Packet aggregation

• US 7,839,876 B1
• Filed: 06/15/2006
• Issued: 11/23/2010
• Est. Priority Date: 01/25/2006
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Marvell International Limited (Marvell Technology Group Limited)
• Inventors: Shastry, Prabhashanker, Goel, Sandesh
• Primary Examiner(s): Rao; Seema S
• Assistant Examiner(s): MURPHY, RHONDA L
• Application Number:
  US11/454,102
• Time in Patent Office: 1,622 Days
• Field of Search: None
• US Class Current: 370/412
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/29 using a combination of thresholds
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04L 47/32 by discarding or delaying data units, e.g. packets or frames
• CPC Class Codes: H04L 47/58 Changing or combining different scheduling modes, e.g. multimode scheduling
• CPC Class Codes: H04W 28/065 using assembly or disassembly of packets

Abstract

A method comprises receiving packets; transferring the packets to an output circuit when aggregation of the packets is not enabled; transferring the packets to a queue when aggregation is enabled; enabling aggregation when a rate of receiving the packets into the queue is greater than a predetermined rate or a number of the packets in the output circuit>a first number; and generating aggregate packets each comprising packets in the queue, transferring each aggregate packet to the output circuit when a number of packets in the aggregate packet>a second number, and transferring the aggregate packet to the output circuit when a number of packets in the aggregate packet≦the second number, when a predetermined interval elapses, wherein the interval begins when the queue is empty when receiving a packet or a number of aggregate packets in a device receiving the aggregate packets<a third number.

Claims

1. An apparatus comprising:

an input circuit to receive packets of data;

an output circuit to receive the packets of data from the input circuit when aggregation of the packets of data is not enabled;

a queue to receive the packets of data from the input circuit when aggregation of the packets of data is enabled;

a control circuit to enable aggregation of the packets of data on occurrence of at least one of

a rate of receiving the packets of data by the input circuit is greater than a predetermined threshold rate, and

a number of the packets of data present in the output circuit is greater than a first predetermined threshold number; and

an aggregation circuit to generate aggregate packets each comprising a plurality of the packets of data received into the queue, to transfer each aggregate packet to the output circuit when a number of the packets of data in the aggregate packet is greater than a second predetermined threshold number, and to transfer the aggregate packet to the output circuit when a number of the packets of data in the aggregate packet is less than, or equal to, the second predetermined threshold number, on occurrence of at least one of

a predetermined interval elapses, wherein the predetermined interval begins when the queue is empty when receiving one of the packets of data, and

a number of the aggregate packets present in an input circuit of a further apparatus receiving the aggregate packets from the output circuit is less than a third predetermined threshold number.

2. The apparatus of claim 1:

wherein the control circuit modifies the second predetermined threshold number based on at least one of

durations of intervals between the packets of data received by the input circuit, and

a burst size of the packets of data received by the input circuit.

3. The apparatus of claim 1:

wherein the control circuit executes a timer to implement the predetermined interval.

4. A system comprising:

the apparatus of claim 1, and

the further apparatus, wherein the further apparatus comprises

a further control circuit to execute a timer to implement the predetermined interval, and to generate a timeout signal when the predetermined interval elapses, wherein the aggregation circuit receives the timeout signal.

5. The system of claim 4:

wherein the further control circuit modifies a duration of the predetermined interval based on at least one of the group consisting of

a rate of elapsing of the predetermined interval, and

durations of intervals between elapsing of the predetermined interval and receiving a subsequent one of the aggregate packets.

6. A system comprising:

the apparatus of claim 1, and

the further apparatus, wherein the further apparatus comprises

a media access control circuit (MAC) to receive the data, and

a physical-layer circuit (PHY) to transmit a signal representing the data.

7. The system of claim 6:

wherein the control circuit modifies the second predetermined threshold number based on at least one of

a transmit data rate of the PHY,

a maximum allowed duration of transmission of the aggregate packets, and

a packet error rate reported by the further apparatus.

8. A wireless network device comprising the system of claim 6, wherein the wireless network device is compliant with at least one standard selected from the group consisting of IEEE standards 802.11, 802.11a, 802.11b, 802.11g, 802.11n, 802.16, and 802.20.

