Multi-region source routed multicast using sub-tree identifiers

1. A method comprising:

generating, by a network controller in a source routed forwarding network, a header portion comprising a hop list defining a source-routed path of a data packet, the data packet associated with a flow of data packets from a source to one or more destinations, wherein the hop list includes a sub-tree identifier, the sub-tree identifier being indicative of a multicast sub-tree; and

transmitting, by the network controller to a node in the source routed forwarding network, the generated header portion comprising the hop list defining the source-routed path of the data packet.

2. The method of claim 1 , wherein the sub-tree identifier represents a multicast sub-tree ingress node and a plurality of nodes and links forming the multicast sub-tree.

3. The method of claim 2 , wherein the sub-tree identifier is convertible by the node into a sub-tree hop list comprising the plurality of nodes and links of the multicast sub-tree.

4. The method of claim 1 , wherein the sub-tree identifier comprises:

a multi-protocol label switching (MPLS) label;

an IPv4 address;

an IPv6 address; or

a type length value (TLV) encoding.

5. A method comprising:

receiving, by a node in a source routed forwarding network, a data packet from a network controller, the data packet comprising a header, the header comprising a hop list defining a source-routed path of the data packet, the data packet associated with a flow of data packets from a source to one or more destinations, wherein the hop list includes a sub-tree identifier, the sub-tree identifier being indicative of a multicast sub-tree; and

forwarding, by the node, the data packet in accordance with the hop list.

6. The method of claim 5 , wherein the sub-tree identifier represents a multicast sub-tree ingress node and a plurality of nodes and links forming the multicast sub-tree.

7. The method of claim 6 , further comprising:

converting the sub-tree identifier into a sub-tree hop list comprising the plurality of nodes and links forming the multicast sub-tree.

8. The method of claim 6 , further comprising:

based on the hop list, transmitting the data packet to one or more of the plurality of nodes forming the multicast sub-tree.

9. The method of claim 8 , further comprising:

updating the header of the data packet before transmitting the data packet to the one or more of the plurality of nodes forming the multicast sub-tree.

10. The method of claim 5 , wherein the sub-tree identifier comprises:

a multi-protocol label switching (MPLS) label;

an IPv4 address;

an IPv6 address; or

a type length value (TLV) encoding.

11. In a source routed forwarding network, a network controller comprising:

a non-transitory memory storage comprising instructions; and

at least one processing unit in communication with the memory storage, wherein the at least one processing unit executes the instructions to:

generate, a header portion comprising a hop list defining a source-routed path of a data packet, the data packet associated with a flow of data packets from a source to one or more destinations, wherein the hop list includes a sub-tree identifier, the sub-tree identifier being indicative of a multicast sub-tree; and

transmit, to a node in the network, the generated header portion comprising the hop list defining the source-routed path of the data packet.

12. The network controller of claim 11 , wherein the sub-tree identifier represents a multicast sub-tree ingress node and a plurality of nodes and links forming the multicast sub-tree.

13. The network controller of claim 12 , wherein the sub-tree identifier is convertible by the node into a sub-tree hop list comprising the plurality of nodes and links of the multicast sub-tree.

14. The network controller of claim 11 , wherein the at least one processing unit is further configured to determine a number of multicast sub-tree ingress nodes and links and associated sub-trees in the source-routed path.

15. The network controller of claim 11 , wherein the sub-tree identifier comprises:

a multi-protocol label switching (MPLS) label;

an IPv4 address;

an IPv6 address; or

a type length value (TLV) encoding.

16. In a source routed forwarding network, a network node comprising:

a non-transitory memory storage comprising instructions; and

at least one processing unit in communication with the memory storage, wherein the at least one processing unit executes the instructions to:

receive a data packet from a network controller, the data packet comprising a header, the header comprising a hop list defining a source-routed path of the data packet, the data packet associated with a flow of data packets from a source to one or more destinations, wherein the hop list includes a sub-tree identifier, the sub-tree identifier being indicative of a multicast sub-tree; and

forward the data packet in accordance with the hop list.

17. The network node of claim 16 , wherein the sub-tree identifier represents a multicast sub-tree ingress node and a plurality of nodes and links forming the multicast sub-tree.

18. The network node of claim 17 , wherein the at least one processing unit is further configured to convert the sub-tree identifier into a sub-tree hop list comprising the plurality of nodes and links forming the multicast sub-tree.

19. The network node of claim 18 , wherein the at least one processing unit is further configured to:

based on the hop list, transmit the data packet to one or more of the plurality of nodes forming the multicast sub-tree.

20. The network node of claim 19 , wherein the at least one processing unit is further configured to:

update the header of the data packet before transmitting the data packet to the one or more of the plurality of nodes forming the multicast sub-tree.

21. The network node of claim 16 , wherein the sub-tree identifier comprises:

a multi-protocol label switching (MPLS) label;

an IPv4 address;

an IPv6 address; or

a type length value (TLV) encoding.