CN103079231A

Movatterモバイル変換

Info

Publication number: CN103079231A
Application number: CN201310043851XA
Authority: CN
Inventors: 张虎; 范成龙
Original assignee: Beijing Autelan Technology Co Ltd
Current assignee: Beijing Hua Xinaotian Network Technology Co ltd
Priority date: 2013-02-04
Filing date: 2013-02-04
Publication date: 2013-05-01

Abstract

The invention discloses a device and a method for multicast-to-unicast based on a wireless local area network in an AP (Access Point). The device comprises a power statistic module, a speed calculating module and a multicast-to-unicast module, wherein the power statistic module is used for making a statistics on power information of each terminal; the speed calculating module is used for calculating the optimal speed of each terminal according to the success rate of the unicast frame speed; the multicast-to-unicast operation module is used for classifying the terminals into high-speed terminals and low-speed terminals according to the optimal speed calculated by the speed calculating module and the multicasting speed; with regard to the low-speed terminals, a multicast mode is converted into a unicast mode; and multicast frames are copied according to the power information statistics made by the power statistic module, and the copied frames are respectively sent to each low-speed terminal in all the low-speed terminals in a unicast mode, wherein the multicast speed is a basic speed selected from any one basic speeds supported by the AP.

Description

In AP, turn the apparatus and method of clean culture based on the multicast of WLAN (wireless local area network)

Technical field

The present invention relates to the apparatus and method that a kind of multicast based on WLAN (wireless local area network) turns clean culture, more particularly, relate to a kind of apparatus and method that multicast mode are converted to mode of unicast by the transmission performance that compares multicast frame and unicast frame.

Background technology

Fig. 1 illustrates the multicast mechanism of WLAN (wireless local area network) of the prior art.With reference to Fig. 1, the multicast mechanism of WLAN (wireless local area network) of the prior art is: 1, the coded system (can guarantee the coded system that all terminals receive) by poor efficiency is sent to wireless network card with multicast packet; 2, AP is by higher transmitting power transmission group broadcasting frame,, receives the transmitting power transmission group broadcasting frame of this multicast frame can guarantee farthest terminal that is.

In the multicast mechanism of the WLAN (wireless local area network) of prior art, the coded system of frame is to use the minimum a kind of coded system of throughput.The transmitting power that AP uses is maximum, may have influence on other Basic Service Sets.In addition, the multicast mechanism of the WLAN (wireless local area network) of prior art can't guarantee whether the not good terminal of receiving ability can successfully receive, and causes TCP (transmission control protocol) layer retransmission rate higher.

It is to be the frame of a plurality of receiving terminals with destination address that multicast turns unicast technique, sends the process of single receiving terminal to by the method that copies.Multicast frame does not need to carry out ACK at link layer determines that unicast frame needs ACK to determine that the conversion that multicasts to clean culture can reduce data to a certain extent in the retransmission rate of TCP layer at link layer.

Multicast frame is being changed in the process of unicast frame, by according to AP (access point) radio-frequency information of terminal on every side, determine which terminal need to receive unicast frame and which terminal receiving group frame, thereby can promote to a certain extent the overall performance of Basic Service Set, minimizing is on the impact of other Basic Service Sets, wherein, described radio-frequency information comprises rate information and power information.

Summary of the invention

The invention discloses the apparatus and method that a kind of multicast based on WLAN (wireless local area network) turns clean culture, the method is converted to mode of unicast by the transmission performance according to multicast frame and unicast frame with multicast mode, can improve the entire throughput of Basic Service Set, reduce the retransmission rate that basic service is concentrated, and reduce the impact on other Basic Service Sets.

According to an aspect of the present invention, provide a kind of multicast based on WLAN (wireless local area network) in AP to turn the device of clean culture, having comprised: the power statistic module, add up the power information of each terminal; The rate calculations module according to the success rate of unicast frame speed, is calculated the iptimum speed that AP sends to each terminal; Multicast turns the unicast operation module, and iptimum speed and multicast speed according to the rate calculations module is calculated are categorized as two-forty terminal and low rate terminal with terminal; For the low rate terminal, multicast mode is converted into mode of unicast; Power information according to power statistic module statistics copies multicast frame, and the frame after copying is sent to respectively each low rate terminal in all low rate terminals by mode of unicast; Wherein, multicast speed is the basic rate of selecting in from the basic rate that AP supports any one.