9. A wireless network device comprising the system of claim 6, wherein the wireless network device is selected from the group consisting of:

a switch;

a router; and

a network interface controller.

10. The apparatus of claim 1:

wherein each of the packets of data comprises a respective Media Access Control (MAC) Service Data Units (MSDUs); and

wherein each of the aggregate packets comprises a respective Aggregate MSDU (A-MSDU).

11. An apparatus comprising:

input means for receiving packets of data;

output means for receiving the packets of data from the input means when aggregation of the packets of data is not enabled;

queue means for receiving the packets of data from the input means when aggregation of the packets of data is enabled;

control means for enabling aggregation of the packets of data on occurrence of at least one of

a rate of receiving the packets of data by the input means is greater than a predetermined threshold rate, and

a number of the packets of data present in the output means is greater than a first predetermined threshold number; and

aggregation means for generating aggregate packets each comprising a plurality of the packets of data received into the queue means, transferring each aggregate packet to the output means when a number of the packets of data in the aggregate packet is greater than a second predetermined threshold number, and transferring the aggregate packet to the output means when a number of the packets of data in the aggregate packet is less than, or equal to, the second predetermined threshold number, on occurrence of at least one of

a predetermined interval elapses, wherein the predetermined interval begins when the queue means is empty when receiving one of the packets of data, and

a number of the aggregate packets present in an input circuit of a further apparatus receiving the aggregate packets from the output means is less than a third predetermined threshold number.

12. The apparatus of claim 11:

wherein the control means modifies the second predetermined threshold number based on at least one of

durations of intervals between the packets of data received by the input means, and

a burst size of the packets of data received by the input means.

13. The apparatus of claim 11:

wherein the control means executes a timer to implement the predetermined interval.

14. A system comprising:

the apparatus of claim 11, and

the further apparatus, wherein the further apparatus comprises

further control means for executing a timer to implement the predetermined interval, and generating a timeout signal when the predetermined interval elapses, wherein the aggregation means receives the timeout signal.

15. The system of claim 14:

wherein the further control means modifies a duration of the predetermined interval based on at least one of the group consisting of

a rate of elapsing of the predetermined interval, and

durations of intervals between elapsing of the predetermined interval and receiving a subsequent one of the aggregate packets.

16. A system comprising:

the apparatus of claim 11, and

the further apparatus, wherein the further apparatus comprises

a media access control (MAC) means for receiving the data, and

a physical-layer (PHY) means for transmitting a signal representing the data.

17. The system of claim 16:

wherein the control means modifies the second predetermined threshold number based on at least one of

a transmit data rate of the PHY means,

a maximum allowed duration of transmission of the aggregate packets, and

a packet error rate reported by the further apparatus.

18. A wireless network device comprising the system of claim 16, wherein the wireless network device is compliant with at least one standard selected from the group consisting of IEEE standards 802.11, 802.11a, 802.11b, 802.11g, 802.11n, 802.16, and 802.20.

19. A wireless network device comprising the system of claim 16, wherein the wireless network device is selected from the group consisting of:

a switch;

a router; and

a network interface controller.

20. The apparatus of claim 11:

wherein each of the packets of data comprises a respective Media Access Control (MAC) Service Data Units (MSDUs); and

wherein each of the aggregate packets comprises a respective Aggregate MSDU (A-MSDU).

21. A method comprising:

receiving packets of data;

transferring the packets of data to an output circuit when aggregation of the packets of data is not enabled;

transferring the packets of data to a queue when aggregation of the packets of data is enabled;

enabling aggregation of the packets of data on occurrence of at least one of

a rate of receiving the packets of data is greater than a predetermined threshold rate, and

a number of the packets of data present in the output circuit is greater than a first predetermined threshold number; and

generating aggregate packets each comprising a plurality of the packets of data received into the queue, transferring each aggregate packet to the output circuit when a number of the packets of data in the aggregate packet is greater than a second predetermined threshold number, and transferring the aggregate packet to the output circuit when a number of the packets of data in the aggregate packet is less than, or equal to, the second predetermined threshold number, on occurrence of at least one of

a predetermined interval elapses, wherein the predetermined interval begins when the queue is empty when receiving one of the packets of data, and

a number of the aggregate packets present in a device receiving the aggregate packets from the output circuit is less than a third predetermined threshold number.

