Systems and methods for communicating a lossy protocol via a lossless protocol

• US 8,634,420 B2
• Filed: 05/25/2010
• Issued: 01/21/2014
• Est. Priority Date: 07/23/2004
• Status: Active Grant

• Current Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Original Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Inventors: Rao, Goutham P., Rodriguez, Robert A., Brueggemann, Eric R.
• Primary Examiner(s): Elpenord, Candal
• Application Number:
  US12/787,231
• Publication Number:
  US 20100232429A1
• Time in Patent Office: 1,337 Days
• Field of Search: 370229-230, 370/252, 370465-466, 370/474, 709/223, 709/230
• US Class Current: 370/392
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• 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 41/0806 for initial configuration or provisioning, e.g. plug-and-play
• CPC Class Codes: H04L 41/0893 Assignment of logical groups to network elements
• CPC Class Codes: H04L 41/0894 Policy-based network configuration management
• CPC Class Codes: H04L 43/0817 by checking functioning
• CPC Class Codes: H04L 45/30 Routing of multiclass traffic
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/2416 Real-time traffic
• CPC Class Codes: H04L 47/2433 Allocation of priorities to traffic types
• CPC Class Codes: H04L 47/2475 for supporting traffic characterised by the type of applications
• CPC Class Codes: H04L 47/36 by determining packet size, e.g. maximum transfer unit [MTU]
• CPC Class Codes: H04L 63/0236 Filtering by address, protocol, port number or service, e.g. IP-address or URL
• CPC Class Codes: H04L 63/0272 Virtual private networks
• CPC Class Codes: H04L 63/029 Firewall traversal, e.g. tunnelling or, creating pinholes
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/061 for key exchange, e.g. in peer-to-peer networks cryptographic mechanisms or cryptographic arrangements for key agreement H04L9/0838
• CPC Class Codes: H04L 63/062 for key distribution, e.g. centrally by trusted party cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819
• CPC Class Codes: H04L 63/126 the source of the received data
• CPC Class Codes: H04L 63/164 : at the network layer
• CPC Class Codes: H04L 63/166 : at the transport layer
• CPC Class Codes: H04L 67/14 : Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04L 67/141 : Setup of application sessions admission control or resource allocation in data switching networks H04L47/70

Abstract

The present invention is generally directed towards a remote access architecture for providing peer-to-peer communications and remote access connectivity. In one embodiment, the remote access architecture of the present provides a method for establishing a direct connection between peer computing devices via a third computing device, such as a gateway. Additionally, the present invention provides the following techniques to optimize peer-to peer communications: 1) false acknowledgement of receipt of network packets allowing communications via a lossless protocol of packets constructed for transmission via a lossy protocol, 2) payload shifting of network packets allowing communications via a lossless protocol of packets constructed for transmission via a lossy protocol, 3) reduction of packet fragmentation by adjusting the maximum transmission unit (MTU) parameter, accounting for overhead due to encryption, 4) application-aware prioritization of client-side network communications, and 5) network disruption shielding for reliable and persistent network connectivity and access.

Claims

1. A method for transmitting unreliable transport protocol packets over a reliable transport layer protocol by shifting payload, the method comprising:

(a) intercepting, by an agent executing on a client, a first packet of an unreliable transport layer protocol transmitted by an application, the agent establishing a reliable transport layer protocol connection with a gateway;

(b) creating, by the agent, a first reliable transport layer protocol packet comprising a first reliable transport layer protocol header and the first packet as payload;

(c) transmitting, by the agent, the first reliable transport layer protocol packet to the gateway via the reliable transport layer protocol connection;

(d) intercepting, by the agent, a second packet of the unreliable transport layer protocol transmitted by the application;

(e) creating, by the agent, a second reliable transport layer protocol packet comprising the first reliable transport layer protocol header of the first reliable transport layer protocol packet as a header and the second packet as payload;

(f) transmitting, by the agent, the second reliable transport layer protocol packet to the gateway prior to receiving an acknowledgement of receipt for the first reliable transport layer protocol packet; and

(g) providing, by the agent to a network stack of the client, a false acknowledgement of receipt by the gateway of the first reliable transport layer protocol packet to prevent the network stack from executing a reliability mechanism.

