Network traffic load balancing system using IPV6 mobility headers

• US 8,819,280 B1
• Filed: 06/01/2005
• Issued: 08/26/2014
• 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): Tran, Jimmy H
• Application Number:
  US11/143,101
• Time in Patent Office: 3,373 Days
• Field of Search: 709/246, 709/226, 709/227, 709/228, 709/238, 709/241, 709/242, 709/244, 709/245, 341 50-107, 708/204
• US Class Current: 709/244
• CPC Class Codes: H04L 2463/101 applying security measures for digital rights management data processing systems or methods, specially adapted for commerce, e.g. marketing, shopping, billing, auctions or e-commerce G06Q30/00
• 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 machine-implemented method for enabling communication between nodes of a network, the method comprising:

receiving, at a server node, a first data packet that originated from a client node and that a load-balancing node forwarded to the server node after selecting the server node from among a plurality of server nodes;

in response to receiving the first data packet, the server node creating a second data packet and sending the second data packet to the client node;

wherein the second data packet contains information that will cause the client node to address to the server node a third data packet that the client node would have addressed to the load-balancing node if not for the information, the information in the second data packet instructing the client node to continue to address data packets to the server node instead of the load-balancing node for a period of time that is specified by the information;

wherein the information contained in the second data packet comprises an IPv6 Mobility Header that will cause the client node to replace an original source address of the second data packet with an address that is specified in a Home Address option of a Binding Update option contained within the IPv6 Mobility Header; and

,

wherein the method is performed at least in part by one or more processors formed by circuitry within the server node.

2. The machine-implemented method of claim 1, further comprising:

after sending the second data packet to the client node, the server node receiving the third data packet from the client node;

in response to receiving the third data packet, the server node creating a fourth data packet and sending the fourth data packet to the client node;

wherein the fourth data packet contains information that will cause the client node to address, to the server node, a fifth data packet that the client node would have addressed to the load-balancing node if not for the information, the information in the fourth data packet instructing the client node to continue to address data packets to the server node instead of the load-balancing node for a period of time that is specified by the information.

3. The machine-implemented method of claim 2, wherein a route taken by the third data packet from the client node to the server node does not include the load-balancing node.

4. The machine-implemented method of claim 2, wherein the third data packet contains a header that causes the server node to place the information within the fourth data packet.

5. The machine-implemented method of claim 1, wherein the information contained in the second data packet causes the client node to replace, in the third data packet that the client node is going to send, an Internet Protocol (IP) address that is associated with the load-balancing node with an IP address that is associated with the server node.

6. The machine-implemented method of claim 1, wherein the second data packet is an IPv6 data packet, and wherein the information in the second data packet comprises an IPv6 Mobility Header that contains a Binding Update option that specifies a Home Address option that indicates an Internet Protocol (IP) address that is associated with the load-balancing node rather than the server node.

7. The machine-implemented method of claim 1, wherein the server node is a node that the load-balancing node selected from among the plurality of server nodes due at least in part to the server node being closer to the client node than any other node in the plurality of server nodes.

8. The machine-implemented method of claim 1, wherein the first data packet contains a Transmission Control Protocol (TCP) SYN packet, and wherein the second data packet contains a TCP SYN/ACK packet.

9. The machine-implemented method of claim 1, wherein the original source address is an address of the server node and the address that is specified in the Home Address option is an address of the load-balancing node.

10. The machine-implemented method of claim 9, wherein the replacement will cause the client node to treat the second data packet as though the second data packet had originated from the load-balancing node instead of the server node.

11. The machine-implemented method of claim 1, wherein the first data packet comprises a Transmission Control Protocol (TCP) SYN packet, the second data packet comprises a TCP SYN/ACK packet, and the third data packet comprises a TCP ACK packet, wherein the first, second and third data packets are part of a TCP handshake that establishes a TCP connection between the client node and the server node.

12. The machine-implemented method of claim 1, wherein the server node is in a fixed location.

13. A system for enabling communication between nodes of a network that have circuitry forming one or more processors and memory storing processor-executable instructions, the system comprising:

a server node that receives a first data packet that originated from a client node and that a load-balancing node forwarded to the server node after selecting the server node from among a plurality of server nodes;

the server node creating, in response to receiving the first data packet, a second data packet and sending the second data packet to the client node;

wherein the second data packet contains information that will cause the client node to address to the server node a third data packet that the client would have addressed to the load-balancing node if not for the information, the information in the second data packet instructing the client node to continue to address data packets to the server node instead of the load-balancing node for a period of time that is specified by the information; and

,

wherein the information contained in the second data packet comprises an IPv6 Mobility Header that will cause the client node to replace an original source address of the second data packet with an address that is specified in a Home Address option of a Binding Update option contained within the IPv6 Mobility Header.

14. The system of claim 13, wherein:

the server node is configured to receive the third data packet from the client node;

the server node creating, in response to receiving the third data packet, a fourth data packet and sending the fourth data packet to the client node;

wherein the fourth data packet contains information that will cause the client node to address, to the server node, a fifth data packet that the client node would have addressed to the load-balancing node instead if not for the information, the information in the fourth data packet instructing the client node to continue to address data packets to the server node instead of the load-balancing node for a period of time that is specified by the information.

