Method and system for managing network traffic

• US 8,176,164 B1
• Filed: 11/18/2011
• Issued: 05/08/2012
• Est. Priority Date: 12/19/2002
• Status: Active Grant

• Current Assignee: F5 Networks, Inc. (F5 Incorporated)
• Original Assignee: F5 Networks, Inc. (F5 Incorporated)
• Inventors: Masters, Richard Roderick, Hansen, David A.
• Primary Examiner(s): JACOBS, LASHONDA T
• Application Number:
  US13/300,398
• Time in Patent Office: 172 Days
• Field of Search: 709/223, 709/224, 709/203, 709/217, 709/219, 709/225, 709/229
• US Class Current: 709/223
• CPC Class Codes: H04L 47/125 by balancing the load, e.g. traffic engineering
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers

Abstract

A system and method for directing network connections. The invention enables a network device to direct subsequent connections from a client to a server for accessing resources. A process extracts a persistence key from a received message, and employs the persistence key to identify the appropriate server. An interface is provided, enabling a user program to direct the process of extracting the persistence key. The invention also provides a way for multiple clients to persist to a common server.

Claims

1. A network device for managing communications between client devices and a plurality of server devices, comprising:

a memory device that stores executable instructions; and

a central processing unit that executes the instructions to perform actions, including;

receiving from a first client device a specified data item within a received application level communication and an other data item received as part of a secure communication protocol;

employing the specified data item and the other data item to create a first persistence key useable to direct packets from the first client device to a target;

receiving other packets from a second client device, the other packets including at least data about the first client device;

combining data from the other packets, including the data about the first client device, to create a second persistence key;

when a mapping between the second persistence key and an other target is not found, modifying fields within the second persistence key such that a mapping to the first persistence key is located; and

using the mapping of the first persistence key to identify the target, such that packets received from the second client device are directed to the same target as the first client device.

2. The network device of claim 1, wherein the combined data from the other packets from the second client device includes an identifier of the second client device, and the data about the first client device includes an identifier of the first client device.

3. The network device of claim 1, wherein the second client device includes within the received other packets an identifier of the second client device and an identifier of the first client device in a specified order such that combining the data from the other packets creates the first persistence key that is useable to direct packets from the second client device to the same target as the first client device.

4. The network device of claim 1, wherein combining data from the other packets comprises extracting data about the first client device and data about the second client device, and arranging the extracted data in a specified order such to create the first persistence key that is useable to direct packets from the second client device to the same target as the first client device.

5. The network device of claim 1, wherein receiving from a first client device further comprises processing a plurality of packets from the first client device based on a set of user defined instructions, and buffering of a number of the plurality of packets, the number of packets based on the set of user defined instructions.

6. The network device of claim 1, wherein the first persistence key is created based in part on data about the second client device.

7. A non-transitory computer storage device having computer instructions stored thereon, the computer instructions arranged to perform actions, including:

receiving from a first client device a specified data item received within an application level communication of a first plurality of packets, and an other data item received as part of a secure communication protocol;

employing the specified data item and the other data item to create a first persistence key useable to direct packets from the first client device to a target;

receiving other packets from a second client device, the other packets including at least data about the first client device;

combining data from the other packets, including the data about the first client device, to selectively create the first persistence key; and

when the first persistence key is created from the combined data, using the first persistence key to identify the target, such that packets received from the second client device are directed to the same target as the first client device.

8. The non-transitory computer storage device of claim 7, wherein combining data from the other packets comprises extracting data about the first client device and data about the second client device, and arranging the extracted data in a specified order to create the first persistence key.

9. The non-transitory computer storage device of claim 7, wherein the received other packets includes an identifier of the second client device and an identifier of the first client device in a specified order such that combining the data from the other packets creates the first persistence key.

10. The non-transitory computer storage device of claim 7, wherein to selectively create the first persistence key, further comprises:

searching for the combined data in a persistence table; and

when the combined data is not found in the persistence table, modifying the combined data and searching for the modified combined data in the persistence table.

11. The non-transitory computer storage device of claim 7, wherein the actions further comprising:

when the first persistence key is not created from combined data, manipulating the combined data to match the first persistence key.

12. The non-transitory computer storage device of claim 7, wherein receiving from the first client device further comprising controlling an amount of buffering of the first plurality of packets.

13. The non-transitory computer storage device of claim 7, wherein the first persistence key is created based in part on data about the second client device.

14. A system, comprising:

a plurality of targets useable to provide at least one response to a request; and

a network device having memory and a processor arranged to perform actions, including;

receiving from a first client device a specified data item received within a received application level communication of a first plurality of packets, and an other data item received as part of a secure communication protocol;

employing the specified data item and the other data item to create a first persistence key useable to direct packets from the first client device to a target within the plurality of targets;

receiving other packets from a second client device, the other packets including at least data about the first client device;

combining data from the other packets, including the data about the first client device, to selectively create the first persistence key; and

when the first persistence key is created from the combined data, using the first persistence key to identify the target, such that packets received from the second client device are directed to the same target as the first client device.

15. The system of claim 14, wherein combining data from the other packets comprises extracting data about the first client device and data about the second client device, and arranging the extracted data in a specified order to create the first persistence key.

16. The system of claim 14, wherein the received other packets includes an identifier of the second client device and an identifier of the first client device in a specified order such that combining the data from the other packets creates the first persistence key.

17. The system of claim 14, wherein to selectively create the first persistence key, further comprises:

searching for the combined data in a persistence table; and

when the combined data is not found in the persistence table, modifying the combined data and searching for the modified combined data in the persistence table.

18. The system of claim 14, wherein the network device performs actions further comprising:

when the first persistence key is not created from combined data, manipulating the combined data to match the first persistence key.

19. The system of claim 14, wherein receiving from the first client device further comprising controlling an amount of buffering of the first plurality of packets.

20. The system of claim 14, wherein the network device performs actions further comprising:

storing a mapping between the first persistence key and the target, such that the mapping is useable to determine when the first persistence key is created from the combined data based locating the first persistence key in the mapping using the combined data.