Methods and systems for routing packets in a VPN-client-to-VPN-client connection via an SSL/VPN network appliance

• US 8,572,721 B2
• Filed: 08/03/2006
• Issued: 10/29/2013
• Est. Priority Date: 08/03/2006
• Status: Active Grant

• Current Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Original Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Inventors: Kumar, Arkesh, Harris, James, Soni, Ajay
• Primary Examiner(s): Arani, Taghi
• Assistant Examiner(s): VICTORIA, NARCISO F
• Application Number:
  US11/462,174
• Publication Number:
  US 20080034416A1
• Time in Patent Office: 2,644 Days
• Field of Search: 726/15
• US Class Current: 726/15
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 63/0272 Virtual private networks
• CPC Class Codes: H04L 63/166 at the transport layer

Abstract

In a method and system for routing packets between clients, a packet is received from a first client connected to a secure sockets layer virtual private network (an SSL/VPN) network appliance. An identification is made, responsive to an inspection of the received packet, of i) a type of connection required for transmission of the received packet to a destination address identified by the received packet and ii) a second client connected via an SSL/VPN connection to the SSL/VPN network appliance and associated with the identified destination address. A request is made for establishment by the second client of a connection of the identified type within the SSL/VPN connection. The received packet is transmitted to the second client via the established connection of the identified type.

Claims

1. A method for routing packets between clients, the method comprising:

(a) receiving, by a device intermediary to a plurality of clients each connected to the device via a secure sockets layer virtual private network (SSL VPN) connection, a packet from a first client agent of a first client via a first SSL VPN connection with the device;

(b) identifying, by the device responsive to an inspection of the received packet, i) a type of transport layer connection required for transmission of the received packet to a destination address identified by the received packet and ii) a second client connected via a second SSL VPN connection to the device and associated with the identified destination address; and

(c) requesting establishment, by a second client agent executing on the second client, of the transport layer connection of the identified type within the second SSL VPN connection, the second client agent establishing a transport layer connection with a second application executing on the second client; and

(d) transmitting, by the device, the received packet to the second client via the established transport layer connection of the identified type, the received packet forwarded to the second application executing on the second client via the transport layer connection established between the second application and the second client agent.

2. The method of claim 1, wherein step (a) further comprises receiving, by the device, the packet via a first transport layer connection within the first SSL VPN connection.

3. The method of claim 1, wherein step (b) further comprises inspecting, by the device, the received packet.

4. The method of claim 1, wherein step (b) further comprises identifying, responsive to the inspection of the received packet, a type of transport layer connection comprising a TCP connection.

5. The method of claim 1, wherein step (b) further comprises identifying, responsive to the inspection of the received packet, a type of transport layer connection comprising a UDP connection.

6. The method of claim 1, wherein step (c) further comprises requesting, by the device, establishment by the second client of a transport layer connection of the identified type.

7. The method of claim 1, wherein step (c) comprises requesting establishment by the second client of a transport layer connection of the identified type between the second client and the device.

8. The method of claim 1, wherein step (c) further comprises establishing, by the second client, a transport layer connection of the identified type.

9. A device for routing packets between clients each connected to the device via a secure sockets layer virtual private network (SSL VPN) connection, comprising

i. a receiver receiving a packet from a first client agent of a first client over a first SSL VPN connection with the device,

ii. a packet inspector identifying, responsive to an inspection of the received packet, 1)a type of transport layer connection required for transmission of the received packet to a destination address identified by the received packet and 2) a second client connected via a second SSL VPN connection to the device and associated with the identified destination address, and

iii. a transceiver receiving a request from a second client agent executing on the second client for establishment of a transport layer connection of the identified type and transmitting the received packet to the second client over the requested transport layer connection, the second client agent establishing a transport layer connection with an application executing on the second client and forwarding the received packet to the application.

10. A system for routing packets between clients, the system comprising:

a first client of a plurality of clients, transmitting a packet;

a second client of the plurality of clients; and

a device intermediary to the plurality of clients and connected to each client via a secure sockets layer virtual private network (SSL VPN) connection, the device comprising

i. a receiver receiving the packet from a first client agent of the first client over a first SSL VPN connection,

ii. a packet inspector identifying, responsive to an inspection of the received packet,

     1) a type of transport layer connection required for transmission of the received packet to a destination address identified by the received packet and

     2) the second client, the second client connected via a second SSL VPN connection to the device and associated with the identified destination address, and

iii. a transceiver receiving a request from a second client agent executing on the second client for establishment by the second client of a transport layer connection of the identified type and transmitting the received packet to the second client over the requested transport layer connection, the second client agent establishing a transport layer connection with an application executing on the second client and forwarding the received packet to the application.

11. The system of claim 10, wherein the first client establishes the first SSL VPN connection to the device.

12. The system of claim 10, wherein the first client transmits the packet to the device over the first SSL VPN connection.

13. The system of claim 10, wherein the second client agent establishes a transport layer connection via an SSL VPN connection to the device.

14. The system of claim 10, wherein the second client further comprises an association with the destination address identified by the received packet.

15. The system of claim 10, wherein the second client agent establishes a transport layer connection of the identified type between the second client and the device.

16. The system of claim 10, wherein the second client agent establishes a transport layer connection of the identified type within an SSL VPN connection to the device.

17. A method for routing packets between clients, the method comprising:

(a) establishing, by a first client from a first network, a first secure sockets layer virtual private network (SSL VPN) connection to a second network via a device, the device intermediary to a plurality of clients each connected to the device via a SSL VPN connection;

(b) establishing, by a second client agent of a second client from a third network, a second SSL VPN connection to the second network via the device;

(c) receiving, by the device, a request from the first client via the first SSL VPN connection to connect to the second client on the second network;

(d) identifying, by the device responsive to an inspection of the received packet, i) a type of transport layer connection required for transmission of the received packet to a destination address identified by the received packet and ii) the second client on the second network associated with the identified destination address;

(e) requesting establishment, by a second client agent executing on the second client, of the transport layer connection of the identified type via the second SSL VPN connection, the second client agent establishing a transport layer connection with a second application executing on the second client; and

(f) transmitting, by the device, the received packet to the second client via the established transport layer connection of the identified type, the received packet forwarded to the second application executing on the second client via the transport layer connection established between the second application and the second client agent.