Providing contention free quality of service to time constrained data

• US 20040246937A1
• Filed: 06/03/2003
• Published: 12/09/2004
• Est. Priority Date: 06/03/2003
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Abhishek, Abhishek, Ayyagari, Arun, Duong, Francis
• Granted Patent: US 7,349,422 B2
• Time in Patent Office: Days
• US Class Current: 370/345
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/65 Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04W 28/24 Negotiating SLA [Service Level Agreement]; Negotiating QoS [Quality of Service]
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/56 based on priority criteria
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02

Abstract

The principles of the present invention provide for providing contention free quality of service to wireless stations. A station indicates to an access point that higher priority data (e.g., time constrained data) is to be sent to the access point. The access point receives the indication and selects a slot time for the station based on the number of other stations that have also indicated higher priority data. A slot time is selected such that the station can check for access to a common wireless link before any stations with lower priority data (e.g., data without time constraints). The access point sends the selected slot time to the station and the station receives the slot time. When the station receives an indication that an application has higher priority data to send, the station checks the common wireless link for availability at the selected slot time.

Claims

1. In a station computer system that is network connectable, along with one or more other station computer systems, to an access point computer system over a common wireless link, the station computer system and the one or more other station computer systems being configured to exchange data packets with the access point computer system over the common wireless link, the data packets potentially including higher priority data having a higher priority than other lower priority data of a lower priority, a method for providing higher priority data contention free access to the common wireless link, the method comprising:

an act of indicating to the access point computer system that the station computer system can potentially send higher priority data over the common wireless link to the access point computer system;

an act of receiving a slot time from the access point, the slot time being a multiple of a time interval that was calculated based at least in part on the number of data classification enabled stations supported by the access point computer system, the slot time representing a fixed time when the station computer system can check for access to the common wireless link such that the station computer system does not have to contend with lower priority data;

an act of receiving an indication from an application that higher priority data is to be sent to the access point computer system; and

an act of checking the common wireless link at the slot time to determine if the common wireless link is available.

2. The method as recited in claim 1, wherein the act of receiving a slot time from the access point comprises an act of receiving a data packet from the station computer system that includes the slot time.

3. The method as recited in claim 2, wherein the act of receiving a data packet from the station computer system that includes the slot time comprises an act of receiving a beacon packet.

4. The method as recited in claim 1, wherein the act of receiving a slot time from the access point comprises an act of receiving a slot time that was selected based at least in part on the time interval between the end of a Short Inter Frame Space and the beginning of a contention window utilized by lower priority data.

5. The method as recited in claim 1, wherein the act of receiving a slot time from the access point comprises an act of receiving a slot time that will cause the station to wait the sum of a Short Inter Frame Space plus a multiple of the time interval for access to the common wireless link.

6. The method as recited in claim 1, wherein the act of receiving an indication from an application that higher priority data is to be sent to the access point computer system comprises an act of detecting that the packet type associated with the data corresponds to higher priority data.

7. The method as recited in claim 1, wherein the act of receiving an indication from an application that higher priority data is to be sent to the access point computer system comprises an act of receiving an indication that data has more restrictive time constraints.

8. The method as recited in claim 7, wherein the act of receiving an indication that data has more restrictive time constraints comprises an act of receiving an indication of voice over IP data.

9. The method as recited in claim 7, wherein the act of receiving an indication that data has more restrictive time constraints comprises an act of receiving an indication of streaming audio/video data.

10. The method as recited in claim 1, wherein the act of receiving an indication from an application that higher priority data is to be sent to the access point computer system comprises an act of receiving an indication from a data classification module.

11. The method as recited in claim 1, wherein the act of receiving an indication from an application that higher priority data is to be sent to the access point computer system comprises an act of transferring the higher priority data to a higher priority queue.

12. The method as recited in claim 1, wherein an act of checking the common wireless link at the slot time to determine if the common wireless link is available comprises an act of detecting that the common wireless link is available.

13. The method as recited in claim 12, further comprising:

an act of initiating transmission of the higher priority data to the access point computer system in response to detecting that the common wireless link is available.

14. The method as recited in claim 1, wherein an act of checking the common wireless link at the slot time to determine if the common wireless link is not available comprises an act of detecting that the common wireless link is busy.

15. The method as recited in claim 14, further comprising:

an act of deferring transmission of the higher priority data to the access point computer system in response to detecting that the common wireless link is not available.

16. In a station computer system that is network connectable, along with one or more other station computer systems, to an access point computer system over a common wireless link, the station computer system and the one or more other station computer systems being configured to exchange data packets with the access point computer system over the common wireless link, the data packets potentially including higher priority data having a higher priority than other lower priority data of a lower priority, a method for providing higher priority data contention free access to the common wireless link, the method comprising:

a step for being allocated a time when the station does not have to contend with lower priority data for access to the common wireless link such that higher priority data has an increased chance of accessing the common wireless before lower priority data;

an act of receiving an indication from an application that higher priority data is to be sent to the access point computer system; and

an act of checking the common wireless link at a slot time to determine if the common wireless link is available.

