CN102170341A - Method and apparatus for data transmission - Google Patents
Method and apparatus for data transmission Download PDFInfo
- Publication number
- CN102170341A CN102170341A CN2011101004932A CN201110100493A CN102170341A CN 102170341 A CN102170341 A CN 102170341A CN 2011101004932 A CN2011101004932 A CN 2011101004932A CN 201110100493 A CN201110100493 A CN 201110100493A CN 102170341 A CN102170341 A CN 102170341A
- Authority
- CN
- China
- Prior art keywords
- blocks
- files
- sliding window
- information
- width
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Data Exchanges In Wide-Area Networks (AREA)
Abstract
The invention discloses a method and an apparatus for data transmission, belonging to the communication technical field. The method comprises: acquiring time values of information waiting for affirmation of each file block information in a sliding window at present scanning time; when the proportionality of file block receiving no affirmation information is small enough or the file block information with time values of information waiting for affirmation larger than an over-time value exists, removing the transmitted file block information from the window and loading the un-transmitted file block for immediate transmitting; and if the file block information with time values of information waiting for affirmation larger than the over-time value exists, adjusting the width of the sliding window and retransmitting the file block corresponding to the file block information. By centralizing the file blocks with possible overtime waiting for affirmation information in the window, the dependence on each file block in the window can be reduced, the case that new file blocks are not read and transmitted due to the waiting for small quantity of overtime packages in the window can be prevented, the file transmitting efficiency is substantially improved, thereby raising file block transmitting speed and saving occupied network resources.
Description
The application be Tencent Technology (Shenzhen) Co., Ltd. on 02 05th, 2009 application, application number be 200910008497.0, denomination of invention divides an application for the application for a patent for invention of " a kind of method and apparatus of transfer of data ".
Technical field
The present invention relates to communication technique field, particularly a kind of method and apparatus of transfer of data.
Background technology
Along with development of internet technology, network instant communication instrument (IM, Instant Messager) develops into today, accepted by most user, become the requisite Software tool of user, not only in amusement and recreation at ordinary times, and in user's work, used widely.Therefore, the user is to the ease for use of IM software, stability, and aspects such as fail safe have proposed higher requirement.Wherein, a kind of function that file transfer is supported as the network instant communication instrument has very important low level in the IM infrastructure service, and what how to transmit is faster more efficient, is a problem that needs study for a long period of time.
At present, realize that file transfer is to adopt based on UDP (User Datagram Protocol, User Datagram Protoco (UDP)) method of sliding window mechanism: transmit leg is with whole file waiting for transmission, be divided into a plurality of blocks of files, wherein, each blocks of files adopts file identification SEQ (Sequence, sequence) to carry out uniquely tagged, and SEQ is by increasing progressively distribution; Then, a plurality of contiguous file block identification SEQ information are recorded in the sliding window, and send SEQ information corresponding file piece successively, when the affirmation information of receiving the blocks of files that the recipient returns thinks that then this document piece successfully sends; When in the sliding window during the SEQ information-change of the minimum blocks of files that sends of success, sliding window moves (being equivalent to the file transfer progress upgrades) backward, read new not transmission blocks of files information and transmission simultaneously, this sliding window constantly slides backward like this, finish up to the transmission of All Files piece, then this document transmission success.
Because the unsteadiness of network, the reasons such as finiteness of the resource of carrying transmission, when in network, carrying out file transfer, can there be the situation of packet loss in various degree, therefore, prior art proposes a kind of loss recovery mechanism, wherein, transmit leg is after each blocks of files sends in sliding window, according to the moment that sends this document piece and the moment that receives the affirmation information of this document piece, calculate RTT (Round Trip Time, loop time) (being that blocks of files is from being issued to the time interval of receiving confirmation), calculate RTO (Retransmission Time-Out according to a plurality of RTT again, the overtime re-transmission time), after if certain blocks of files sends in the sliding window, the time of waiting for confirmation of receipt information surpasses RTO, think that then this document piece sends failure, need to retransmit, wherein, blocks of files is retransmitted the width that at first dwindles sliding window, empty sliding window, reading minimum several blocks of files of successful transmission then puts sliding window into and sends, when waiting the blocks of files of these repeating transmission to receive confirmation and moving window like this, the alternative document piece that old before sliding window sends also should have been received confirmation, thereby avoiding repeating sends.
