Systems and methods of QoS for and single stream ICA

• US 10,164,895 B2
• Filed: 01/11/2016
• Issued: 12/25/2018
• Est. Priority Date: 03/11/2011
• Status: Active Grant

• Current Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Original Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Inventors: Ovsiannikov, Michael
• Primary Examiner(s): Sheikh, Ayaz R
• Assistant Examiner(s): Carpio, Mariela Vidal
• Application Number:
  US14/992,751
• Publication Number:
  US 20160127251A1
• Time in Patent Office: 1,079 Days
• Field of Search: None
• CPC Class Codes: H04L 47/193 at the transport layer, e.g. TCP related
• CPC Class Codes: H04L 47/22 Traffic shaping
• CPC Class Codes: H04L 47/24 Traffic characterised by specific attributes, e.g. priority or QoS
• CPC Class Codes: H04L 47/2441 relying on flow classification, e.g. using integrated services [IntServ]
• CPC Class Codes: H04L 47/41 by acting on aggregated flows or links
• CPC Class Codes: H04L 47/6215 Individual queue per QOS, rate or priority
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

The present solution provides quality of service (QoS) for a stream of protocol data units via a single transport layer connection. A device receives via a single transport layer connection a plurality of packets carrying a plurality of protocol data units. Each protocol data unit identifies a priority. The device may include a filter for determining an average priority for a predetermined window of protocol data units and an engine for assigning the average priority as a connection priority of the single transport layer connection. The device transmits via the single transport layer connection the packets carrying those protocol data units within the predetermined window of protocol data units while the connection priority of the single transport layer connection is assigned the average priority for the predetermined window of protocol data units.

Claims

1. A method comprising:

identifying, by a device deployed as an intermediary between a client and a server, a rate of change of priority of packets received on a first connection between the client and the server;

selecting, by the device, a window size for determining an average priority of packets received within a window having the window size on the first connection, the window size selected based on the identified rate of change of priority, the window size comprising at least one of a data size or a period of time;

receiving within the selected window, by the device, a first packet identifying a first priority and a second packet identifying a second priority via the first connection, the first priority different than the second priority;

determining, by the device, a third priority for the first connection as an average of the first priority and the second priority of the packets received within the selected window; and

transmitting, by the device via the first connection, the first packet and the second packet received within the selected window at the third priority.

2. The method of claim 1, wherein the first connection comprises a transport layer connection between the client and the server traversing the device.

3. The method of claim 1, wherein determining the third priority for the connection further comprises identifying, by the device, priorities in a plurality of virtual streams or channels carried via the first packet and the second packet, at least one virtual stream or channel having a different priority than another virtual stream or channel.

4. The method of claim 1, further comprising determining, by the device, a fourth priority for the connection by computing a second average of priorities identified via a third packet and fourth packet received within a second predetermined window.

5. The method of claim 4, further comprising transmitting, by the device via the first connection, the third packet and the fourth packet within the second predetermined window based on the fourth priority.

6. The method of claim 1, wherein selecting the window size further comprises selecting a second window size for determining an average priority of packets received within the window on a second connection between the client and the server traversing the device, based on an identified rate of change or priority of packets received on the second connection, the second window size different from the window size selected for the first link.

7. The method of claim 1, wherein selecting the window size is further based on at least one of a number of bytes, a number of packets, a number of protocol data units, or changes in priority.

8. The method of claim 1, further comprising setting, by the device, a field in the first packet or the second packet to identify the third priority of the first connection.

9. The method of claim 1, wherein determining the third priority for the first connection further comprises determining, by a filter of the device, the average of priorities using one of finite impulse response (FIR) filtering or infinite impulse response (IIR) filtering.

10. The method of claim 1, further comprising controlling, by the device, the rate of change to the third priority of the first connection.

11. A system comprising:

a device, deployed as an intermediary between a client and a server, configured to identify a rate of change of priority of packets received on a first connection between the client and the server, and to receive a first packet identifying a first priority and a second packet identifying a second priority via the first connection within a predetermined window, the first priority different than the second priority, the predetermined window having a size, selected by the device, comprising at least one of a data size or a period of time for determining an average priority of packets received within the window, the window size selected based on the identified rate of change of priorities received via the first connection;

a filter of the device configured to determine a third priority for the first connection as an average of the first priority and the second priority of the packets received within the selected window; and

wherein the device is configured to transmit via the first connection the first packet and the second packet received within the selected window based on the third priority.

12. The system of claim 11, wherein the first connection comprises a transport layer connection between the client and the server traversing the device.

13. The system of claim 11, wherein the device is further configured to identify priorities in a plurality of virtual streams or channels carried via the first packet and the second packet, at least one virtual stream or channel having a different priority than another virtual stream or channel.

14. The system of claim 11, wherein the filter is further configured to determine a fourth priority for the first connection by computing a second average of priorities identified via a third packet and a fourth packet received within a second predetermined window.

15. The system of claim 14, wherein the device is further configured to transmit via the first connection, the third packet and the fourth packet based on the fourth priority.

16. The system of claim 11, wherein the device is further configured to assign the size of the predetermined window to the first connection based on one of link utilization or historical statistics of the connection.

17. The system of claim 11, wherein the size of the predetermined window is further based on at least one of a number of bytes, a number of packets, a number of protocol data units, or changes in priority.

18. The system of claim 11, wherein the device is further configured to set a field in the first packet or the second packet to identify the third priority of the connection.

19. The system of claim 11, wherein the filter is further configured to determine the average of priorities using one of finite impulse response (FIR) filtering or infinite impulse response (IIR) filtering.

20. The system of claim 11, wherein the device is further configured to control the rate of change to the third priority of the first connection.