22. The method of claim 21, further comprising:

modifying the second predetermined threshold number based on at least one of

durations of intervals between the received packets of data, and

a burst size of the received packets of data.

23. The method of claim 21, further comprising:

timing the predetermined interval.

24. The method of claim 21:

wherein the device times the predetermined interval, and generates a timeout signal when the predetermined interval elapses.

25. The method of claim 24, further comprising:

modifying a duration of the predetermined interval based on at least one of the group consisting of

a rate of elapsing of the predetermined interval, and

durations of intervals between elapsing of the predetermined interval and receiving a subsequent one of the aggregate packets at the device.

26. The method of claim 21, further comprising:

transmitting a signal representing the data.

27. The method of claim 26, further comprising:

modifying the second predetermined threshold number based on at least one of

a transmit data rate of the signal representing the data,

a maximum allowed duration of transmission of the aggregate packets, and

a packet error rate reported by a receiver of the data.

28. The method according to claim 26 which is compliant with at least one standard selected from the group consisting of IEEE standards 802.11, 802.11a, 802.11b, 802.11g, 802.11n, 802.16, and 802.20.

29. The method of claim 21:

wherein each of the packets of data comprises a respective Media Access Control (MAC) Service Data Units (MSDUs); and

wherein each of the aggregate packets comprises a respective Aggregate MSDU (A-MSDU).

30. A computer program tangibly embodied in a machine-readable storage device for execution by a programmable processor, the computer program comprising instructions for:

causing received packets of data to be transferred to an output circuit when aggregation of the packets of data is not enabled;

causing the received packets of data to be transferred to a queue when aggregation of the packets of data is enabled;

enabling aggregation of the packets of data on occurrence of at least one of

a rate of receiving the packets of data is greater than a predetermined threshold rate, and

a number of the packets of data present in the output circuit is greater than a first predetermined threshold number; and

causing aggregate packets to be generated, each aggregate packet comprising a plurality of the packets of data received into the queue, causing each aggregate packet to be transferred to the output circuit when a number of the packets of data in the aggregate packet is greater than a second predetermined threshold number, and causing the aggregate packet to be transferred to the output circuit when a number of the packets of data in the aggregate packet is less than, or equal to, the second predetermined threshold number, on occurrence of at least one of

a predetermined interval elapses, wherein the predetermined interval begins when the queue is empty when receiving one of the packets of data, and

a number of the aggregate packets present in a device receiving the aggregate packets from the output circuit is less than a third predetermined threshold number.

31. The computer program of claim 30, further comprising instructions for:

modifying the second predetermined threshold number based on at least one of

durations of intervals between the received packets of data, and

a burst size of the received packets of data.

32. The computer program of claim 30, further comprising instructions for:

timing the predetermined interval.

33. The computer program of claim 30:

wherein the device times the predetermined interval, and generates a timeout signal when the predetermined interval elapses.

34. The computer program of claim 33, further comprising instructions for:

modifying a duration of the predetermined interval based on at least one of the group consisting of

a rate of elapsing of the predetermined interval, and

durations of intervals between elapsing of the predetermined interval and receiving a subsequent one of the aggregate packets at the device.

35. The computer program of claim 30, further comprising instructions for:

causing a signal representing the data to be transmitted.

36. The computer program of claim 35, further comprising instructions for:

modifying the second predetermined threshold number based on at least one of

a transmit data rate of the signal representing the data,

a maximum allowed duration of transmission of the aggregate packets, and

a packet error rate reported by a receiver of the data.

37. The computer program of claim 30:

wherein each of the packets of data comprises a respective Media Access Control (MAC) Service Data Units (MSDUs); and

wherein each of the aggregate packets comprises a respective Aggregate MSDU (A-MSDU).