability of a packet exiting the network device on a link of the links;

creating, by the network device, a distribution table based on the probabilities associated with the links;

rearranging, by the network device, values that are associated with the probabilities and are provided in the distribution table;

performing, by the network device and using information associated with the packet, a lookup in the distribution table to retrieve a particular value of the values;

selecting, by the network device, a particular nexthop based on the particular value; and

forwarding, by the network device, the packet to the particular nexthop.

2. The method of claim 1 , where the probabilities associated with the links include probabilities of the packet leaving on links of an aggregate Ethernet/SONET bundle associated with the network device.

3. The method of claim 1 , where the distribution table is provided by an application-specific integrated circuit (ASIC) of a packet forwarding engine (PFE) provided in the network device.

4. The method of claim 1 , where rearranging the values includes rearranging the values to create a randomized list of values.

5. The method of claim 1 , where the information associated with the packet includes a hash value associated with the packet.

6. The method of claim 5 , where performing the lookup in the distribution table includes:

normalizing the hash value associated with the packet; and

using the normalized hash value to perform the lookup.

7. A network device comprising:

a memory to store:

a distribution table comprising values corresponding to probabilities associated with links associated with the network device,

each of the links being associated with a corresponding nexthop, and

each of the probabilities indicating a probability of a packet exiting the network device on a link of the links, and

a list of nexthops associated with the links; and

a processor to:

receive the packet;

perform, using information associated with the packet, a lookup in the distribution table to retrieve a particular value of the values;

select a particular nexthop, of the nexthops, based on the particular value; and

forward, the packet to the particular nexthop.

8. The network device of claim 7 , where the links are of an aggregate Ethernet/SONET bundle associated with the network device.

9. The network device of claim 7 ,

where the memory is further to store:

a list of address information for the nexthops associated with the links;

where, when forwarding the packet to the nexthop, the processor is further to:

forward, using the list of address information, the packet to the nexthop.

10. The network device of claim 7 , where the information associated with the packet includes a hash value.

11. The network device of claim 10 , where, when performing the lookup, the processor is further to:

normalize the hash value, and

perform the lookup using the normalized hash value.

12. The network device of claim 7 , where the distribution table is provided by an application-specific integrated circuit (ASIC) of a packet forwarding engine (PFE) provided in the network device.

13. The network device of claim 7 , where the values in the distribution table are randomized.

14. A network device comprising:

a processor to:

receive probabilities associated with links associated with the network device,

each of the links being associated with a corresponding nexthop, and

each of the probabilities indicating a probability of a packet exiting the network device on a link of the links;

create a distribution table based on the probabilities associated with the links;

rearrange values that are associated with the probabilities and that are provided in the distribution table;

perform, using information associated with the packet, a lookup in the distribution table to retrieve a particular value of the values;

select a particular nexthop based on the particular value; and

forward the packet to the particular nexthop.

15. The network device of claim 14 , where the distribution table is provided by an application-specific integrated circuit (ASIC) of a packet forwarding engine (PFE) provided in the network device.

16. The network device of claim 14 , where the links are an aggregated bundle of links associated with the network device.

17. The network device of claim 16 , where the aggregated bundle of links comprises one of:

an aggregated Ethernet bundle of links, or

an aggregated synchronous optical networking (SONET) bundle of links.

18. The network device of claim 14 , where the information associated with the packet includes a hash value associated with the packet.

19. The network device of claim 18 , where, when performing the lookup in the distribution table, the processor is further to:

normalize the hash value associated with the packet; and

use the normalized hash value to perform the lookup.

20. The network device of claim 14 , where the values in the distribution table are randomized.