Method and Apparatus for Packet Aggregation Transmission

• US 20110243055A1
• Filed: 03/29/2011
• Published: 10/06/2011
• Est. Priority Date: 03/31/2010
• Status: Abandoned Application

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Tian, Ji Feng, Li, Zhi Jun, Keller, Stefan, Lampe, Mattias
• Application Number:
  US13/074,775
• Publication Number:
  US 20110243055A1
• Time in Patent Office: Days
• US Class Current: 370/312
• CPC Class Codes: H04L 1/0007 by modifying the frame length
• 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 2001/0093 Point-to-multipoint

Abstract

A method and apparatus for packet aggregation transmission which are for application in a system comprising a transmitting end and at least two receiving ends, wherein the method comprises, for each receiving end, determining respectively a hold-up condition of subpackets at the transmitting and receiving ends at the current transmitting time, and determining the receiving end corresponding to the worst hold-up condition of the subpackets at the transmitting and receiving ends, and performing a packet aggregation transmission to the determined receiving end at the current transmitting time. The present invention is directed to point-to-multipoint data transmission, can solve the problem of transmission time sequence for a plurality of receiving ends, and improves the instantaneity of a system to the maximum degree possible.

Claims

1. A method for packet aggregation transmission in a system comprising a transmitting end and at least two receiving ends, the method comprising:

A. determining, in the system, for each of the receiving ends a respective hold-up condition of subpackets at the transmitting end and the each of the receiving end at a current transmitting time; and

B. determining, in the system, a determined receiving end as one of the at least two receiving ends corresponding to a worst hold-up condition of the subpackets at the transmitting end and the each of the receiving ends, and performing a packet aggregation transmission to the determined receiving end at the current transmitting time.

2. The method according to claim 1, wherein the hold-up condition of the subpackets at the transmitting and the each of the receiving ends is a sum N_i of a number of the subpackets held-up at the transmitting and the each of the receiving ends, wherein i is an identifier of the receiving end;

and wherein the determined receiver end is the receiving end corresponding to a maximum value of the sum N_i.

3. The method according to claim 2, wherein, when said system uses a mechanism of distributed coordination function (DCF) mechanism, the sum N_i meets the equation N_i=S_i^D1−

S_i^D2, where S_i^D1 is a largest serial number of the subpacket in a transmitting cache at the transmitting end corresponding to the receiving end with an identifier i at the current transmitting time, and S_i^D2 is a smallest serial number of the subpacket in a transmitting queue at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time; and

wherein, when said system uses a point coordination function (PCF) mechanism, the value of said N_i is N_i=a_i(S_i^D1−

S_i^D2)+b_i(S_i^U1+S_i^U2), where S_i^U1 is a largest serial number of the subpacket in a receiving cache at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time, S_i^U2 is a smallest serial number of the subpacket in the receiving cache at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time, a_i is a weight value of a transmission urgency of downstream data corresponding to the receiving end with the identifier i, and b_i is a weight value of a transmission urgency of upstream data corresponding to the receiving end with the identifier i.

4. The method according to claim 1, wherein the hold-up condition of the subpackets at the transmitting end and the each of the receiving ends is a sum T_i of the hold-up time period of the subpackets at said transmitting end and the each of the receiving ends, and wherein i is an identifier of the receiving end;

and the determined receiving end is the receiving end corresponding to a maximum value of T_i.

5. The method according to claim 4, wherein, when said system uses a mechanism of distributed coordination function (DCF) mechanism, T_i is T_i=T_i^D1−

T_i^D2, where T_i^D1 is a largest time stamp value of the subpacket in a transmitting cache at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time, and T_i^D2 is a smallest time stamp value of the subpacket in a transmitting queue at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time; and

wherein, when said system uses a mechanism of point coordination function (PCF) mechanism, a value of T_i is T_i=a_i(T_i^D1−

T_i^D2)+b_i(T_i^U1+T_i^U2), where T^iU1 is the largest time stamp value of the subpacket in the receiving cache at a transmitting end corresponding to the receiving end with the identifier i at the current transmitting time, T_i^U2 is a smallest time stamp value of the subpacket in the receiving cache at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time, a_i is a weight value of a transmission urgency of downstream data corresponding to the receiving end with the identifier i, and b_i is a weight value of the transmission urgency of upstream data corresponding to the receiving end with the identifier i.