2. The method of claim 1, wherein step (b) further comprises:

determining, by the agent, that the first packet is in the unreliable transport layer protocol; and

creating, responsive to the determination, the first reliable transport layer protocol packet.

3. The method of claim 1, wherein step (b) further comprises creating, by the agent, the first reliable transport layer protocol header with a predetermined port set to indicate that the first reliable transport layer protocol packet comprises a packet of the unreliable transport layer protocol.

4. The method of claim 1, wherein step (b) further comprises creating, by the agent, the first reliable transport layer protocol header with a header flag set to indicate that the first reliable transport layer protocol packet comprises a packet of the unreliable transport layer protocol.

5. The method of claim 1, wherein step (b) further comprises creating, by the agent, the first reliable transport layer protocol header with header information from the established reliable transport layer protocol connection with the gateway.

6. The method of claim 1, further comprising encrypting the first packet of the unreliable transport layer protocol or the second packet of the unreliable transport layer protocol.

7. The method of claim 1, further comprising encrypting the second packet of the unreliable transport layer protocol.

8. The method of claim 1, wherein step (f) is performed responsive to providing the false acknowledgement of receipt to the network stack of the client.

9. The method of claim 1, wherein executing a reliability mechanism comprises executing at least one of packet ordering, packet retransmission, flow control, sliding window algorithm, and nagle'"'"'s algorithm.

10. The method of claim 1, further comprising receiving an acknowledgement of receipt of the second reliable transport layer protocol packet from the gateway, the acknowledgement comprising updated header information from the established reliable transport layer protocol connection with the gateway.

11. The method of claim 10, further comprising creating, by the agent, a third reliable transport layer protocol packet comprising the updated header information as a header and the second packet of the unreliable transport layer protocol as payload, and transmitting the third reliable transport layer protocol packet to the gateway.

12. A method for transmitting user datagram protocol (UDP) packets over a transport control protocol (TCP) connection by shifting payload, the method comprising:

(a) intercepting, by an agent executing on a client, a first user datagram protocol packet (UDP) transmitted by an application, the agent establishing a transport control protocol (TCP) connection with a gateway;

(b) creating, by the agent, a first TCP packet comprising a first TCP header and the first UDP packet as payload;

(c) transmitting, by the agent, the first TCP packet to the gateway via the TCP connection;

(d) intercepting, by the agent, a second UDP packet transmitted by the application;

(e) creating, by the agent, a second TCP packet comprising the first TCP header as a header and the second UDP packet as payload;

(f) transmitting, by the agent, the second TCP packet to the gateway prior to receiving an acknowledgement of receipt for the first TCP packet; and

(g) providing, by the agent to a network stack of the client, a false acknowledgement of receipt by the gateway of the first TCP packet to prevent the network stack from executing a reliability mechanism.

13. The method of claim 12, wherein step (b) further comprises:

determining, by the agent, that the first packet is the UDP packet; and

creating, responsive to the determination, the first TCP packet.

14. The method of claim 12, wherein step (b) further comprises creating, by the agent, the first TCP header with a predetermined port set to indicate that the first TCP packet comprises the UDP packet.

15. The method of claim 12, wherein step (b) further comprises creating, by the agent, the first TCP header with a header flag set to indicate that the first TCP packet comprises the UDP packet.

16. The method of claim 12, wherein step (b) further comprises creating, by the agent, the first TCP header with header information from the established TCP connection with the gateway.

17. The method of claim 12, further comprising encrypting the first UDP packet.

18. The method of claim 12, further comprising encrypting the second UDP packet.

19. The method of claim 12, wherein step (f) is performed responsive to providing the false acknowledgement of receipt to the network stack of the client.

20. The method of claim 12, wherein executing a reliability mechanism comprises executing at least one of packet ordering, packet retransmission, flow control, sliding window algorithm, and nagle'"'"'s algorithm.

21. The method of claim 12, further comprising receiving an acknowledgement of receipt of the second TCP packet from the gateway, the acknowledgement comprising updated header information from the established TCP connection with the gateway.

22. The method of claim 21, further comprising creating, by the agent, a third TCP packet comprising the updated header information as a header and the second UDP packet as payload, and transmitting the third TCP packet to the gateway.