15. The system of claim 14, wherein a route taken by the third data packet from the client node to the server node does not include the load-balancing node.

16. The system of claim 14, wherein the third data packet contains a header that causes the server node to place the information within the fourth data packet.

17. The system of claim 13, wherein the information contained in the second data packet causes the client node to replace, in the third data packet that the client node is going to send, an Internet Protocol (IP) address that is associated with the load-balancing node with an IP address that is associated with the server node.

18. The system of claim 13, wherein the second data packet is an IPv6 data packet, and wherein the information contained in the second data packet comprises an IPv6 Mobility Header that contains a Binding Update option that specifies a Home Address option that indicates an Internet Protocol (IP) address that is associated with the load-balancing node rather than the server node.

19. The system of claim 13, wherein the server node is a node that the load-balancing node selected from among the plurality of server nodes due at least in part to the server node being closer to the client node than any other node in the plurality of server nodes.

20. The system of claim 13, wherein the first data packet contains a Transmission Control Protocol (TCP) SYN packet, and wherein the second data packet contains a TCP SYN/ACK packet.

21. The system of claim 13, wherein the original source address is an address of the server node and the address that is specified in the Home Address option is an address of the load-balancing node.

22. The system of claim 21, wherein the replacement will cause the client node to treat the second data packet as though the second data packet had originated from the load-balancing node instead of the server node.

23. The system of claim 13, wherein the first data packet comprises a Transmission Control Protocol (TCP) SYN packet, the second data packet comprises a TCP SYN/ACK packet, and the third data packet comprises a TCP ACK packet, wherein the first, second and third data packets are part of a TCP handshake that establishes a TCP connection between the client node and the server node.

24. The system of claim 13, wherein the server node is in a fixed location.

25. A machine-readable non-transitory storage medium on which is encoded one or more sequences of instructions for enabling communication between nodes of a network, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to perform steps comprising:

receiving, at a server node, a first data packet that originated from a client node and that a load-balancing node forwarded to the server node after selecting the server node from among a plurality of server nodes;

in response to receiving the first data packet, the server node creating a second data packet and sending the second data packet to the client node;

wherein the second data packet contains information that will cause the client node to address to the server node a third data packet that the client would have addressed to the load-balancing node if not for the information, the information in the second data packet instructing the client node to continue to address data packets to the server node instead of the load-balancing node for a period of time that is specified by the information; and

,

wherein the information contained in the second data packet comprises an IPv6 Mobility Header that will cause the client node to replace an original source address of the second data packet with an address that is specified in a Home Address option of a Binding Update option contained within the IPv6 Mobility Header.

26. The machine-readable non-transitory storage medium of claim 25, wherein the steps further comprise:

after sending the second data packet to the client node, the server node receiving the third packet from the client node;

in response to receiving the third data packet, the server node creating a fourth data packet and sending the fourth data packet to the client node;

wherein the fourth data packet contains information that will cause the client node to address, to the server node, a fifth data packet that the client node would have addressed to the load-balancing node if not for the information, the information in the fourth data packet instructing the client node to continue to address data packets to the server node instead of the load-balancing node for a period of time that is specified by the information.

27. The machine-readable non-transitory storage medium of claim 26, wherein a route taken by the third data packet from the client node to the server node does not include the load-balancing node.

28. The machine-readable non-transitory storage medium of claim 26, wherein the third data packet contains a header that causes the server node to place the information within the fourth data packet.

29. The machine-readable non-transitory storage medium of claim 25, wherein the information contained in the second data packet will cause the client node to replace, in a further data packet that the client node is going to send, an Internet Protocol (IP) address that is associated with the load-balancing node with an IP address that is associated with the server node.

30. The machine-readable non-transitory storage medium of claim 25, wherein the second data packet is an IPv6 data packet, and wherein the information contained in the second data packet comprises an IPv6 Mobility Header that contains a Binding Update option that specifies a Home Address option that indicates an Internet Protocol (IP) address that is associated with the load-balancing node rather than the server node.

31. The machine-readable non-transitory storage medium of claim 25, wherein the server node is a node that the load-balancing node selected from among the plurality of server nodes due at least in part to the server node being closer to the client node than any other node in the plurality of server nodes.

32. The machine-readable non-transitory storage medium of claim 25, wherein the first data packet contains a Transmission Control Protocol (TCP) SYN packet, and wherein the second data packet contains a TCP SYN/ACK packet.

33. The machine-readable non-transitory storage medium of claim 25, wherein the original source address is an address of the server node and the address that is specified in the Home Address option is an address of the load-balancing node.

34. The machine-readable non-transitory storage medium of claim 33, wherein the replacement of the original source address will cause the client node to treat the second data packet as though the second data packet had originated from the load-balancing node instead of the server node.

35. The machine-readable non-transitory storage medium of claim 25, wherein the first data packet comprises a Transmission Control Protocol (TCP) SYN packet, the second data packet comprises a TCP SYN/ACK packet, and the third data packet comprises a TCP ACK packet, wherein the first, second and third data packets are part of a TCP handshake that establishes a TCP connection between the client node and the server node.

36. The machine-readable non-transitory storage medium of claim 25, wherein the server node is in a fixed location.