Combining stateless and stateful server load balancing

• US 9,906,591 B2
• Filed: 02/04/2016
• Issued: 02/27/2018
• Est. Priority Date: 10/24/2011
• Status: Active Grant

• Current Assignee: A10 Networks Incorporated
• Original Assignee: A10 Networks Incorporated
• Inventors: Jalan, Rajkumar, Xu, Feilong, Kannan, Lalgudi Narayanan, Szeto, Ronald Wai Lun
• Primary Examiner(s): O CONNOR, BRIAN T
• Application Number:
  US15/016,097
• Publication Number:
  US 20160156708A1
• Time in Patent Office: 754 Days
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 67/10 in which an application is distributed across nodes in the network software deployment G06F8/60; multiprogramming arrangements G06F9/46
• CPC Class Codes: H04L 67/1027 Persistence of sessions during load balancing
• CPC Class Codes: H04L 67/142 Managing session states for stateless protocols; Signalling session states; State transitions; Keeping-state mechanisms
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 67/564 Enhancement of application control based on intercepted application data

Abstract

The processing of data packets sent over a communication session between a host and a server by a service gateway includes processing a data packet using a current hybrid-stateful or hybrid-stateless processing method. The processing then checks whether a hybrid-stateless or hybrid-stateful condition is satisfied. When one of the sets of conditions is satisfied, the process includes changing from a hybrid-stateful to a hybrid-stateless processing method, or vice versa, for a subsequently received data packet. If the conditions are not satisfied, the process continues as originally structured.

Claims

1. A method for processing data packets sent over a communication session between a host and a server by a service gateway, comprising:

processing a data packet using a hybrid-stateful processing method by the service gateway;

checking by the service gateway whether a hybrid-stateless condition is satisfied;

in response to determining that the hybrid-stateless condition is satisfied, changing to a hybrid-stateless processing method for a subsequently received data packet by the service gateway, the service gateway maintaining a session table and a service mapping table in storage; and

in response to determining that the hybrid-stateless condition is not satisfied, processing the subsequently received data packet using the hybrid-stateful processing method by the service gateway.

2. The method of claim 1, wherein the checking by the service gateway whether the hybrid-stateless condition is satisfied comprises:

comparing a time duration stored in memory against a predetermined time duration by the service gateway;

determining whether the time duration stored in memory exceeds the predetermined time duration;

in response to determining that the time duration stored in memory exceeds the predetermined time duration, determining by the service gateway that the hybrid-stateless condition is satisfied; and

in response to determining that the time duration stored in memory does not exceed the predetermined time duration, determining by the service gateway that the hybrid-stateless condition is not satisfied.

3. The method of claim 1, wherein the checking by the service gateway whether a hybrid-stateless condition is satisfied comprises receiving from an administrator the hybrid-stateless condition by the service gateway.

4. The method of claim 3, wherein the administrator comprises:

a human operator;

a network management system;

or

a storage medium storing the hybrid-stateless condition.

5. The method of claim 1, wherein the hybrid-stateless condition comprises a predetermined session rate, wherein the checking by the service gateway whether the hybrid-stateless condition is satisfied comprises:

calculating a session rate for a plurality of communication sessions received by the service gateway;

determining whether the calculated session rate is greater than or equals the predetermined session rate by the service gateway;

in response to determining that the calculated session rate is greater than or equals the predetermined session rate, determining by the service gateway that the hybrid-stateless condition is satisfied; and

in response to determining that the calculated session rate is less than the predetermined session rate, determining by the service gateway that the hybrid-stateless condition is not satisfied.

6. The method of claim 5, wherein the calculated session rate comprises:

a difference between a count of received service requests and a count of received service termination requests over a predetermined period of time or

a count of service requests over the predetermined period of time.

7. The method of claim 1, wherein the hybrid-stateless condition comprises a predetermined session table utilization, wherein the checking by the service gateway whether a hybrid-stateless condition is satisfied comprises:

counting a number of stored session entries in the session table by the service gateway;

determining whether the number of stored session entries exceeds or is equal to the predetermined session table utilization by the service gateway;

in response to determining that the number of stored session entries exceeds or is equal to the predetermined session table utilization, determining by the service gateway that the hybrid-stateless condition is satisfied; and

in response to determining that the number of stored session entries does not exceed the predetermined session table utilization, determining by the service gateway that the hybrid-stateless condition is not satisfied.

