Multipoint to multipoint communication over ring topologies

1. A method for assigning bandwidth in a network including nodes coupled by links arranged in a physical topology, the method comprising:

defining between the nodes logical connections associated with a data transmission service to be provided over the network, the logical connections having a connection topology different from the physical topology;

determining respective bandwidth requirements for the logical connections based on parameters of the service;

mapping the connection topology to the physical topology, so that each of the logical connections is associated with one or more links of the physical topology; and

allocating a bandwidth for the service on each of the links in response to the bandwidth requirements of the logical connections and to the mapping.

2. The method according to claim 1 , wherein the network comprises a ring network, and wherein the physical topology comprises a ring topology.

3. The method according to claim 1 , wherein the connection topology is chosen from one of a hub-and-spoke topology and a full mesh topology.

4. The method according to claim 1 , wherein the data transmission service comprises a guaranteed bandwidth service.

5. The method according to claim 1 , wherein the data transmission service comprises a class of service defined by a protocol under which the network operates.

6. The method according to claim 1 , and comprising multiplying the bandwidth by a correction factor to determine an actual bandwidth.

7. The method according to claim 1 , wherein mapping the connection topology to the physical topology comprises generating a bandwidth requirement for each of the links.

8. The method according to claim 1 , wherein parameters of the service comprise respective node-bandwidths required by each of the nodes to provide the service.

9. The method according to claim 1 , and comprising monitoring traffic generated in the network by the data transmission service, and adjusting the bandwidth in response to the traffic.

10. The method according to claim 1 , wherein the data transmission service comprises a plurality of subclasses of traffic, and wherein allocating the bandwidth comprises allocating a reserved bandwidth to one of the subclasses.

11. The method according to claim 1 , wherein allocating the bandwidth comprises comparing a mapping bandwidth determined in response to the bandwidth requirements of the logical connections and to the mapping with a full bandwidth determined by assuming all possible logical connections in the network are provided for.

12. A method for assigning bandwidth in a network including nodes coupled by links arranged in a physical topology, the method comprising:

defining between the nodes a first set of logical connections associated with a first data transmission service to be provided over the network, and a second set of logical connections associated with a second data transmission service to be provided over the network, the first set of logical connections having a first connection topology, the second set of logical connections having a second connection topology, the first and second connection topologies being different from the physical topology;

determining respective first bandwidth requirements for the first set of logical connections based on first parameters of the first data transmission service and respective second bandwidth requirements for the second set of logical connections based on second parameters of the second data transmission service;

generating a first mapping of the first connection topology to the physical topology, so that each of the first set of logical connections is associated with one or more links of the physical topology;

allocating a first bandwidth for the first data transmission service on each of the links in response to the first bandwidth requirements of the first set of logical connections and to the first mapping;

generating a second mapping of the second connection topology to the physical topology, so that each of the second set of logical connections is associated with one or more links of the physical topology;

allocating a second bandwidth for the second data transmission service on each of the links in response to the second bandwidth requirements of the second set of logical connections and to the second mapping; and

summing the first and the second bandwidths to determine a total allocation for each of the links.

13. The method according to claim 12 , wherein the network comprises a ring network, and wherein the physical topology comprises a ring topology.

14. The method according to claim 12 , wherein the first connection topology comprises a hub-and-spoke topology and the second connection topology comprises a full mesh topology.

15. The method according to claim 12 , wherein at least one of the first and second data transmission services comprises a guaranteed bandwidth service.

16. The method according to claim 12 , wherein at least one of the first and second data transmission services comprises a class of service defined by a protocol under which the network operates.

17. The method according to claim 12 , and comprising multiplying at least one of the first and second bandwidths by a correction factor to determine a corrected bandwidth.

18. The method according to claim 12 , wherein generating the first mapping comprises generating a first bandwidth requirement for each of the links, and wherein generating the second mapping comprises generating a second bandwidth requirement for each of the links.

19. The method according to claim 12 , wherein the first parameters of the first service comprise respective first node-bandwidths required by each of the nodes to provide the first service, and wherein the second parameters of the second service comprise respective second node-bandwidths required by each of the nodes to provide the second service.