The inventor is in realizing process of the present invention, find that there is following shortcoming and defect at least in above-mentioned prior art: on the one hand, the stand-by period of blocks of files is as long as surpass RTO, then transmit leg thinks that this document piece sends failure, need carry out the repeating transmission of blocks of files, and the stand-by period of blocks of files surpasses RTO, may be because the affirmation packets lost of recipient's feedback, be that recipient's reality has been received certain blocks of files, but because the affirmation information dropout of feedback, and cause transmit leg to think that this document piece sends failure, causes the repeating transmission of this document piece to be sent by mistake, influence transmission progress, wasted network transmission resource;
On the other hand, when carrying out the repeating transmission of blocks of files, need at first dwindle the width of sliding window, empty sliding window, carry out the not transmission of the blocks of files of success transmission again,, cause retransmission efficiency low owing to need empty sliding window; Owing to need dwindle the width of sliding window, particularly under the situation at unstable networks, the probability of retransmitting blocks of files becomes big, so occur and need become big to the probability of the adjustment of sliding window width, cause the continuous big ups and downs of window width, and then cause unnecessary overtime.
Summary of the invention
For file transfer is optimized, effectively improve the retransmission efficiency of blocks of files, the embodiment of the invention provides a kind of method and apparatus of transfer of data.Described technical scheme is as follows:
On the one hand, the embodiment of the invention provides a kind of method of transfer of data, and described method comprises:
Each blocks of files information in the transmit leg timing scan sliding window is obtained the current scanning wait acknowledge information time value of each blocks of files information constantly;
Obtain the overtime re-transmission time value of described sliding window;
When there is the blocks of files information of wait acknowledge information time value greater than overtime early warning value in described sliding window, then adjust the width of described sliding window, remove and send blocks of files information; Wherein, described overtime early warning value is less than overtime re-transmission time value;
Utilize sliding window behind the described adjustment width to read blocks of files corresponding file block message to be sent and send immediately;
The sliding window that utilization is adjusted behind the width is retransmitted blocks of files, and the blocks of files of described repeating transmission is the blocks of files information corresponding file piece of wait acknowledge information time value greater than overtime early warning value;
After the blocks of files information corresponding file piece that is positioned at primary importance in the sliding window behind the described adjustment width successfully sends, then the sliding window front portion behind the described adjustment width removes the blocks of files information that sent continuously, moves the sliding window behind the described adjustment width backward.
Wherein, the described overtime re-transmission time value of obtaining described sliding window comprises:
According to sliding window send blocks of files information corresponding file piece the moment, receive moment of the affirmation information of described blocks of files, calculate the loop time value of described blocks of files;
According to a plurality of loop time values, calculate overtime re-transmission time value.
Further, described method also comprises:
The described sliding window of described transmit leg timing scan obtains current scanning and does not successfully send the blocks of files number in the sliding window constantly;
The blocks of files number that sends when described success is less than preset value, then remove the blocks of files corresponding file block message that success sends in the described sliding window, read blocks of files corresponding file block message to be sent, and send the described blocks of files information corresponding file piece that reads.
Wherein, when described transmit leg need be adjusted the sliding window width, described method also comprised:
Obtain the number of the blocks of files that average per second transmission is successful in the Preset Time;
According to the described number of obtaining, obtain the packet loss coefficient;
Obtain average loop time value in the described Preset Time;
According to the described number of obtaining, described average loop time value and described packet loss coefficient, calculate reasonable window width;
According to the reasonable window width that calculates, adjusted sliding window width is set.
