Virtual inline configuration for a network device

• US 9,100,449 B2
• Filed: 07/19/2011
• Issued: 08/04/2015
• Est. Priority Date: 04/25/2006
• Status: Active Grant

• Current Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Original Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Inventors: Budhani, Haseeb, Sutter, Paul G.
• Primary Examiner(s): CHO, HONG SOL
• Application Number:
  US13/186,350
• Publication Number:
  US 20120093156A1
• Time in Patent Office: 1,477 Days
• Field of Search: 370/230, 370/252, 370/254, 370/351, 370/389, 370/392, 370/400, 370/401
• US Class Current: 1/1
• CPC Class Codes: H04L 12/56 Packet switching systems
• CPC Class Codes: H04L 67/563 Data redirection of data network streams

Abstract

A performance enhancing proxy network device is configured to operate in a virtual inline mode, in which selected network traffic is redirected to and through the network device by a router using simple routing policies. In this way, the network device can be coupled to the router in series but can still operate as if it were physically connected inline.

Claims

1. A method for processing a packet, destined to a computing device, via a network device coupled in parallel to a router, the method comprising:

receiving, by a network device having a first internet protocol (IP) address and coupled to a plurality of routers, a packet from a first router of the plurality of routers, the packet having a second destination IP address of an intended destination computing device;

identifying, by the network device, the first router of the plurality of routers as the router that diverted the packet to the network device;

preserving, by the network device, the identification of the first router of the plurality of routers as the router that diverted the packet to the network device;

processing, by the network device, the packet while preserving the second destination IP address of the packet to specify the intended destination computing device; and

transmitting, by the network device, the processed packet to the first router for transmission to the intended destination computing device, based on the preserved identification of the first router of the plurality of routers as the router that diverted the packet to the network device, the processed packet transmitted with the second destination internet protocol (IP) address of the intended destination computing device.

2. The method of claim 1, further comprising receiving, by the network device, the packet having the second destination IP address diverted by the first router via Internet Protocol (IP) layer routing without the first router replacing the second destination IP address of the packet with the first IP address of the network device.

3. The method of claim 2, further comprising diverting, by the first router, the packet according to the second destination IP address of the packet matching a policy based IP routing rule of a set of IP routing rules instead of changing the second destination IP address of the packet to the first IP address of the network device.

4. The method of claim 1, further comprising sending, by the first router, the processed packet to the computing device identified by the second destination IP address.

5. The method of claim 1, wherein preserving the identification of the first router further comprises preserving, by the network device, the selection of the first router from load balancing applied to the plurality of routers.

6. The method of claim 1, further comprising processing, by the network device, the packet by transforming the packet.

7. The method of claim 1, further comprising processing, by the network device, the packet by compressing the packet.

8. The method of claim 1, further comprising receiving, by the network device, the packet diverted by the first router based on one or more of the following:

direction, subnet or service.

9. The method of claim 1, wherein the packet is diverted to the network device without the first router changing the destination address of the packet from the second IP address of the intended destination computing device.

10. The method of claim 1, wherein the network device does not change the second destination IP address of the received packet before transmitting the processed packet to the first router.

11. The method of claim 1, wherein receiving the packet from the first router further comprises receiving the packet from the first router as a next hop from the router to the computing device.

12. The method of claim 1, wherein the network device is deployed in a virtual inline configuration.

13. A system for processing a packet, destined to a computing device, via a network device coupled in parallel to a router, the system comprising:

a network device having a first internet protocol (IP) address, coupled to a plurality of routers, the network device receiving a packet from a first router of the plurality of routers, the packet having a second destination internet protocol (IP) address of an intended destination computing device; and

wherein the network device

identifies the first router of the plurality of routers as the router that diverted the packet to the network device,

preserves the identification of the first router of the plurality of routers as the router that diverted the packet to the network device,

processes the packet while preserving the second destination IP address of the packet to specify the intended destination computing device, and

transmits the processed packet to the first router for transmission to the intended destination computing device based on the preserved identification of the first router of the plurality of routers as the router that diverted the packet to the network device, the processed packet transmitted with the second destination internet protocol (IP) address of the intended destination computing device.

14. The system of claim 13, wherein the network device receives the packet having the second destination IP address diverted by the first router via Internet Protocol (IP) layer routing without the first router replacing the second destination IP address of the packet with the first IP address of the network device.

15. The system of claim 14, wherein the first router diverts the packet according to the second destination IP address of the packet matching a policy based IP routing rule of a set of IP routing rules instead of changing the second destination IP address of the packet to the first IP address of the network device.

16. The system of claim 13, wherein the first router transmits the processed packet to the computing device identified by the second destination IP address.

17. The system of claim 13, wherein the network device preserves the identification of selection of the first router from load balancing applied to the plurality of routers.

18. The system of claim 13, wherein the network device processes the packet by transforming the packet.

19. The system of claim 13, wherein the network device processes the packet by compressing the packet.

20. The system of claim 13, wherein the network device receives the packet diverted by the first router based on one or more of the following:

direction, subnet or service.