According to a further aspect in the invention, provide a kind of multicast based on WLAN (wireless local area network) in AP to turn the method for clean culture, having comprised: the power information of adding up each terminal; According to the success rate of unicast frame speed, calculate the iptimum speed that AP sends to each terminal; Iptimum speed and multicast speed according to the rate calculations module is calculated are categorized as two-forty terminal and low rate terminal with terminal; For the low rate terminal, multicast mode is converted into mode of unicast; Power information according to power statistic module statistics copies multicast frame, and the frame after copying is sent to respectively each low rate terminal in all low rate terminals by mode of unicast; Wherein, multicast speed is the basic rate of selecting in from the basic rate that AP supports any one.

Description of drawings

By the description of carrying out below in conjunction with accompanying drawing, above and other purpose of the present invention and characteristics will become apparent, wherein:

Fig. 1 illustrates the schematic diagram of the multicast mechanism based on WLAN (wireless local area network) of the prior art.

Fig. 2 illustrates the schematic diagram based on the transfer of data of WLAN (wireless local area network) according to the embodiment of the invention.

Fig. 3 illustrates the block diagram that turns the clean culture device according to the multicast based on WLAN (wireless local area network) in AP of the embodiment of the invention.

Fig. 4 illustrates the flow chart based on the method for the calculating iptimum speed of WLAN (wireless local area network) according to the embodiment of the invention.

Fig. 5 illustrates the flow chart that turns the method for clean culture according to the multicast based on WLAN (wireless local area network) in AP of the embodiment of the invention.

Embodiment

Now, embodiments of the invention are described with reference to the accompanying drawings more fully.In the accompanying drawings, identical label represents identical element.

In Fig. 2, multicast turnsclean culture device 200 according to the iptimum speed that AP sends to each terminal, determines whether and multicast mode need to be converted to mode of unicast.As shown in Figure 2, for terminal S1, S2 and S3, because its iptimum speed is greater than multicast speed, therefore do not need the multicast frame that sends to terminal S1, S2 and S3 is changed (here, iptimum speed refers to the iptimum speed that AP sends to each terminal, multicast speed refers to the basic rate of selecting in from the basic rate that AP supports any one), that is to say, according to the transmitting power of terminal S1, S2 and S3 frame is directly sent to terminal S1, S2 and S3 with multicast mode.And for terminal S4 and S5, because its iptimum speed is less than multicast speed, therefore, multicast frame is copied, and the frame after will copying according to the transmitting power of terminal S4 and S5 sends to respectively terminal S4 and S5 in the mode of clean culture.That is to say, compared with prior art, according to the wireless driver module of the embodiment of the invention not needs carry out the operation that multicast mode is converted to mode of unicast, in addition, because other operation that this wireless driver module is carried out is identical with the operation that wireless driver module of the prior art is carried out, and therefore omits for simplicity detailed description.

Below, describe structure and the operation that multicast among the AP turnsclean culture device 200 in detail with reference to Fig. 3 and Fig. 4.

Fig. 3 illustrates the block diagram that the multicast based on WLAN (wireless local area network) shown in Fig. 2 turns clean culture device 200.Device 200 comprises thatpower statistic module 210,rate calculations module 220 and multicast turn unicast operation module 230.The power information of each terminals ofpower statistic module 210 statistics, described power information comprise that the optimum receiving signal intensity of each terminal and AP are to the best strength of transmitted signals of each terminal.Rate calculations module 220 uses the method for calculating iptimum speed to calculate the iptimum speed that AP sends to each terminal according to the success rate of unicast frame speed.Specifically,rate calculations module 220 is by traveling through each speed that sends to each terminal in described each terminal, if the speed in described each speed is less than or equal to the algorithm maximum rate and throughput corresponding to described speed is maximum throughput, then described speed is defined as iptimum speed.Multicast turns iptimum speed and the multicast speed thatunicast operation module 230 is calculated according to the rate calculations module, terminal is categorized as two-forty terminal and low rate terminal, specifically, when the iptimum speed of terminal during more than or equal to multicast speed, this terminal is categorized as the two-forty terminal, when the iptimum speed of terminal during less than multicast speed, this terminal is categorized as the low rate terminal; Afterwards, for the low rate terminal, multicast mode is converted into mode of unicast, and for the two-forty terminal, keeps multicast mode constant; Next, according to the power information of power statistic module, multicast frame is sent to all two-forty terminals, unicast frame is sent to respectively each low rate terminal in all low rate terminals.