6. The method according to claim 1, wherein after said step B, the method further comprises:

deleting by said transmitting end successfully transmitted subpackets from a transmitting queue at the transmitting end corresponding to the determined receiving end in accordance with a returned response from the determined receiving end regarding the packet aggregation transmission, and proceeding to step A at a next transmitting time.

7. An apparatus for packet aggregation transmission in a system comprising a transmitting end and at least two receiving ends, the apparatus being is set at the transmitting end, the apparatus comprising:

a hold-up condition determination unit configured to determine for each of the receiving ends respectively a hold-up condition of subpackets at the transmitting and the each of the receiving ends at a current transmitting time;

a receiving end determination unit configured to determine a determined as one of the at least two receiving ends corresponding to a worst hold-up condition of the subpackets at the transmitting and receiving ends; and

an aggregation transmission unit configured to perform a packet aggregation transmission to the determined receiving end determined by said receiving end determination unit at the current transmitting time.

8. The apparatus according to claim 7, wherein said hold-up condition of the subpackets at the transmitting end and the each of the receiving ends is a sum N_i of a number of subpackets held-up at the transmitting enc and the each of the receiving ends, where i is an identifier of the receiving end;

and

wherein the determined receiving end is the receiving end corresponding to the maximum value of N_i.

9. The apparatus according to claim 8, wherein, when said system uses a mechanism of distributed coordination function (DCF) mechanism, the hold-up condition determination unit comprises:

a first serial number determination sub-unit configured to determine S_i^D1 and S_i^D2 respectively for the each of the receiving ends, where S_i^D1 is a largest serial number of the subpacket in a transmitting cache at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time, and S_i^D2 is a smallest serial number of the subpacket in the transmitting queue at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time; and

a first hold-up number determination sub-unit configured to determine the number N_i of the subpackets held-up at the transmitting and the each of the receiving ends in accordance with N_i=S_i^D1−

S_i^D2; and

wherein, when the system uses a point coordination function (PCF) mechanism, the hold-up condition determination unit comprises;

a second serial number determination sub-unit for determining S_i^D1, S_i^D2, S_i^U1 and S_i^U2 respectively for the each of the receiving ends, where S_i^U1 is a largest serial number of the subpacket in a receiving cache at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time, and S_i^U2 is a smallest serial number of the subpacket in the receiving cache at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time; and

a second hold-up number determination sub-unit configured to determines a number N_i of the subpackets held-up at the transmitting and receiving ends in accordance with N_i=a_i(S_i^D1−

S_iD2)+b_i(S_i^U1−

S_i^U2) where a_i is a weight value of a transmission urgency of downstream data corresponding to the receiving end with the identifier i, and b_i is a weight value of the transmission urgency of upstream data corresponding to the receiving end with the identifier i.

10. The apparatus according to claim 7, wherein the hold-up condition of the subpackets at the transmitting end and the each of the receiving ends is a sum T_i of a hold-up time period of the subpackets at the transmitting end and the each of the receiving ends, where i is an identifier of the receiving end;

and

wherein the determined receiving end is the receiving end corresponding to the maximum value of T_i.