8. A system, comprising:

a service gateway comprising a processor and a computer readable storage medium having computer readable program code embodied therewith, the computer readable program code configured to;

process a data packet using a hybrid-stateless processing method, the hybrid-stateless processing method utilizing a session table and service mapping table at the service gateway;

check whether a hybrid-stateful condition is satisfied;

in response to determining that the hybrid-stateful condition is satisfied, change to a hybrid-stateful processing method for a subsequently received data packet; and

in response to determining that the hybrid-stateful condition is not satisfied, process the subsequently received data packet using the hybrid-stateful processing method.

9. The system of claim 8, wherein the check whether a hybrid-stateful condition is satisfied comprises:

compare a time duration stored in memory against a predetermined time duration by the service gateway;

determine whether the time duration stored in memory exceeds the predetermined time duration;

in response to determining that the time duration stored in memory exceeds the predetermined time duration, determine by the service gateway that the hybrid-stateful condition is satisfied; and

in response to determining that the time duration stored in memory does not exceed the predetermined time duration, determine by the service gateway that the hybrid-stateful condition is not satisfied.

10. The system of claim 8, wherein the check whether a hybrid-stateful condition is satisfied comprises receiving from an administrator the hybrid-stateful condition by the service gateway.

11. The system of claim 10, wherein the administrator comprises:

a human operator;

a network management system;

or

a storage medium storing the hybrid-stateful condition.

12. A method for processing data packets sent over a communication session between a host and a server by a service gateway, comprising:

processing a data packet using a hybrid-stateless processing method by the service gateway, the service gateway maintaining a session table and a service mapping table in storage;

checking by the service gateway whether a hybrid-stateful condition is satisfied;

in response to determining that the hybrid-stateful condition is satisfied, changing to a hybrid-stateful processing method for a subsequently received data packet by the service gateway; and

in response to determining that the hybrid-stateful condition is not satisfied, processing the subsequently received data packet using the hybrid-stateless processing method by the service gateway.

13. The method of claim 12, wherein the checking by the service gateway whether the hybrid-stateful condition is satisfied comprises:

comparing a time duration stored in memory against a predetermined time duration by the service gateway;

determining whether the time duration stored in memory exceeds the predetermined time duration;

in response to determining that the time duration stored in memory exceeds the predetermined time duration, determining by the service gateway that the hybrid-stateful condition is satisfied; and

in response to determining that the time duration stored in memory does not exceed the predetermined time duration, determining by the service gateway that the hybrid-stateful condition is not satisfied.

14. The method of claim 12, wherein the hybrid-stateful condition comprises a predetermined session rate, wherein the checking by the service gateway whether the hybrid-stateful condition is satisfied comprises:

calculating a session rate for a plurality of communication sessions received by the service gateway;

determining whether the calculated session rate is less than the predetermined session rate by the service gateway;

in response to determining that the calculated session rate is less than the predetermined session rate, determining by the service gateway that the hybrid-stateful condition is satisfied; and

in response to determining that the calculated session rate is greater than or equals the predetermined session rate, determining by the service gateway that the hybrid-stateful condition is not satisfied.

15. The method of claim 14, wherein the calculated session rate comprises:

a difference between a count of received service requests and a count of received service termination requests over a predetermined period of time or

a count of service requests over the predetermined period of time.

16. The method of claim 12, wherein the hybrid-stateful condition comprises a predetermined session table utilization, wherein the checking by the service gateway whether a hybrid-stateful condition is satisfied comprises:

counting a number of stored session entries in the session table by the service gateway;

determining whether the number of stored session entries does not exceed the predetermined session table utilization by the service gateway;

in response to determining that the number of stored session entries does not exceed the predetermined session table utilization, determining by the service gateway that the hybrid-stateful condition is satisfied; and

in response to determining that the number of stored session entries exceeds the predetermined session table utilization, determining by the service gateway that the hybrid-stateful condition is not satisfied.

17. The method of claim 12, wherein the checking by the service gateway whether the hybrid-stateful condition is satisfied comprises:

comparing a time duration stored in memory against a predetermined time duration by the service gateway;

determining whether the time duration stored in memory exceeds the predetermined time duration;

in response to determining that the time duration stored in memory exceeds the predetermined time duration, determining by the service gateway that the hybrid-stateful condition is satisfied; and

in response to determining that the time duration stored in memory does not exceed the predetermined time duration, determining by the service gateway that the hybrid-stateful condition is not satisfied.

18. The method of claim 12, wherein the checking by the service gateway whether a hybrid-stateful condition is satisfied comprises receiving from an administrator the hybrid-stateful condition by the service gateway.

19. The method of claim 18, wherein the administrator comprises:

a human operator;

a network management system;

or

a storage medium storing the hybrid-stateful condition.