Below, describe the operation of rate calculations module in detail with reference to Fig. 4.

In Fig. 4, index represents the index value that speed is corresponding, and rate_length represents the length of rate set.Alg_rate_index is illustrated in index corresponding to algorithm maximum rate in the method for calculating iptimum speed.RateMAX represents the speed of the maximum that AP supports.For example, for an array a={1,2,5.5,11,12,18,24,36,48,54......, 300} (this array is incremental data), its rate set is a[0], a[1], a[2], a[3], a[4] and, a[5] ..., a[N] (N is integer), rate_length is N+1; RateMAX is a[N]; Index represents the subscript of array, i.e. index corresponding to speed, the speed corresponding with index can be expressed as a[index]; Alg_rate_index is a value in [0, N], and its initial value can be arranged by the user, alg_rate_index meeting real-time update, the speed corresponding with alg_rate_index can be expressed as a[alg_rate_index].

Below, describe the step that the through-rate computing module calculates the iptimum speed algorithm in detail with reference to Fig. 4.

Instep 401, index is initialized as 0, alg_rate_index is initialized as N-m (m is the nonnegative integer less than N).

Instep 402, determine that whether index is greater than rate_length.If determine that index is less than or equal to rate_length, then process proceeding tostep 403; If determine index greater than rate_length, then process proceeding tostep 409.

Instep 403, determine a[index] whether greater than a[alg_rate_index].If a[index] be less than or equal to a[alg_rate_index], then process and proceed tostep 405; If a[index] greater than a[alg_rate_index], then process the value (that is, the value of index+1 being assigned to index) of upgrading index in step 404, return afterwardsstep 402.

Instep 405, determine a[index] throughput whether be maximum throughput.If determine a[index] throughput be maximum throughput, then process proceeding tostep 407, if determine a[index] throughput be not maximum throughput, then process the value of upgrading index instep 406, return afterwards step 402.For example, as a[index] throughput ratio a[0] throughput to a[index-1] throughput in maximum when large, a[index] throughput be maximum throughput, otherwise be not maximum throughput.Wherein, pass through equation: throughput=speed * success rate obtains throughput.

Instep 407, with a[index] be recorded as iptimum speed (being designated as good_rate at this).Afterwards, process the value of upgrading index in step 408, return afterwardsstep 402.

Instep 409, judge whether following condition is set up: good_rate is not equal to rateMAX and good_rate equals a[alg_rate_index] and good_rate success rate＞88%, if this condition is set up, then process proceeding tostep 410, if this condition is false, then processing finishes.

Instep 410, the value of alg_rate_index+1 is assigned to alg_rate_index, as the initial value of the alg_rate_index in the method for calculating iptimum speed next time, and good_rate is set to a[alg_rate_index].

With reference to Fig. 5, in step 501, add up the power information of each terminal, described power information comprises that the optimum receiving signal intensity of each terminal and AP are to the best strength of transmitted signals of each terminal.

In step 502, according to the success rate of unicast frame speed, use the method for calculating iptimum speed to calculate the iptimum speed that AP sends to each terminal.The method of calculating iptimum speed comprises: by each speed that sends to each terminal in described each terminal is traveled through, if the speed in described each speed is less than or equal to the algorithm maximum rate and throughput corresponding to described speed is maximum throughput, then described speed is defined as iptimum speed.

