Systems and Methods for Content Injection

• US 20090234972A1
• Filed: 03/06/2009
• Published: 09/17/2009
• Est. Priority Date: 03/07/2008
• Status: Active Grant

• Current Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Original Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Inventors: RAGHU, Jagannath, ANNAMALAISAMI, Saravana, RAJAN, Roy
• Granted Patent: US 8,850,070 B2
• Time in Patent Office: Days
• US Class Current: 709/246
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/561 Adding application-functional data or data for application control, e.g. adding metadata
• CPC Class Codes: H04L 67/564 Enhancement of application control based on intercepted application data
• CPC Class Codes: H04L 67/565 Conversion or adaptation of application format or content adding application control or application functional data H04L67/561

Abstract

The present solution is directed towards a policy-based intermediary that dynamically and flexibly injects content in responses between a client and a server based on one or more policies. The present solution addresses the challenges of injecting content in a client-server transaction. The intermediary determines when and what content to inject into a response of a client-server transaction based on a request and/or response policy. The injected content may include timestamp and/or variable tracking of different events in a client-server transaction. For example, when an intermediary appliance is deployed in a system to accelerate system performance and improve user experience, the appliance may inject content based on policy to monitor the acceleration performance of the deployed appliance.

Claims

1. A method for controlling by an intermediary via a policy engine injection of content into a response from a server to a request of a client, the method comprising the steps of:

(a) receiving, by an intermediary, a response from a server to a request of a client;

(b) determining, by a policy engine of the intermediary, the response matches a policy, the policy specifying content to insert into the response, the content identifying a variable provided by the intermediary;

(c) modifying, by the intermediary, the response to insert the content specified by the policy, the intermediary providing a value for the variable identified in the content; and

(d) transmitting, by the intermediary, the modified response to the client in response to the request.

2. The method of claim 1, comprising determining, by the intermediary, a first time of receipt of a first byte of the request, and a second time of receipt of a last byte of the request.

3. The method of claim 2, comprising providing, by the intermediary, the value of one of the first time of receipt of the request or the second time of receipt of the request for the variable identified by the content inserted in the response.

4. The method of claim 1, comprising determining, by the intermediary, a first time of transmission of a first byte of the request to the server, and a second time of transmission of a last byte of the request to the server.

5. The method of claim 4, comprising providing, by the intermediary, a value of one of the first time of transmission or the second time of transmission for the variable identified by the content inserted in the response.

6. The method of claim 1, comprising determining, by the intermediary, a first time of receipt of a first byte of the response, and a second time of receipt of a last byte of the response.

7. The method of claim 6, comprising providing, by the intermediary, the value of one of the first time of receipt of the response or the second time of receipt of the response for the variable identified by the content inserted in the response.

8. The method of claim 1, comprising determining, by the intermediary, a first time of transmission of a first byte of the response to the client, and a second time of transmission of a last byte of the response to the client.

9. The method of claim 8, comprising providing, by the intermediary, a value of one of the first time of transmission or the second time of transmission for the variable identified by the content inserted in the response.

10. The method of claim 1, comprising providing, by the intermediary, one of the following as the value of the variable:

an identifier of the intermediary, a transaction identified for the request and the response, a system uptime.

11. The method of claim 1, comprising specifying, by the policy, one of a HyperText Transfer Protocol prebody, postbody or a header as the content to insert in the response.

12. The method of claim 1, wherein step (b) comprises determining, by the policy engine, a portion of the response matches an expression of the policy.

13. The method of claim 1, wherein step (b) comprises determining, by the policy engine, one of a header or data in a payload of a network packet of the response matches an expression of the policy.

14. The method of claim 1, wherein the intermediary comprises an appliance intercepting requests and forwarding responses between the client and the server.

15. The method of claim 1, wherein the intermediary comprises an agent operating on one of the client or the server.

16. The method of claim 1 comprises determining, by the policy engine, the request matches the policy.

17. A method for controlling by an intermediary via a policy engine injection of content into a response from a server to a request of a client, the method comprising the steps of:

(a) receiving, by an intermediary, a request from a client to a server;

(b) determining, by a policy engine of the intermediary, the request matches a policy, the policy specifying content to insert into a response, the content identifying a variable provided by the intermediary;

(c) receiving, by the intermediary, the response from the server to the request of the client forwarded by the intermediary;

(d) determining, by the intermediary, the response corresponds to the request that matched the policy;

(e) modifying, by the intermediary, the response to insert the content specified by the policy, the intermediary providing a value for the variable identified in the content; and

(f) transmitting, by the intermediary, the modified response to the client in response to the request.

18. The method of claim 17, comprising determining, by the intermediary, a first time of receipt of a first byte of the request, and a second time of receipt of a last byte of the request.

19. The method of claim 18, comprising providing, by the intermediary, the value of one of the first time of receipt of the request or the second time of receipt of the request for the variable identified by the content inserted in the response.

20. The method of claim 17, comprising determining, by the intermediary, a first time of transmission of a first byte of the request to the server, and a second time of transmission of a last byte of the request to the server.

21. The method of claim 20, comprising providing, by the intermediary, a value of one of the first time of transmission or the second time of transmission for the variable identified by the content inserted in the response.

22. The method of claim 17, comprising determining, by the intermediary, a first time of receipt of a first byte of the response, and a second time of receipt of a last byte of the response.

23. The method of claim 22, comprising providing, by the intermediary, the value of one of the first time of receipt of the response or the second time of receipt of the response for the variable identified by the content inserted in the response.

24. The method of claim 17, comprising determining, by the intermediary, a first time of transmission of a first byte of the response to the client, and a second time of transmission of a last byte of the response to the client.

25. The method of claim 24, comprising providing, by the intermediary, a value of one of the first time of transmission or the second time of transmission for the variable identified by the content inserted in the response.

26. The method of claim 17, comprising providing, by the intermediary, one of the following as the value of the variable:

an identifier of the intermediary, a transaction identified for the request and the response, a system uptime.

27. The method of claim 17, comprising specifying, by the policy, one of a HyperText Transfer Protocol prebody, postbody or a header as the content to insert in the response.

28. The method of claim 17, wherein step (b) comprises determining, by the policy engine, a portion of the request matches an expression of the policy.

29. The method of claim 17, wherein step (b) comprises determining, by the policy engine, one of a header or data in a payload of a network packet of the request matches an expression of the policy.

30. The method of claim 17, wherein the intermediary comprises an appliance intercepting requests and forwarding responses between the client and the server.

31. The method of claim 17, wherein the intermediary comprises an agent operating on one of the client or the server.

32. The method of claim 17, wherein step (d) comprises determining, by the policy engine, the response matches the policy.