Systems and methods for additional retransmissions of dropped packets

• US 9,071,543 B2
• Filed: 04/03/2013
• Issued: 06/30/2015
• Est. Priority Date: 07/29/2003
• Status: Active Grant

• Current Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Original Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Inventors: Plamondon, Robert, Ovsiannikov, Michael, Samuels, Allen
• Primary Examiner(s): Ton, Dang
• Assistant Examiner(s): KAVLESKI, RYAN C
• Application Number:
  US13/856,263
• Publication Number:
  US 20130286835A1
• Time in Patent Office: 818 Days
• Field of Search: 370/242, 370/394, 714/1, 714/748
• US Class Current: 1/1
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/189 Transmission or retransmission of more than one copy of a message
• CPC Class Codes: H04L 2001/0092 Error control systems characterised by the topology of the transmission link
• CPC Class Codes: H04L 41/00 Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies
• CPC Class Codes: H04L 47/2466 using signalling traffic
• CPC Class Codes: H04L 67/2876 Pairs of inter-processing entities at each side of the network, e.g. split proxies
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/166 IP fragmentation; TCP segmentation

Abstract

Systems and methods for utilizing transaction boundary detection methods in queuing and retransmission decisions relating to network traffic are described. By detecting transaction boundaries and sizes, a client, server, or intermediary device may prioritize based on transaction sizes in queuing decisions, giving precedence to smaller transactions which may represent interactive and/or latency-sensitive traffic. Further, after detecting a transaction boundary, a device may retransmit one or more additional packets prompting acknowledgements, in order to ensure timely notification if the last packet of the transaction has been dropped. Systems and methods for potentially improving network latency, including retransmitting a dropped packet twice or more in order to avoid incurring additional delays due to a retransmitted packet being lost are also described.

Claims

1. A method for reducing retransmission costs, the method comprising:

determining, by a device, a packet loss rate associated with a connection between the device and a receiver;

identifying, by the device, a number of retransmissions of a transmission of a packet corresponding to the packet loss rate and a packet loss rate threshold from a plurality of retransmission numbers associated with a corresponding plurality of packet loss rate thresholds;

transmitting, by the device, a network packet to the receiver; and

retransmitting the network packet, by the device, a number of times equal to the identified number of retransmissions.

2. The method of claim 1, wherein retransmitting the network packet further comprises receiving an identification that the transmitted network packet was not received by the receiver, and retransmitting the network packet the number of retransmissions.

3. The method of claim 1, wherein retransmitting the network packet comprises retransmitting the network packet the number of retransmissions of times prior to expiration of a timeout of the first retransmission of the network packet.

4. The method of claim 1, further comprising determining the packet loss rate over a predetermined time period.

5. The method of claim 1, further comprising determining the packet loss rate as an average over a predetermined time period.

6. The method of claim 1, wherein identifying the number of retransmissions further comprises identifying a number of retransmissions inversely proportional to a determined transaction size.

7. The method of claim 1, wherein identifying the number of retransmissions further comprises identifying a number of retransmissions proportional to a priority assigned to the connection.

8. The method of claim 1, wherein identifying the number of retransmissions further comprises identifying a number of retransmissions inversely proportional to a latency tolerance of an application utilizing the connection.

9. The method of claim 1, wherein retransmitting the network packet comprises retransmitting the network packet the number of retransmissions, each retransmission temporally spaced such that two transmissions are unlikely to be affected by a single loss event.

10. A system for reducing retransmission costs, the system comprising:

a flow controller which;

determines a packet loss rate associated with a connection between the flow controller and a receiver, and

identifies a number of retransmissions of a transmission of a packet corresponding to the packet loss rate and a packet loss rate threshold from a plurality of retransmission numbers associated with a corresponding plurality of packet loss rate thresholds; and

a packet processor which;

transmits a network packet to the receiver, and

retransmits the network packet to the receiver a number of times equal to the identified retransmission number.

11. The system of claim 10, wherein the packet processor is further configured for receiving an identification that the transmitted network packet was not received by the receiver, and retransmitting the network packet the number of retransmissions.

12. The system of claim 10, wherein the packet processor is further configured for retransmitting the network packet the number of retransmissions of times prior to expiration of a timeout of the first retransmission of the network packet.

13. The system of claim 10, wherein the flow controller is further configured for determining the packet loss rate over a predetermined time period.

14. The system of claim 10, wherein the flow controller is further configured for determining the packet loss rate as an average over a predetermined time period.

15. The system of claim 10, wherein the flow controller is further configured for identifying a number of retransmissions inversely proportional to a determined transaction size.

16. The system of claim 10, wherein the flow controller is further configured for identifying a number of retransmissions proportional to a priority assigned to the connection.

17. The system of claim 10, wherein the flow controller is further configured for identifying a number of retransmissions inversely proportional to a latency tolerance of an application utilizing the connection.

18. The system of claim 10, wherein the packet processor is further configured for retransmitting the network packet the number of retransmissions, each retransmission temporally spaced such that two transmissions are unlikely to be affected by a single loss event.