Method and apparatus for shortest path bridging of multicast traffic
Methods, system and apparatus for determining shortest path bridging (SPB) within a communications network.
1. A method of determining forwarding tree data at a node within a communications network, the method comprising:
determining, at said node, a designated node (DN) associated with a shortest path tree according to a commonly agreed mechanism;
determining, at said node, a forwarding tree comprising a set of shortest paths between said DN and respective other nodes within said communications network;
selecting at said node for inclusion in node forwarding tree data supporting said shortest path tree only those shortest paths of the forwarding tree that traverse said node; and
propagating traffic from said node based on said node forwarding tree data.
2. The method of claim 1 , wherein said method is repeated for each of a plurality of shortest path trees.
3. The method of claim 2 , wherein each of said plurality of shortest path trees comprise one of a unicast tree and a multicast tree.
4. The method of claim 2 , wherein each of said plurality of shortest path trees comprises a respective service instance.
5. The method of claim 2 , wherein a respective commonly agreed mechanism is used for each of said plurality of shortest path trees.
6. The method of claim 1 , wherein said method is performed at each of a plurality of nodes within the network, each of said nodes determining said DN associated with said shortest path tree according to said commonly agreed mechanism.
7. The method of claim 1 , wherein said node forwarding tree data is stored at said node in a Forwarding Information Base (FIB).
8. The method of claim 1 , wherein said DN comprises a lowest priority operational node.
9. The method of claim 1 , wherein the shortest path tree is built using link metrics associated with said DN.
10. The method of claim 1 , wherein the shortest path tree is built using tiebreakers associated with said DN.
11. The method of claim 1 , wherein said node forwarding tree data stored at said node comprises a *,G tree based on the shortest path tree.
12. The method of claim 1 , wherein said method is repeated at said node for each of a plurality of service instances, said node forwarding tree data including data associated with each of said plurality of service instances.
13. The method of claim 12 , wherein said node forwarding tree data stored at said node comprises, for each of said plurality of service instances, a respective *,G tree.
14. The method of claim 1 , wherein the commonly agreed mechanism comprises a system identification field.
15. The method of claim 1 , wherein the commonly agreed mechanism comprises a bridge priority field.
16. The method of claim 1 , wherein the commonly agreed mechanism comprises any existing type length value (TLV) associated with a shortest path bridging protocol.
17. The method of claim 1 , wherein the commonly agreed mechanism comprises a new type length value (TLV) introduced to a shortest path bridging protocol.
18. The method of claim 1 , wherein said selecting comprises pruning said forwarding tree to exclude ones of the shortest paths between said DN and said respective other nodes.
19. A non-transitory computer-readable storage medium storing instructions which, when executed by a computer, configure the operation of the computer to provide a method of determining forwarding tree data at a node within a communications network, the method comprising:
determining, at said node, a designated node (DN) associated with a shortest path tree according to a commonly agreed mechanism;
determining, at said node, a forwarding tree comprising a set of shortest paths between said DN and respective other nodes within said communications network;
selecting at said node for inclusion in node forwarding tree data supporting said shortest path tree only those shortest paths of the forwarding tree that traverse said node; and
propagating traffic from said node based on said node forwarding tree data.
20. A computer program product comprising a non-transitory computer-readable storage medium storing instructions which, when executed by a processor in a telecom network element, configure the operation of the telecom network element to provide a method of determining forwarding tree data at a node within a communications network, the method comprising:
determining, at said node, a designated node (DN) associated with a shortest path tree according to a commonly agreed mechanism;
determining, at said node, a forwarding tree comprising a set of shortest paths between said DN and respective other nodes within said communications network;
selecting at said node for inclusion in node forwarding tree data supporting said shortest path tree only those shortest paths of the forwarding tree that traverse said node; and
propagating traffic from said node based on said node forwarding tree data.
21. An apparatus configured to determine forwarding tree data at a node within a communications network, the apparatus comprising:
a processor and a memory communicatively connected to the processor, the processor configured to:
determine, at said node, a designated node (DN) associated with a shortest path tree according to a commonly agreed mechanism;
determine, at said node, a forwarding tree comprising a set of shortest paths between said DN and respective other nodes within said communications network;
select at said node for inclusion in node forwarding tree data supporting said shortest path tree only those shortest paths of the forwarding tree that traverse said node; and
propagate traffic from said node based on said node forwarding tree data.
22. The apparatus of claim 21 , wherein the processor is configured to determine node forwarding tree data for each of a plurality of shortest path trees.
23. The apparatus of claim 22 , wherein each of said plurality of shortest path trees comprise one of a unicast tree and a multicast tree.
24. The apparatus of claim 22 , wherein each of said plurality of shortest path trees comprises a respective service instance.
25. The apparatus of claim 22 , wherein a respective commonly agreed mechanism is used for each of said plurality of shortest path trees.
26. The apparatus of claim 21 , wherein said shortest path trees comprise one of a unicast tree and a multicast tree.
27. The apparatus of claim 21 , wherein the processor is configured to store said node forwarding tree data at said node in a Forwarding Information Base (FIB).
28. The apparatus of claim 21 , wherein said DN comprises a lowest priority operational node.
29. The apparatus of claim 21 , wherein the shortest path tree is built using link metrics associated with said DN.
30. The apparatus of claim 21 , wherein the shortest path tree is built using tiebreakers associated with said DN.
31. The apparatus of claim 21 , wherein said node forwarding tree data stored at said node comprises a *,G tree based on the shortest path tree.
32. The apparatus of claim 21 , wherein the processor is configured to determine node forwarding tree data for each of a plurality of service instances, said node forwarding tree data including data associated with each of said plurality of service instances.
33. The apparatus of claim 32 , wherein said node forwarding tree data stored at said node comprises, for each of said plurality of service instances, a respective *,G tree.
34. The apparatus of claim 21 , wherein the commonly agreed mechanism comprises a system identification field.
35. The apparatus of claim 21 , wherein the commonly agreed mechanism comprises a bridge priority field.
36. The apparatus of claim 21 , wherein the commonly agreed mechanism comprises any existing type length value (TLV) associated with a shortest path bridging protocol.
37. The apparatus of claim 21 , wherein the commonly agreed mechanism comprises a new type length value (TLV) introduced to a shortest path bridging protocol.
38. The apparatus of claim 21 , wherein, to select only those shortest paths of the forwarding tree that traverse said node, the processor is configured to:
prune said forwarding tree to exclude ones of the shortest paths between said DN and said respective other nodes.