Dynamic bandwidth management responsive to access link state in redundant network topologies

• US 7,324,553 B1
• Filed: 09/30/2003
• Issued: 01/29/2008
• Est. Priority Date: 09/30/2003
• Status: Active Grant

• Current Assignee: CA, Inc. (d/b/a CA Technologies) (Broadcom, Inc.)
• Original Assignee: Packeteer Incorporated (Gen Digital Inc.)
• Inventors: Jacobson, David, Riddle, Guy, Varier, Roopesh R.
• Primary Examiner(s): NGUYEN, HANH N
• Application Number:
  US10/676,631
• Time in Patent Office: 1,582 Days
• Field of Search: 370/229, 370/230, 370/231, 370/234, 370/235, 370/468, 370/395.1, 370/395.4, 370/420, 709/223, 709/225, 709/226, 709/229, 709/232
• US Class Current: 370/468
• CPC Class Codes: H04L 41/0213 Standardised network management protocols, e.g. simple network management protocol [SNMP]
• CPC Class Codes: H04L 41/0803 Configuration setting
• CPC Class Codes: H04L 41/0896 Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities flow or congestion control using dynamic resource allocation, e.g. in-call renegotiation, H04L47/76
• CPC Class Codes: H04L 43/00 Arrangements for monitoring or testing data switching networks
• CPC Class Codes: H04L 43/0882 Utilisation of link capacity
• CPC Class Codes: H04L 43/20 the monitoring system or the monitored elements being virtualised, abstracted or software-defined entities, e.g. SDN or NFV
• CPC Class Codes: H04L 45/38 Flow based routing
• CPC Class Codes: H04L 45/70 Routing based on monitoring results
• CPC Class Codes: H04L 47/2441 relying on flow classification, e.g. using integrated services [IntServ]

Abstract

Methods, apparatuses and systems allowing for dynamic bandwidth management schemes responsive to the state of a plurality of access links in redundant network topologies. In one embodiment, the present invention provides a bandwidth management device that periodically queries routing systems associated with access links, conceptually grouped into a virtual access link, to monitor that load of the access links and, depending on the detected load, adjust the configuration of the bandwidth management device to avoid overloading one or more of the access links. Embodiments of the present invention increases network efficiency and help network traffic to flow more smoothly with higher throughput. In one embodiment, the dynamic link control functionality is invoked when any given access link reaches a threshold capacity level. Assuming that network traffic will scale in the same ratio as presently observed, the present invention calculates the maximum traffic that can be let through so that no network interface or access link is overloaded.

Claims

1. A method facilitating bandwidth management across a plurality of access links, comprising

monitoring bandwidth utilization at a plurality of interfaces in at least one routing system, wherein the plurality of interfaces are operably connected to respective access links;

selecting an interface of the plurality of interfaces having the highest bandwidth utilization relative to a corresponding bandwidth capacity of the selected interface;

computing a scaling factor comprising the ratio of the bandwidth capacity to the bandwidth utilization of the selected interface; and

computing a virtual bandwidth limit by multiplying the scaling factor by the aggregate bandwidth utilization detected across the plurality of interfaces.

2. The method of claim 1 further comprising:

configuring a bandwidth management device to enforce the virtual bandwidth limit across data flows traversing the interfaces, wherein the bandwidth management device is operably connected to a communication path between a network and the access links.

3. The method of claim 1 wherein the bandwidth utilization is inbound bandwidth utilization and the virtual bandwidth limit is an inbound virtual bandwidth limit.

4. The method of claim 1 wherein the bandwidth utilization is outbound bandwidth utilization and the virtual bandwidth limit is an outbound virtual bandwidth limit.

5. The method of claim 1 further comprising

comparing the aggregate bandwidth utilization observed at the plurality of interfaces to the aggregate bandwidth utilization observed at a bandwidth management device operably connected to a communication path between a network and the access links.

6. The method of claim 5 further comprising

adjusting the virtual bandwidth limit based on the difference between the aggregate bandwidth utilization observed at the plurality of interfaces to the aggregate bandwidth utilization observed at a bandwidth management device operably connected to a communication path between the network and the access links.

7. The method of claim 5 further comprising

reducing the virtual bandwidth limit if the aggregate bandwidth utilization observed at the plurality of interfaces is greater than the aggregate bandwidth utilization observed at a bandwidth management device operably connected to a communication path between the network and the access links.

8. The method of claim 5 further comprising

increasing the virtual bandwidth limit if the aggregate bandwidth utilization observed at the plurality of interfaces is less than the aggregate bandwidth utilization observed at a bandwidth management device operably connected to a communication path between the network and the access links.

