Sending instructions from a service manager to forwarding agents on a need to know basis

• US 7,042,870 B1
• Filed: 02/04/2003
• Issued: 05/09/2006
• Est. Priority Date: 07/02/1999
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Albert, Mark, Tiwari, Pranav Kumar, O'Rourke, Chris, Menditto, Louis F., Howes, Richard A., Tsang, Tzu-Ming, Jordan, James A., Kersey, Edward A.
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): ABELSON, RONALD B
• Application Number:
  US10/358,414
• Time in Patent Office: 1,190 Days
• Field of Search: 370/351, 370389-390, 370/392, 370229-231, 370/235, 370/431, 370/432
• US Class Current: 370/351
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1023 based on a hash applied to IP addresses or costs
• CPC Class Codes: H04L 67/1038 Load balancing arrangements to avoid a single path through a load balancer
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]

Abstract

A system and method are described for providing instructions for forwarding packets. The method includes broadcasting a general instruction specifying a plurality of flows to a plurality of forwarding agents and receiving at a service manager a first message responsive to the general instruction indicating that a packet for a specific flow has been received by a specific forwarding agent. A specific instruction is generated at the service manager for handling the specific flow and the specific instruction for handling the specific flow is sent to the specific forwarding agent.

Claims

1. A method for providing a network service, comprising:

receiving instructions from a service manager at a forwarding agent, the instructions being generated by the service manager and being operable to indicate how packets associated with a flow and received by the forwarding agent are to be processed;

processing the packets received at the forwarding agent according to the instructions communicated by the service manager;

receiving a subsequent packet at the forwarding agent;

determining that the subsequent packet matches a criteria included in the packet handling instructions; and

processing the subsequent packet at the forwarding agent according to the packet handling instructions.

2. The method of claim 1, wherein receiving instructions from the service manager includes receiving packet handling instructions from the service manager at the forwarding agent that include processing actions determined by the service manager for one or more of the packets, the processing actions being executed by the forwarding agent.

3. The method of claim 2, wherein processing one or more of the packets at the forwarding agent according to the packet handling instructions includes translating a destination internet protocol (IP) address in a selected one or more of the packets so that the selected one or more of the packets are forwarded to a different IP address than an IP address originally included in a packet header associated with the selected one or more of the packets.

4. The method of claim 1, wherein the instructions provided by the service manager are associated with a selected one of a group consisting of:

a routing operation;

a statistics gathering operation;

a load balancing operation;

a packet modification operation;

a tunneling operation; and

a tag switching operation.

5. The method of claim 1, further comprising:

receiving multicast packet handling instructions from the service manager at a plurality of forwarding agents, the multicast packet handling instructions including one or more actions determined by the service manager for processing of one or more of the packets by one or more of the plurality of forwarding agents.

6. The method of claim 1, wherein receiving the instructions from the service manager at the forwarding agent includes receiving a wildcard affinity at the forwarding agent that identifies one or more flows to be received by the forwarding agent.

7. The method of claim 6, wherein the wildcard affinity that identifies one or more of the flows includes a selected one of a group consisting of:

a source IP address;

a destination IP address;

a source port; and

a destination port.

8. The method of claim 1, wherein the instructions include a selected instruction that is stored at the forwarding agent until a forwarding agent expiration interval expires, the selected instruction being stored at the service manager until a service manager expiration interval expires, and wherein the service manager expiration interval is greater than the forwarding agent expiration interval.

9. The method of claim 8, wherein the service manager expiration interval is reset when the service manager receives a message from the forwarding agent indicating that a packet matching one or more of the instructions has been received by the forwarding agent.

10. A forwarding agent, comprising:

a service manager receiving interface for receiving instructions from a service manager specifying actions to be performed for server designated packets;

a service manager sending interface for communicating one or more packets to the service manager;

a network packet receiving interface for receiving one or more packets from a network;

a network packet forwarding interface for forwarding one or more packets to the network;

a processor for performing the specified actions on the server designated packets; and

a service manager instruction storage element operable to store the instructions, wherein the storage element is operable to store one or more affinities that identify one or more flows that may be selected for processing by the service manager.

11. The forwarding agent of claim 10, wherein one or more of the affinities include a selected one or more of a source internet protocol (IP) address, a destination IP address, a source port, and a destination port.

12. The forwarding agent of claim 10, wherein the instructions include a selected instruction that is stored at the forwarding agent until a forwarding agent expiration interval expires, the selected instruction being stored at the service manager until a service manager expiration interval expires, and wherein the service manager expiration interval is greater than the forwarding agent expiration interval.

13. The forwarding agent of claim 10, wherein the forwarding agent includes a decision-making capability that is related to one or more network parameters associated with one or more packets, the network parameters being selected from the group consisting of:

load balancing;

caching; and

security.

14. The forwarding agent of claim 10, wherein the forwarding agent receives a time to live parameter associated with a communication between the forwarding agent and the service manager.

15. The forwarding agent of claim 14, wherein the forwarding agent stores the communication for a time period designated by the time to live parameter and the processor deletes the communication after the time to live parameter has expired.

16. The forwarding agent of claim 10, wherein the forwarding agent is included in a selected one of a group consisting of:

a switch;

a load balancer; and

a router.

17. A system for providing a network service, comprising:

means for receiving instructions from a service manager, the instructions being generated by the service manager and being operable to indicate how packets associated with a flow are to be processed;

means for processing the packets according to the instructions communicated by the service manager;

means for receiving a subsequent packet;

means for determining that the subsequent packet matches a criteria included in the packet handling instructions; and

means for processing the subsequent packet according to the packet handling instructions.

18. The system of claim 17, wherein receiving instructions from the service manager includes receiving packet handling instructions from the service manager that include processing actions determined by the service manager for one or more of the packets.

19. The system of claim 18, wherein processing one or more of the packets according to the packet handling instructions includes translating a destination internet protocol (IP) address in a selected one or more of the packets so that the selected one or more of the packets are forwarded to a different IP address than an IP address originally included in a packet header associated with the selected one or more of the packets.

20. The system of claim 17, wherein receiving the instructions from the service manager includes receiving a wildcard affinity that identifies one or more flows to be received.

21. A computer readable medium for providing a network service, the computer readable medium comprising code operable to:

receive instructions from a service manager, the instructions being generated by the service manager and being operable to indicate how packets associated with a flow and are to be processed;

process the packets according to the instructions communicated by the service manager;

receive a subsequent packet;

determine that the subsequent packet matches a criteria included in the packet handling instructions; and

process the subsequent packet according to the packet handling instructions.

22. The medium of claim 21, wherein receiving instructions from the service manager includes receiving packet handling instructions from the service manager that include processing actions determined by the service manager for one or more of the packets.

23. The medium of claim 21, wherein processing one or more of the packets according to the packet handling instructions includes translating a destination internet protocol (IP) address in a selected one or more of the packets so that the selected one or more of the packets are forwarded to a different IP address than an IP address originally included in a packet header associated with the selected one or more of the packets.

24. The medium of claim 21, wherein receiving the instructions from the service manager includes receiving a wildcard affinity that identifies one or more flows to be received.