20. The method according to claim 12 , and comprising monitoring traffic generated in the network by the first and second data transmission services, and adjusting the total allocation in response to the traffic.

21. The method according to claim 12 , wherein the first data transmission service comprises a plurality of subclasses of traffic, and wherein allocating the first bandwidth comprises allocating a reserved bandwidth to one of the subclasses.

22. The method according to claim 12 , wherein the first connection topology is different from the second connection topology.

23. The method according to claim 12 , wherein summing the first and the second bandwidths to determine a total allocation for each of the links comprises:

determining a first mapping bandwidth in response to the first bandwidth requirements of the first set of logical connections and to the first mapping;

determining a second mapping bandwidth in response to the second bandwidth requirements of the second set of logical connections and to the second mapping; and

comparing the first mapping bandwidth and the second mapping bandwidth with a full bandwidth determined by assuming all possible logical connections in the network are provided for.

24. A method for assigning bandwidth in a ring network including nodes coupled by links, the method comprising:

defining between the nodes a first set of logical connections associated with a first data transmission service to be provided over the network, and a second set of logical connections associated with a second data transmission service to be provided over the network, the first set of logical connections having a hub-and-spokes connection topology, the second set of logical connections having a full mesh connection topology;

determining respective first bandwidth requirements for the first set of logical connections based on first parameters of the first data transmission service and respective second bandwidth requirements for the second set of logical connections based on second parameters of the second data transmission service;

generating a first mapping of the first connection topology to the ring network, so that each of the first set of logical connections is associated with one or more links of the ring network;

determining a first bandwidth for the first data transmission service on each of the links in response to the first bandwidth requirements of the first set of logical connections and to the first mapping;

generating a second mapping of the second connection topology to the ring topology, so that each of the second set of logical connections is associated with one or more links of the ring network;

determining a second bandwidth for the second data transmission service on each of the links in response to the second bandwidth requirements of the second set of logical connections and to the second mapping;

summing the first and the second bandwidths to determine a total bandwidth for each of the links; and

allocating one of the first bandwidth, the second bandwidth, and the total bandwidth to each of the links in response to respectively providing the first service, the second service, and both services, over the network.

25. Apparatus for assigning bandwidth in a network including nodes coupled by links arranged in a physical topology, the apparatus comprising:

a controller which is adapted to:

receive a definition of logical connections between the nodes, the logical connections being associated with a data transmission service to be provided over the network, the logical connections having a connection topology different from the physical topology,

determine respective bandwidth requirements for the logical connections based on parameters of the service,

map the connection topology to the physical topology, so that each of the logical connections is associated with one or more links of the physical topology, and

allocate a bandwidth for the service on each of the links in response to the bandwidth requirements of the logical connections and to the mapping.

26. Apparatus according to claim 25 , wherein the controller is comprised in one of the nodes.

27. Apparatus according to claim 25 , wherein the controller is external to the network.

28. Apparatus for assigning bandwidth in a network including nodes coupled by links arranged in a physical topology, the apparatus comprising:

a controller which is adapted to:

receive a definition of a first set of logical connections, between the nodes, associated with a first data transmission service to be provided over the network, and a second set of logical connections, between the nodes, associated with a second data transmission service to be provided over the network, the first set of logical connections having a first connection topology, the second set of logical connections having a second connection topology, the first and second connection topologies being different from the physical topology,

determine respective first bandwidth requirements for the first set of logical connections based on first parameters of the first data transmission service and respective second bandwidth requirements for the second set of logical connections based on second parameters of the second data transmission service,

generate a first mapping of the first connection topology to the physical topology, so that each of the first set of logical connections is associated with one or more links of the physical topology,

allocate a first bandwidth for the first data transmission service on each of the links in response to the first bandwidth requirements of the first set of logical connections and to the first mapping,

generate a second mapping of the second connection topology to the physical topology, so that each of the second set of logical connections is associated with one or more links of the physical topology,

allocate a second bandwidth for the second data transmission service on each of the links in response to the second bandwidth requirements of the second set of logical connections and to the second mapping, and

sum the first and the second bandwidths to determine a total allocation for each of the links.

29. Apparatus according to claim 28 , wherein the controller is comprised in one of the nodes.

30. Apparatus according to claim 28 , wherein the controller is external to the network.