Load balancing using IPV6 mobility features

• US 8,176,203 B1
• Filed: 10/17/2011
• Issued: 05/08/2012
• Est. Priority Date: 10/29/2004
• Status: Active Grant

• Current Assignee: Akamai Technologies, Inc.
• Original Assignee: Akamai Technologies, Inc.
• Inventors: Liu, Zaide, Day, Richard David, Swildens, Eric Sven-Johan
• Primary Examiner(s): Won, Michael
• Application Number:
  US13/275,115
• Time in Patent Office: 204 Days
• Field of Search: 709/203, 709/217, 709/227, 709/235, 709/241, 709/244, 709/246
• US Class Current: 709/238
• CPC Class Codes: H04L 2463/101 applying security measures for digital rights management
• CPC Class Codes: H04L 63/102 Entity profiles
• CPC Class Codes: H04L 63/12 Applying verification of the received information cryptographic mechanisms or cryptographic arrangements for data integrity or data verification H04L9/32

Abstract

Techniques are provided for using the mobility support features of IPv6 to allow client and server nodes to communicate without the continuing intervention of a load-balancing node that selected the server node. A load-balancing node intercepts a TCP SYN packet addressed to a virtual IP address. The load-balancing node selects a server node from among multiple server nodes, and sends the packet toward the server node. The server node sends an IPv6 packet toward the client node. The packet contains a Binding Update option that specifies the virtual IP address as a Home Address. This information causes the client node to replace destination addresses in outgoing IP packets so that packets that the client node would have sent toward the virtual IP address are sent toward the selected server node'"'"'s IP address instead. Consequently, the IP packets are routed toward the selected server node instead of the load-balancing node.

Claims

1. A method for communicating amongst a plurality of computer network nodes, the method comprising:

receiving, at a load balancing node, an IP packet from a client node that specifies at least a portion of a request from the client node;

selecting one of a plurality of server nodes to respond to the request from the client node;

with the load-balancing node, adding an IPv6 Mobility Header to the IP packet, the IPv6 Mobility Header including a binding update option that specifies an IP address associated with the load balancing node as a home address, wherein an IP address associated the client node is a care-of address; and

sending the IP packet with the IPv6 Mobility Header to the selected server node.

2. The method of claim 1, further comprising:

sending, with the server node, a different IP packet to the client node, the different IP packet containing at least a portion of a response to the request that was at least partially specified in the IP packet.

3. The method of claim 2, wherein the different IP packet includes an IPv6 Mobility Header with a binding update option that specifies the IP address associated with the load balancing node as a home address.

4. The method of claim 2, wherein the different IP packet with the IPv6 Mobility Header specifies an IP address associated with the server node as a care-of address.

5. The method of claim 2, wherein the different IP packet with the IPv6 Mobility Header is configured to cause the server node to establish a cache entry within an IP layer cache that indicates a binding between the IP address associated with the server node and the IP address associated with the load balancing node.

6. The method of claim 1, wherein the IPv6 Mobility Header is configured to cause the server node to replace a source address in the IP packet with the home address, which is the IP address associated with the load balancing node.

7. The method of claim 1, wherein the load balancing node selects the selected server node based on the contents of the IP packet.

8. The method of claim 1, wherein the load balancing node receives a plurality of IP packets from the client node and selects the selected server node based on the contents of the plurality of IP packets.

9. The method of claim 1, wherein the IPv6 Mobility Header is configured to cause the server node to establish a cache entry within an IP layer cache that indicates a binding between the IP address associated with the client node and the IP address associated with the load balancing node.

10. The method of claim 1, wherein the source address of the IP packet represents a care-of address and specifies an IP address associated with the client node.

11. The method of claim 1, wherein the request is an HTTP request.

12. A system, comprising:

a client node, a load-balancing node, and a plurality of server nodes, each comprising computer apparatus with one or more processors and a memory holding instructions that, when executed by the one or more processors, cause said nodes to operate as follows;

the client node sending an IP packet to a load-balancing node, the IP packet specifying at least a portion of a request from the client node;

the load-balancing node receiving the IP packet and selecting one of a plurality of server nodes to respond to the IP packet;

the load-balancing node adding an IPv6 Mobility Header to the IP packet, the IPv6 Mobility Header including a binding update option that specifies an IP address associated with the load balancing node as a home address, wherein an IP address associated with the client node is a care-of address, the load balancing node sending the IP packet with the IPv6 Mobility Header to the selected server node.

13. The system of claim 12, wherein the server node sends a different IP packet to the client node, the different IP packet containing at least a portion of a response to the request that was at least partially specified in the IP packet.

14. The system of claim 13, wherein the different IP packet includes an IPv6 Mobility Header with a binding update option that specifies the IP address associated with the load balancing node as a home address.

15. The system of claim 13, wherein the different IP packet with the IPv6 Mobility Header specifies an IP address associated with the server node as a care-of address.

16. The system of claim 13, wherein, in response to the different IP packet with the IPv6 Mobility Header with the binding update option received at the client node, the client node establishes a cache entry within an IP layer cache that indicates a binding between the IP address associated with the server node and the IP address associated with the load balancing node.

17. The system of claim 12, wherein, in response to the IPv6 Mobility Header, the server node replaces a source address in the IP packet with the IP address associated with the load balancing node.

18. The system of claim 12, wherein the load balancing node selects the selected server node based on the contents of the IP packet.

19. The system of claim 12, wherein the load balancing node receives a plurality of IP packets from the client node and selects the selected server node based on the contents of the plurality of IP packets.

20. The system of claim 12, wherein, in response to the IPv6 Mobility Header with the binding update option received at the server node, the server node establishes a cache entry within an IP layer cache that indicates a binding between the IP address associated with the client node and the IP address associated with the load balancing node.

21. The system of claim 12, wherein the source address of the IP packet represents a care-of address and specifies an IP address associated with the client node.

22. The system of claim 12, wherein the request is an HTTP request.