Method and apparatus for determining and managing congestion in a wireless communications system

• US 8,953,573 B2
• Filed: 08/18/2011
• Issued: 02/10/2015
• Est. Priority Date: 07/23/2003
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Kwak, Joseph A., Rudolf, Marian, Hunkeler, Teresa Joanne, Rahman, Shamim Akbar, Cuffaro, Angelo A., Cave, Christopher R., Roy, Vincent, Touag, Athmane, LaSita, Frank, Ali, Ahmed, Marinier, Paul
• Primary Examiner(s): TORRES, MARCOS L
• Application Number:
  US13/212,632
• Publication Number:
  US 20110305139A1
• Time in Patent Office: 1,272 Days
• Field of Search: 370/338, 370/395.21, 370/395.43, 709/225, 455/452.1, 455/452.2, 455/453, 455/414.3
• US Class Current: 370/338
• CPC Class Codes: H04W 28/0205 at the air interface dynamic wireless traffic scheduling H04W72/12
• CPC Class Codes: H04W 28/0284 detecting congestion or overload during communication monitoring arrangements H04L43/00
• CPC Class Codes: H04W 28/14 using intermediate storage
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 72/00 Local resource management
• CPC Class Codes: H04W 72/27 between access points
• CPC Class Codes: H04W 74/08 Non-scheduled access, e.g. ALOHA hybrid access H04W74/02

Abstract

A method and apparatus may be used for network management via MAC measurements. The measurements may include WTRU uplink traffic loading measurement, and an AP service loading measurement. The measurements may be applicable to at least to layers 1 and 2 as applied to, for example, 802.11k in the context of OFDM and CDMA 2000 systems, but may be applicable to other scenarios as well. A method for determining and transmitting congestion information may be provided for a Wireless Local Area Network (WLAN) system. The method and apparatus may be used for managing congestion when congestion is detected. The method and apparatus may be used in wireless systems that use a Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) mechanism. The methods may be implemented in wireless transmit/receive units (WTRU)s and access points (AP)s of various forms.

Claims

1. A method for use in an access point (AP), the method comprising:

generating a message that includes a plurality of fields that correspond to a plurality of access categories including a voice category, a video category, a best effort category, and a background category, wherein an integer value is indicated in the message for each of the plurality of access categories; and

on a condition that a field of the plurality of fields is associated with a scaled representation of an average access delay, the integer value for the field of the plurality of fields indicates a first value, on a condition that a field of the plurality of fields represents that an access category of a respective one of the plurality of access categories is unavailable, the integer value for the field of the plurality of fields indicates a second value, and on a condition that a field of the plurality of fields represents that the scaled representation of the average access delay for an access category of the plurality of access categories is not available, the integer value for the field of the plurality of fields indicates a third value; and

transmitting the message to a wireless transmit/receive unit (WTRU).

2. The method of claim 1, wherein the average access delay is measured during a predetermined time period.

3. The method of claim 2, wherein the time period is thirty (30) seconds.

4. The method of claim 1, wherein the scaled representation is an 8 binary bit scaled representation.

5. The method of claim 4, wherein the 8 binary bit representation includes values from 1 to 252 that are a scaled representation of an average access delay for one of the plurality of access categories.

6. An access point (AP) comprising:

a processor configured to generate a message that includes a plurality of fields that correspond to a plurality of access categories including a voice category, a video category, a best effort category, and a background category, wherein an integer value is indicated in the message for each of the plurality of access categories; and

on a condition that a field of the plurality of fields is associated with a scaled representation of an average access delay, the integer value for the field of the plurality of fields indicates a first value, on a condition that a field of the plurality of fields represents that an access category of a respective one of the plurality of access categories is unavailable, the integer value for the field of the plurality of fields indicates a second value, and on a condition that a field of the plurality of fields represents that the scaled representation of the average access delay for an access category of the plurality of access categories is not available, the integer value for the field of the plurality of fields indicates a third value; and

a transmitter configured to transmit the message to a wireless transmit/receive unit (WTRU).

7. The AP of claim 6 further comprising:

a receiver configured to receive a service load indicator from another AP.

8. The AP of claim 6 wherein the average access delay is measured during a predetermined time period.

9. The AP of claim 8 wherein the time period is thirty (30) seconds.

10. The AP of claim 6 wherein the scaled representations are 8 binary bit scaled representation.

11. The AP of claim 10 wherein the 8 binary bit representation includes values from 1 to 252 that are a scaled representation of an average access delay for one of the plurality of access categories.