9. The method of claim 1 further comprising

comparing the computed virtual bandwidth limit to a virtual bandwidth limit currently configured on a bandwidth management device, wherein the bandwidth management device is operably connected to a communication path between a network and the access links;

and

configuring a bandwidth management device to implement the computed virtual bandwidth limit, if the difference between the computed virtual bandwidth limit and the currently configured virtual bandwidth limit does not exceed a threshold value.

10. In a computer network environment comprising plurality of access links operably connected to respective interfaces of at least one routing system, wherein the plurality of interfaces are associated with a virtual access link, a method preventing overloading any of the interfaces, the method comprising

monitoring bandwidth utilization at the interfaces associated with the plurality of access links;

selecting an interface of the plurality of interfaces having the highest bandwidth utilization relative to a corresponding bandwidth capacity of the selected interface;

computing a scaling factor comprising the ratio of the bandwidth capacity to the bandwidth utilization of the selected interface; and

computing a virtual bandwidth limit for the virtual access link by multiplying the scaling factor by the aggregate bandwidth utilization detected across the plurality of interfaces; and

utilizing the computed virtual bandwidth limit in controlling data flows encountered at the plurality of interfaces associated with the virtual access link.

11. The method of claim 10 wherein the monitored bandwidth utilization is the inbound bandwidth utilization at the interfaces;

and wherein the bandwidth limit is an inbound bandwidth limit.

12. The method of claim 10 wherein the monitored bandwidth utilization is the outbound bandwidth utilization at the interfaces;

and wherein the bandwidth limit is an outbound bandwidth limit.

13. A data flow control device operative to prevent overloading any given interface in a plurality of interfaces, wherein the plurality of interfaces are associated with a virtual access link, comprising

a link monitoring module operative to

monitor bandwidth utilization at a plurality of interfaces associated with at least one routing system;

and

compute a bandwidth limit for the virtual access link by;

selecting an interface of the plurality of interfaces having the highest bandwidth utilization relative to a corresponding bandwidth capacity of the selected interface;

computing a scaling factor comprising the ratio of the bandwidth capacity to the bandwidth utilization of the selected interface; and

multiplying the scaling factor by the aggregate bandwidth utilization detected across the plurality of interfaces; and

a flow control module operative to enforce the bandwidth limit in controlling data flows encountered at the plurality of interfaces associated with the virtual access link.

14. The data flow control device of claim 13 wherein the bandwidth utilization is the inbound bandwidth utilization observed at the plurality of interfaces, and the bandwidth limit is an inbound bandwidth limit.

15. The data flow control device of claim 13 wherein the bandwidth utilization is the outbound bandwidth utilization observed at the plurality of interfaces, and the bandwidth limit is an outbound bandwidth limit.

16. The data flow control device of claim 13 wherein the bandwidth utilization is based on the exponential weighted moving average of the inbound bandwidth utilization observed at the plurality of interfaces, and the bandwidth limit is an inbound bandwidth limit.

17. The data flow control device of claim 13 wherein the bandwidth utilization is based on the exponential weighted moving average of the outbound bandwidth utilization observed at the plurality of interfaces, and the bandwidth limit is an outbound bandwidth limit.

18. The data flow control device of claim 13 further comprising

a traffic classification database operative to associate traffic classes to data flows;

and wherein the flow control module is operative to apply disparate bandwidth utilization policies to data flows depending on the respective traffic classes associated with the data flows.

19. A system operative to prevent overloading any given interface in a plurality of interfaces, wherein the plurality of interfaces are associated with a virtual access link, comprising

a routing system operative to route data packets received at a given interface;

wherein the routing system comprises at least a first, second and third interface;

wherein the first and second interfaces are respectively coupled to first and second access links; and

a data flow control device operatively connected to the routing system via the third interface;

wherein the data flow control device comprises;

a link monitoring module operative to

monitor bandwidth utilization at the first and second interfaces; and

compute a bandwidth limit for the virtual access link by;

selecting an interface of the plurality of interfaces having the highest bandwidth utilization relative to a corresponding bandwidth capacity of the selected interface;

computing a scaling factor comprising the ratio of the bandwidth capacity to the bandwidth utilization of the selected interface; and

multiplying the scaling factor by the aggregate bandwidth utilization detected across the plurality of interface; and

a flow control module operative to apply the bandwidth limit in controlling data flows traversing the first and second access links.

20. The system of claim 19 wherein the bandwidth utilization is the inbound bandwidth utilization observed at the first and second interfaces, and the bandwidth limit is an inbound bandwidth limit.

21. The system of claim 19 wherein the bandwidth utilization is the outbound bandwidth utilization observed at the first and second interfaces, and the bandwidth limit is an outbound bandwidth limit.