In step 503, according to iptimum speed and the multicast speed calculated in step 502, terminal is categorized as two-forty terminal and low rate terminal, specifically, when the iptimum speed of terminal during more than or equal to multicast speed, this terminal is categorized as the two-forty terminal, when the iptimum speed of terminal during less than multicast speed, this terminal is categorized as the low rate terminal; Afterwards, for the low rate terminal, multicast mode is converted into mode of unicast, and for the two-forty terminal, keeps multicast mode constant; Next, the power information according in step 501 statistics sends to all two-forty terminals with multicast frame, and unicast frame is sent to respectively each low rate terminal in all low rate terminals.

According to the present invention, by multicast mode being converted to the method for mode of unicast according to the transmission performance of multicast frame and unicast frame, can improve the entire throughput of Basic Service Set, reduce the retransmission rate that basic service is concentrated, and reduce the impact on other Basic Service Sets.

Although specifically shown with reference to embodiments of the invention and described the present invention, but it should be appreciated by those skilled in the art, in the situation that does not break away from the spirit and scope of the present invention that are defined by the claims, can carry out various changes on form and the details to it.

Claims

1. the multicast based on WLAN (wireless local area network) in AP turns the device of clean culture, comprising:

The power statistic module is added up the power information of each terminal;

The rate calculations module according to the success rate of unicast frame speed, is calculated the iptimum speed that AP sends to each terminal;

Multicast turns the unicast operation module, and iptimum speed and multicast speed according to the rate calculations module is calculated are categorized as two-forty terminal and low rate terminal with terminal; For the low rate terminal, multicast mode is converted into mode of unicast; Power information according to power statistic module statistics copies multicast frame, and the frame after copying is sent to respectively each low rate terminal in all low rate terminals by mode of unicast; Wherein, multicast speed is the basic rate of selecting in from the basic rate that AP supports any one.

2. device as claimed in claim 1 wherein, for the two-forty terminal, keeps multicast mode constant.

3. device as claimed in claim 1, wherein, described power information comprises that the optimum receiving signal intensity of each terminal and AP are to the best strength of transmitted signals of each terminal.

4. device as claimed in claim 1, wherein, when the iptimum speed of terminal during more than or equal to multicast speed, multicast turns the unicast operation module described terminal is categorized as the two-forty terminal; When the iptimum speed of terminal during less than multicast speed, multicast turns the unicast operation module described terminal is categorized as the low rate terminal.

5. device as claimed in claim 1, wherein, the rate calculations module is by traveling through each speed that sends to each terminal in described each terminal, if the speed in described each speed is less than or equal to the algorithm maximum rate and throughput corresponding to described speed is maximum throughput, then described speed is defined as iptimum speed.

6. the multicast based on WLAN (wireless local area network) in AP turns the method for clean culture, comprising:

Add up the power information of each terminal;

According to the success rate of unicast frame speed, calculate the iptimum speed that AP sends to each terminal;

Iptimum speed and multicast speed according to the rate calculations module is calculated are categorized as two-forty terminal and low rate terminal with terminal; For the low rate terminal, multicast mode is converted into mode of unicast; Power information according to power statistic module statistics copies multicast frame, and the frame after copying is sent to respectively each low rate terminal in all low rate terminals by mode of unicast; Wherein, multicast speed is the basic rate of selecting in from the basic rate that AP supports any one.

7. method as claimed in claim 6 wherein, for the two-forty terminal, keeps multicast mode constant.

8. method as claimed in claim 6, wherein, described power information comprises that the optimum receiving signal intensity of each terminal and AP are to the best strength of transmitted signals of each terminal.

9. method as claimed in claim 6, wherein, the step that terminal is categorized as two-forty terminal and low rate terminal comprises: when the iptimum speed of terminal during more than or equal to multicast speed, described terminal is categorized as the two-forty terminal; When the iptimum speed of terminal during less than multicast speed, described terminal is categorized as the low rate terminal.

10. method as claimed in claim 7, wherein, calculate the step that AP sends to the iptimum speed of each terminal and comprise:

The rate calculations module is by traveling through each speed that sends to each terminal in described each terminal, if the speed in described each speed is less than or equal to the algorithm maximum rate and throughput corresponding to described speed is maximum throughput, then described speed is defined as iptimum speed.