Smart ethernet edge networking system

• US 20070280117A1
• Filed: 06/02/2006
• Published: 12/06/2007
• Est. Priority Date: 06/02/2006
• Status: Active Grant

• Current Assignee: Ciena Corporation
• Original Assignee: Ciena Corporation
• Inventors: Katz, Fabio, Frank, Pablo, Smith, Brian
• Granted Patent: US 8,218,445 B2
• Time in Patent Office: Days
• US Class Current: 370/238
• CPC Class Codes: H04L 41/00 Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/12 Shortest path evaluation
• CPC Class Codes: H04L 45/124 using a combination of metrics
• CPC Class Codes: H04L 45/125 based on throughput or bandwidth
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/302 Route determination based on requested QoS

Abstract

A system is provided for selecting connection paths in a telecommunications network having a multiplicity of nodes interconnected by a multiplicity of links. The system identifies multiple constraints for connection paths through the network between source and destination nodes, and identifies paths that satisfy all of the constraints for a connection path between a selected source node and a selected destination node. A system is also provided for optimizing utilization of the resources of such a telecommunications network by establishing connection paths through the network between selected source and destination nodes, the established connection paths satisfying the constraints; for each established connection path, determining whether other connection paths exist between the selected source and destination nodes, and that satisfy the constraints; and if at least one such other connection path exists, determining whether any such other connection path is more efficient than the established connection path and, if the answer is affirmative, switching the connection from the established connection path to the most efficient other connection path.

Claims

1. A method of selecting connection paths, in a telecommunications network having a multiplicity of nodes interconnected by a multiplicity of links, comprising

identifying multiple constraints for connection paths through said network, between source and destination nodes, and

identifying paths that satisfy all of said constraints for a connection path between a selected source node and a selected destination node.

2. The method of claim 1 wherein said telecommunications network is a network that carries Ethernet services.

3. The method of claim 1 wherein said identifying step includes

selecting a node adjacent to said source node,

determining whether the inclusion of a link from said source node to said adjacent node, in a potential path from said source node to said destination node, violates any of said constraints,

adding to said potential path said link from said source node to said adjacent node, if all of said constraints are satisfied with that link added to said potential path, and

iterating said selecting, determining and adding steps for a node adjacent to the downstream node of each successive added link, until a link to said destination node has been added.

4. The method of claim 3 which includes limiting said identifying step to a prescribed time limit, and selecting each of said adjacent nodes according to a sorting function.

5. The method of claim 1 which is executed in an offline provisioning system maintained in synchronism with said network.

6. The method of claim 1 in which said constraints include network operator-specified business rules relating to at least one factor selected from the group consisting of cost minimization, resource utilization, load balancing, packet size, rules for including and excluding nodes and links based on the requested class of service, node and link attributes and utilization, and maximum cost for the class of service.

7. The method of claim 1 in which said constraints include at least one subscriber-specified requirement selected from the group consisting of class of service, bandwidth profile, quality-of-service parameters, node/link attributes and utilization, and minimum/maximum packet size per link.

8. The method of claim 1 which includes identifying multiple paths that satisfy all of said constraints for a connection path between said selected source and destination nodes, and selecting from said multiple paths both a main path and a backup connection path between said selected source and destination nodes.

9. The method of claim 8 in which said connection paths are bidirectional.

10. The method of claim 1 which identifies paths that satisfy each of said constraints individually before identifying paths that satisfy all of said constraints for a connection path between said selected source node and said selected destination node.

11. A method of selecting connection paths, in a telecommunications network having a multiplicity of nodes interconnected by a multiplicity of links, comprising

identifying multiple constraints for connection paths through said network, between source and destination nodes, selecting a node adjacent to said source node,

selecting a node adjacent to said source node according to a sorting function,

determining whether the inclusion of a link from said source node to said adjacent node, in a potential path from said source node to said destination node, violates any of said constraints,

adding to said potential path said link from said source node to said adjacent node, if all of said constraints are satisfied with that link added to said potential path, iterating said selecting, determining and adding steps for a node adjacent to the downstream node of each successive added link, until a link to said destination node has been added, and

limiting said selecting, determining and adding steps to a prescribed time limit.

12. A method of optimizing utilization of the resources of a telecommunications network having a multiplicity of nodes interconnected by a multiplicity of links, comprising

identifying multiple constraints for connection paths through said network, between source and destination nodes,

establishing connection paths through said network between selected source and destination nodes, said established connection paths satisfying said constraints,

for each established connection path, determining whether other connection paths exist between said selected source and destination nodes, and that satisfy said constraints,

if at least one such other connection path exists, determining whether any such other connection path is more efficient than the established connection path and, if the answer is affirmative, switching the connection from said established connection path to the most efficient other connection path.

13. The method of claim 12 wherein said determining and switching are executed periodically in the background.

14. The method of claim 12 wherein said determining and switching are executed in response to a manual input.

15. The method of claim 12 wherein said telecommunication network is a network that carries Ethernet services.

16. A network management system managing a telecommunications network having a multiplicity of nodes interconnected by a multiplicity of links, comprising

a database containing multiple constraints for connection paths through said network, between source and destination nodes, and

a processor programmed to identify paths that satisfy all of said constraints for a connection path between a selected source node and a selected destination node.

17. The system of claim 16 wherein said telecommunication network is a network that carries Ethernet services.

18. The system of claim 16 which includes in an offline provisioning system maintained in synchronism with said network, for establishing said multiple connection paths.

19. The system of claim 16 in which said constraints include network operator-specified business rules relating to at least one factor selected from the group consisting of cost, resource utilization, and load balancing.

20. The system of claim 16 in which said constraints include at least one subscriber-specified requirement selected from the group consisting of class of service, bandwidth profile, and quality-of-service parameters.

21. The system of claim 16 in which said paths between each pair of source and destination nodes include both a main path and a backup connection path.

22. (canceled)

23. A scalable method of selecting a connection path from a source node to a destination node in a telecommunications network having a multiplicity of nodes interconnected by a multiplicity of links, comprising

identifying at least one constraint to be satisfied by said connection path through said network, between said source and destination nodes,

for each said constraint, pre-computing a single metric that optimizes said constraint for paths from each node of said network to said destination node,

creating a list of all potential paths between said source and destination nodes,

for each of said potential paths,

computing the value of said single metric for the portion of said oath between said source node and an intermediate node in said path, and then combining that computed value with said pre-computed value for said metric for the portion of said path between said intermediate node and said destination node,

determining whether the resulting total value violates said constraint for said metric and

if the answer is affirmative, removing said path from said list of potential paths between said source and destination nodes,

if the answer is negative, repeating said computing and determining steps for another intermediate node in said path, and

selecting a connection oath for use, from among the potential paths remaining in said list, to optimize policies.

24. The method of claim A in which said computing and determining steps are repeated for multiple potential paths in said list until the expiration of a predetermined time period.

25. The method of claim A in which said computing and determining steps are repeated for each of said potential paths in said list.

26. The method of claim A in which said computing and determining steps are executed first for the node adjacent said source node in each said path, and then for successive nodes between said first node and said destination node.