12. A method for use in a wireless transmit/receive unit (WTRU), the method comprising:

receiving a message that includes a plurality of fields that correspond to a plurality of access categories including a voice category, a video category, a best effort category, and a background category, wherein an integer value is indicated in the message for each of the plurality of access categories; and

on a condition that a field of the plurality of fields is associated with a scaled representation of an average access delay, the integer value for the field of the plurality of fields indicates a first value, on a condition that a field of the plurality of fields represents that an access category of a respective one of the plurality of access categories is unavailable, the integer value for the field of the plurality of fields indicates a second value, and on a condition that a field of the plurality of fields represents that the scaled representation of the average access delay for an access category of the plurality of access categories is not available, the integer value for the field of the plurality of fields indicates a third value; and

selecting an access point (AP) based on the message.

13. The method of claim 12, wherein the message includes an 8 binary bit scaled representation including values from 1 to 252 that are a scaled representation of an average access delay for one of the plurality of access categories.

16. The method of claim 12, wherein the average access delay is measured by the AP during a predetermined time period.

17. The method of claim 12, wherein the scaled representation is an 8 binary bit scaled representation.

14. A wireless transmit/receive unit (WTRU) comprising:

a receiver configured to receive a that includes a plurality of fields that correspond to a plurality of access categories including a voice category, a video category, a best category, and a background category, wherein an integer value is indicated in the message for each of the plurality of access categories; and

on a condition that a field of the plurality of fields is associated with a scaled representation of an average access delay, the integer value for the field of the plurality of fields indicates a first value, on a condition that a field of the plurality of fields represents that an access category of a respective one of the plurality of access categories is unavailable, the integer value for the field of the plurality of fields indicates a second value, and on a condition that a field of the plurality of fields represents that the scaled representation of the average access delay for an access category of the plurality of access categories is not available, the integer value for the field of the plurality of fields indicates a third value; and

a processor configured to select an access point (AP) based on the message.

15. The WTRU of claim 14 wherein the message includes an 8 binary bit scaled representation including values from 1 to 252 that is a scaled representation of an average access delay for one of the plurality of access categories.

18. The WTRU of claim 14, wherein the average access delay is measured by the AP during a predetermined time period.

19. The WTRU of claim 14, wherein the scaled representation is an 8 binary bit scaled representation.

20. A wireless transmit/receive unit (WTRU) comprising:

a receiver configured to receive, from an access point (AP), a message that includes a plurality of fields that correspond to a plurality of access categories including a voice category, a video category, a best effort category, and a background category, wherein an integer value is indicated in the message for each of the plurality of access categories; and

on a condition that a field of the plurality of fields is associated with a scaled representation of an average access delay, the integer value for the field of the plurality of fields indicates a first value, on a condition that a field of the plurality of fields represents that an access category of a respective one of the plurality of access categories is unavailable, the integer value for the field of the plurality of fields indicates a second value, and on a condition that a field of the plurality of fields represents that the scaled representation of the average access delay for an access category of the plurality of access categories is not available, the integer value for the field of the plurality of fields indicates a third value; and

a processor configured to decode the message.

21. The WTRU of claim 20, wherein the scaled representation of an average access delay includes a value from 1 to 252.

22. The WTRU of claim 20, wherein the average access delay is measured by the AP during a predetermined time period.

23. The WTRU of claim 20, wherein the scaled representation of an average access delay is an 8 binary bit scaled representation.

24. A method for use in a wireless transmit/receive unit (WTRU) comprising:

receiving, from an access point (AP), a message that includes a plurality of fields that correspond to a plurality of access categories including a voice category, a video category, a best effort category, and a background category, wherein an integer value is indicated in the message for each of the plurality of access categories; and

on a condition that a field of the plurality of fields is associated with a scaled representation of an average access delay, the integer value for the field of the plurality of fields indicates a first value, on a condition that a field of the plurality of fields represents that an access category of a respective one of the plurality of access categories is unavailable, the integer value for the field of the plurality of fields indicates a second value, and on a condition that a field of the plurality of fields represents that the scaled representation of the average access delay for an access category of the plurality of access categories is not available, the integer value for the field of the plurality of fields indicates a third value; and

decoding the message.

25. The method of claim 24, wherein the scaled representation of an average access delay includes a value from 1 to 252.

26. The method of claim 24, wherein the average access delay is measured by the AP during a predetermined time period.

27. The method of claim 24, wherein the scaled representation of an average access delay is an 8 binary bit scaled representation.