Hierarchical scheduler for deterministic networking

1. A method, comprising:

identifying, at a device, a set of data stream rates for a plurality of data streams;

constructing, by the device, a Huffman tree for data transmission time slots based on the set of data stream rates by sorting the data streams by respective data rates;

determining, by the device, a number of time slots assigned to a parent node in the tree; and

using, by the device, the Huffman tree to evenly distribute time slots to child nodes of the parent node to assign the time slots to the data streams by:

grouping the data rates into pairs to form a base layer of child nodes,

assigning parent nodes to each pair of data rates in the base layer that combines frequencies and data rates of the child nodes in a given pair, and

continuing grouping and assigning until a root node is formed.

2. The method as in claim 1 , further comprising:

determining a cycle size for the time slots based on the data stream rates.

3. The method as in claim 2 , wherein the set of time periods is determined using a least-squares regression.

4. The method as in claim 2 , wherein the cycle size is a multiple of the data stream rates.

5. The method as in claim 1 , wherein a cycle size of the data transmission time slots is variable.

6. The method as in claim 5 , wherein the cycle size of the data transmission time slots is a power of two.

7. The method as in claim 1 , wherein the device is a path computation element (PCE).

8. An apparatus, comprising:

one or more network interfaces to communicate with a network;

a processor coupled to the network interfaces and adapted to execute one or more processes; and

a memory configured to store a process executable by the processor, the process when executed operable to:

identify a set of data stream rates for a plurality of data streams;

construct a Huffman tree for data transmission time slots based on the set of data stream rates by sorting the data streams by respective data rates;

determine a number of time slots assigned to a parent node in the tree; and

use the Huffman tree to evenly distribute time slots to child nodes of the parent node by:

grouping the data rates into pairs to form a base layer of child nodes,

assigning parent nodes to each pair of data rates in the base layer that combines frequencies and data rates of the child nodes in a given pair, and

continuing grouping and assigning until a root node is formed.

9. The apparatus as in claim 8 , wherein the process when executed is further operable to:

determine a cycle size for the time slots based on the data stream rates.

10. The apparatus as in claim 9 , wherein the set of time periods is determined using a least-squares regression.

11. The apparatus as in claim 9 , wherein the cycle size is a multiple of the data stream rates.

12. The apparatus as in claim 8 , wherein a cycle size of the data transmission time slots is variable.

13. The apparatus as in claim 12 , wherein the cycle size of the data transmission time slots is a power of two.

14. The apparatus as in claim 8 , wherein the process when executed is further operable to:

compute a network path for the data streams.

15. A tangible, non-transitory, computer-readable media having instructions encoded thereon, the instructions when executed by a processor operable to:

identify a set of data stream rates for a plurality of data streams;

construct a Huffman tree for data transmission time slots based on the set of data stream rates by sorting the data streams by respective data rates;

determine a number of time slots assigned to a parent node in the tree; and

use the Huffman tree to evenly distribute time slots to child nodes of the parent node by:

grouping the data rates into pairs to form a base layer of child nodes,

assigning parent nodes to each pair of data rates in the base layer that combines frequencies and data rates of the child nodes in a given pair, and

continuing grouping and assigning until a root node is formed.

16. The computer-readable media as in claim 15 , wherein the instructions when executed are further operable to:

determine a cycle size for the time slots based on the data stream rates.

17. The computer-readable media as in claim 16 , wherein the set of time periods is determined using a least-squares regression.

18. The computer-readable media as in claim 16 , wherein the cycle size is a multiple of the data stream rates.

19. The computer-readable media as in claim 15 , wherein the software when executed is further operable to:

compute a network path for the data streams.

20. The computer-readable media as in claim 15 , wherein a cycle size of the data transmission time slots is variable.