11. The apparatus according to claim 10, wherein, when the system uses a distributed coordination function (DCF) mechanism, the hold-up condition determination unit comprises:

a first time stamp determination sub-unit configured to determine T_i^D1 and T_i^D2 respectively for the each of the receiving ends, where T_i^D1 is a largest time stamp value of the subpacket in a transmitting cache at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time, and T_i^D2 is a smallest time stamp value of the subpacket in the transmitting queue at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time; and

a first hold-up time period determination sub-unit configured to determine the sum T_i of the hold-up time period of the subpackets at the transmitting end and the each of the receiving ends according to T_i=T_i^D1−

T_i^D2; and

wherein, when the system uses a point coordination function (PCF) mechanism, the hold-up condition determination unit comprises;

a second time stamp determination sub-unit configured to determine T_i^D1, T_i^D2, T_i^U1 and T_i^U2 respectively for the each of the receiving ends, where T^iU1 is a largest time stamp value of the subpacket in a receiving cache at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time, and T_i^U2 is a smallest time stamp value of the subpacket in the receiving cache at the transmitting end corresponding to the receiving end with the identifier i at the current transmitting time; and

a second hold-up time period determination sub-unit configured to determine the sum T_i of the hold-up time period of the subpackets at the transmitting end and the each of the receiving ends according to) T_i=a_i(T_i^D1−

T_i^D2)+b_i(T_i^U1+−

T_i^U2), where a_i is a weight value of the transmission urgency of downstream data corresponding to the receiving end with the identifier i, and b_i is a weight value of a transmission urgency of upstream data corresponding to the receiving end with the identifier i.

12. The apparatus according to claim 7, further comprising:

a transmission response processing unit configured to delete successfully transmitted subpackets from a transmitting queue at the transmitting end corresponding to said determined receiving end in accordance with a returned response from the determined receiving end regarding the packet aggregation transmission.

13. A method for packet aggregation transmission, comprising:

duplicating, by a transmitting end of a system, N copies of subpackets to be retransmitted in a transmitting queue after deleting successfully transmitted subpackets from the transmitting queue according to a returned response from a receiving end regarding a packet aggregation transmission; and

performing a packet aggregation transmission of the N subpackets together with the subpackets sent into the transmitting queue from a transmitting cache;

wherein, N is an integer greater than 1.

14. The method according to claim 13, wherein N is one of a preset value, a value related to retransmission times for said subpackets to be retransmitted and a value related to an instantaneity requirement at the receiving end.

15. The method according to claim 13, wherein, during the step of performing the packet aggregation transmission, N subpackets are one of placed at a position set in an aggregated packet and placed at a position calculated one of randomly and pseudo-randomly in the aggregated packet.

16. The method according to claim 14, wherein, during the step of performing the packet aggregation transmission, N subpackets are one of placed at a position set in an aggregated packet and placed at a position calculated one of randomly and pseudo-randomly in the aggregated packet.

17. An apparatus for packet aggregation transmission, said apparatus being set at a transmitting end, the apparatus comprising:

a response processing unit configured to delete successfully transmitted subpackets from the transmitting queue in accordance with a returned response from a receiving end regarding a packet aggregation transmission and to send a process notification to said packet duplication unit;

a packet duplication unit configured to duplicate N copies of subpackets to be retransmitted in a transmitting queue after having received said process notification; and

an aggregation transmission unit configured to perform the packet aggregation transmission of the duplicated N subpackets together with the subpackets sent into the transmitting queue from a transmitting cache;

wherein, N is an integer greater than 1.

18. The apparatus according to claim 17, wherein N is one of a preset value, a value related to the retransmission times for said subpackets to be retransmitted and a value related to the instantaneity requirement at said receiving end.

19. The apparatus according to claim 17, wherein, during said packet aggregation transmission, said aggregation transmission unit places N subpackets one of at a position set in an aggregated packet and at a position calculated one of randomly and pseudo-randomly in the aggregated packet.

20. The apparatus according to claim 18, wherein, during said packet aggregation transmission, said aggregation transmission unit places N subpackets one of at a position set in an aggregated packet and at a position calculated one of randomly and pseudo-randomly in the aggregated packet.