17. In an access point computer system that is network connectable to a plurality of station computer systems over a common wireless link, the access point computer system being configured to exchange data packets with each of the plurality of station computer systems over the common wireless link, the data packets potentially including higher priority data having a higher priority than other lower priority data of a lower priority, a method for providing higher priority data contention free access to the common wireless link, the method comprising:

an act of receiving an indication that a station computer system can potentially send higher priority data over the common wireless link to the access point computer system;

an act of selecting a slot time for the station computer system based on the number of other data classification enabled stations currently being supported by the access point computer system, the slot time being a multiple of the time interval and representing a fixed time when the station computer system can check for access to the common wireless link without having to contend with lower priority data from other station computer systems; and

an act of sending the selected slot time to the station computer system.

18. The method as recited in claim 17, further comprising:

an act of calculating the time interval based at least in part on the number of data classification enabled stations that can be supported by the access point computer system.

19. The method as recited in claim 17, further comprising:

an act of calculating the time interval based at least in part on the time interval between the end of a Short Inter Frame Space and the beginning of a contention window utilized by lower priority data.

20. The method as recited in claim 17, wherein the an act of selecting a slot time for the station computer system comprises an act of selecting a slot time based on the number of other stations that have already been assigned slot times.

21. The method as recited in claim 17, wherein the act of selecting a slot time for the station computer system comprises act of selecting a slot time that will cause the station computer system to wait the sum of a Short Inter Frame Space plus a multiple of the time interval before checking for access to the common wireless link.

22. The method as recited in claim 17, wherein the act of sending the selected slot time to the station computer system comprises an act of sending a data packet that includes the slot time.

23. The method as recited in claim 22, wherein the act of sending a data packet that includes the slot time comprises an act of sending a beacon packet.

24. In an access point computer system that is network connectable to a plurality of station computer systems over a common wireless link, the access point computer system being configured to exchange data packets with each of the plurality of station computer systems over the common wireless link, the data packets potentially including higher priority data having a higher priority than other lower priority data of a lower priority, a method for providing higher priority data contention free access to the common wireless link, the method comprising:

an act of receiving an indication that a station computer system can potentially send higher priority data over the common wireless link to the access point computer system; and

a step for allocating a time when the station will not have to contend with lower priority data such that higher priority data has an increased chance of accessing the common wireless before lower priority data.

25. A computer program product for use in a station computer system that is network connectable, along with one or more other station computer systems, to an access point computer system over a common wireless link, the station computer system and the one or more other station computer systems being configured to exchange data packets with the access point computer system over the common wireless link, the data packets potentially including higher priority data having a higher priority than other lower priority data of a lower priority, the computer program product for implementing a method for providing higher priority data contention free access to the common wireless link, the computer program product comprising one or more computer-readable media having stored thereon computer executable instructions that, when executed by a processor, cause the station computer system to perform the following:

indicate to the access point computer system that the station computer system can potentially send higher priority data over the common wireless link to the access point computer system;

receive a slot time from the access point, the slot time being a multiple of a time interval that was calculated based at least in part on the number of data classification enabled stations supported by the access point computer system, the slot time representing a fixed time when the station computer system can check for access to the common wireless link such that the station computer system does not have to contend with lower priority data;

receive an indication from an application that higher priority data is to be sent to the access point computer system; and

check the common wireless link at the slot time to determine if the common wireless link is available.

27. The computer program product as recited in claim 25, wherein the one or more computer-readable media include system memory.

26. The computer program product as recited in claim 26, wherein the one or more computer-readable media are physical media.

28. A computer program product for use in an access point computer system that is network connectable to a plurality of station computer systems over a common wireless link, the access point computer system being configured to exchange data packets with each of the plurality of station computer systems over the common wireless link, the data packets potentially including higher priority data having a higher priority than other lower priority data of a lower priority, the computer program product for implementing a method for providing higher priority data contention free access to the common wireless link, the computer program product comprising one or more computer-readable media having stored thereon computer executable instructions that, when executed by a processor, cause the access point computer system to perform the following:

receive an indication that a station point computer system can potentially send higher priority data over the common wireless link to the access point computer system;

select a slot time for the station computer system based on the number of other data classification enabled stations currently being supported by the access point computer system, the slot time being a multiple of the time interval and representing a fixed time when the station computer system can check for access to the common wireless link without having to contend with lower priority data from other station computer systems; and

send the selected slot time to the station computer system.

29. The computer program product as recited in claim 28, further comprising computer-executable instructions that, when executed by a processor, cause the access point computer system to perform the following:

calculate the time interval based on the number of data classification enabled stations that can be supported by the access point computer system and the time interval between the end of a Short Inter Frame Space and the beginning of a contention window utilized by lower priority data.

30. The computer program product as recited in claim 28, wherein the one or more computer-readable media are physical media.

31. The computer program product as recited in claim 28, wherein the one or more computer-readable media include system memory.