SYSTEMS AND METHODS FOR TRANSPARENT LAYER 2 REDIRECTION TO ANY SERVICE

• US 20130007239A1
• Filed: 06/30/2011
• Published: 01/03/2013
• Est. Priority Date: 06/30/2011
• Status: Active Grant

• Current Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Original Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Inventors: Agarwal, Mugdha, Suganthi, Josephine, Annamalaisami, Saravana, Kurma, Jyotheesh Rao, Shetty, Anil, Goel, Deepak
• Granted Patent: US 8,745,266 B2
• Time in Patent Office: Days
• US Class Current: 709/223
• CPC Class Codes: H04L 45/306 Route determination based on the nature of the carried application
• CPC Class Codes: H04L 45/74 Address processing for routing
• CPC Class Codes: H04L 61/103 across network layers, e.g. resolution of network layer into physical layer addresses or address resolution protocol [ARP]
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 63/02 for separating internal from external traffic, e.g. firewalls
• CPC Class Codes: H04L 63/0815 providing single-sign-on or federations
• CPC Class Codes: H04L 65/40 Support for services or applications
• CPC Class Codes: H04L 67/563 Data redirection of data network streams

Abstract

The present solution is directed to providing, transparently and seamlessly to any client or server, layer 2 redirection of client requests to any services of a device deployed in parallel to an intermediary device An intermediary device deployed between the client and the server may intercept a client request and check if the request is to be processed by a service provided by one of the devices deployed in parallel with the intermediary device. The service may be any type and form of service or feature for processing, checking or modifying the request, including a firewall, a cache server, a encryption/decryption engine, a security device, an authentication device, an authorization device or any other type and form of service or device described herein. The intermediary device may select the machine to process the request and use layer 2 redirection to the machine. The intermediary device may change a Media Access Control (MAC) address of a destination of the request to a MAC address of the selected machine. Once the selected machine processes the request, the intermediary device may receive from this machine a response to processing the request. The intermediary device may then continue processing the request of the client responsive to the response from the machine or in response to identifying that the response to the request is from that particular selected machine. The forwarding to and processing by the parallel deployed machine may be performed seamlessly and transparently to the server and/or client.

Claims

1. A method of providing by an intermediary device access to a service deployed in parallel to the intermediary device, the method comprising:

(a) receiving, by an intermediary device deployed between a plurality of clients and one or more servers, a request from a client to access a server via a first transport layer connection;

(b) determining, by the intermediary device responsive to a policy, that the request is to be processed by a service provided by a second device, the second device deployed in parallel to the intermediary device;

(c) forwarding, by the intermediary device, the request via a second transport layer connection to the second device for processing by the service, the request modified by the intermediary device to change a Media Access Control (MAC) address of a destination of the request to a MAC address of the second device;

(d) receiving, by the intermediary device, a response to processing the request from the service of the second device;

(e) identifying, by the intermediary device, that the response is from the second device via one or more properties of a transport layer connection carrying the response; and

(f) continue processing, by the intermediary device, the request responsive to receiving the response from the second device.

2. The method of claim 1, wherein step (b) further comprises applying, by the intermediary device, the policy to content of the request.

3. The method of claim 1, wherein step (c) further comprises retaining, by the intermediary device, the destination internet protocol (IP) address of the request when forwarding the request to the second device.

4. The method of claim 1, wherein step (c) further comprises modifying, by the intermediary device, the destination MAC address of the request to the MAC address of the second device while leaving the destination internet protocol (IP) address of the request unchanged.

5. The method of claim 1, wherein step (c) further comprises using, by the intermediary device, the source IP address of the request for communicating to the second device.

6. The method of claim 1, wherein step (d) further comprises receiving from the second device the response comprising the request processed by the service.

7. The method of claim 1, wherein step (d) further comprises receiving from the second device the response comprising the request processed by the service comprising one or more of the following:

firewall service, single sign on service, Wide Area Network (WAN) acceleration service, Local Area Network (LAN) acceleration service, and a cache service.

8. The method of claim 1, wherein step (d) further comprises receiving by the intermediary device the response via one of the second transport layer connection or a third transport layer connection between the intermediary device and the second device.

9. The method of claim 1, wherein step (e) further comprises identifying by the intermediary device, that the response is from the second device via one or more data link layer properties of the transport layer connection.

10. The method of claim 1, wherein step (f) further comprises forwarding by the intermediary device the request to the server identified by the destination internet protocol (IP) address of the request.

11. A system of providing by access to a service deployed in parallel to an intermediary device, the system comprising:

an intermediary device, deployed between a plurality of clients and one or more servers, receiving a request from a client to access a server via a first transport layer connection;

a virtual server of the intermediary device determining, responsive to a policy, that the request is to be processed by a service provided by a second device, the second device deployed in parallel to the intermediary device;

wherein the intermediary device;

forwards the request via a second transport layer connection to the second device for processing by the service, the request modified by the intermediary device to change a Media Access Control (MAC) address of a destination of the request to a MAC address of the second device;

receives a response to processing the request from the service of the second device;

and identifies that the response is from the second device via one or more properties of a transport layer connection carrying the response;

wherein the virtual server continues processing the request responsive to the intermediary device receiving the response from the second device.

12. The system of claim 11, wherein the virtual server applies the policy to content of the request.

13. The system of claim 11, wherein the virtual server forwards the request to a second virtual server for communicating with the second device, the second virtual server managing the service of the second device.

14. The system of claim 11, wherein the intermediary device retains the destination internet protocol (IP) address of the request when forwarding the request to the second device.

15. The system of claim 11, wherein the intermediary device modifies the destination MAC address of the request to the MAC address of the second device while leaving the destination internet protocol (IP) address of the request unchanged.

16. The system of claim 11, wherein the intermediary device uses the source IP address of the request for communicating to the second device.

17. The system of claim 11, wherein the response comprises the request processed by the service.

18. The system of claim 11, wherein the second device provides the service comprising one or more of the following:

firewall service, single sign on service, Wide Area Network (WAN) acceleration service, Local Area Network (LAN) acceleration service, and a cache service.

19. The system of claim 11, wherein the intermediary device receives the response via one of the second transport layer connection or a third transport layer connection between the intermediary device and the second device.

20. The system of claim 11, wherein the intermediary device identifies that the response is from the second device via one or more data link layer properties of the transport layer connection.

21. The system of claim 11, wherein the intermediary device forwards the request to the server identified by the destination internet protocol (IP) address of the request.