Further, after described sending direction recipient sent current file block message corresponding file piece, described method also comprised:
After described recipient receives described blocks of files, return confirmation to described transmit leg, the minimum of carrying described recipient in the described confirmation does not receive successful blocks of files information to maximum each blocks of files information and the state indication that receives between the successful blocks of files information.
After the sending direction recipient sent current file block message corresponding file piece, described method also comprised:
After described recipient receives described blocks of files, return confirmation to described transmit leg, the minimum of carrying described recipient in the described confirmation does not receive successful blocks of files information to maximum each blocks of files information and the state indication that receives between the successful blocks of files information.
On the one hand, the embodiment of the invention also provides a kind of method of transfer of data again, and described method comprises:
Transmit leg timing scan sliding window obtains current scanning and does not successfully send the blocks of files number in the sliding window constantly;
The blocks of files number that sends when described success is less than preset value, then remove the blocks of files corresponding file block message that success sends in the described sliding window, read blocks of files corresponding file block message to be sent, and send the described blocks of files information corresponding file piece that reads.
Further, described method also comprises:
Each blocks of files information in the described transmit leg timing scan sliding window is obtained the current scanning wait acknowledge information time value of each blocks of files information constantly;
Obtain the overtime re-transmission time value of described sliding window;
When there is the blocks of files information of wait acknowledge information time value greater than overtime early warning value in described sliding window, then adjust the width of described sliding window, remove and send blocks of files information; Wherein, described overtime early warning value is less than overtime re-transmission time value;
Utilize sliding window behind the described adjustment width to read blocks of files corresponding file block message to be sent and send immediately;
The sliding window that utilization is adjusted behind the width is retransmitted blocks of files, and the blocks of files of described repeating transmission is the blocks of files information corresponding file piece of described wait acknowledge information time value greater than overtime early warning value;
After the blocks of files information corresponding file piece that is positioned at primary importance in the sliding window behind the described adjustment width successfully sends, then the sliding window front portion behind the described adjustment width removes the blocks of files information that sent continuously, moves the sliding window behind the described adjustment width backward.
When needs were adjusted the sliding window width, described method comprised:
Obtain the number of the blocks of files that average per second transmission is successful in the Preset Time;
According to the described number of obtaining, obtain the packet loss coefficient;
Obtain average loop time value in the described Preset Time;
According to the described number of obtaining, described average loop time value and described packet loss coefficient, calculate reasonable window width;
According to the reasonable window width that calculates, adjusted sliding window width is set.
After described sending direction recipient sent current file block message corresponding file piece, described method also comprised:
After described recipient receives described blocks of files, return confirmation to described transmit leg, the minimum of carrying described recipient in the described confirmation does not receive successful blocks of files information to maximum each blocks of files information and the state indication that receives between the successful blocks of files information.
Wherein, described preset value value is 1/3rd of a described sliding window width.
On the one hand, the embodiment of the invention also provides a kind of method of transfer of data again, and when needs were adjusted the sliding window width, described method comprised:
Obtain the number of the blocks of files that average per second transmission is successful in the Preset Time;
According to the described number of obtaining, obtain the packet loss coefficient;
Obtain average loop time value in the described Preset Time;
According to the described number of obtaining, described average loop time value and described packet loss coefficient, calculate reasonable window width;
According to the reasonable window width that calculates, adjusted sliding window width is set.
On the one hand, the embodiment of the invention also provides a kind of method of transfer of data again, and after the sending direction recipient sent current file block message corresponding file piece, described method comprised:
After described recipient receives described blocks of files, return confirmation to described transmit leg, the minimum of carrying described recipient in the described confirmation does not receive successful blocks of files information to maximum each blocks of files information and the state indication that receives between the successful blocks of files information.
On the one hand, the embodiment of the invention also provides a kind of device of transfer of data again, and described device comprises:
Acquisition module is used for each the blocks of files information in the timing scan sliding window, obtains the current scanning wait acknowledge information time value of each blocks of files information constantly; Also be used to obtain the overtime re-transmission time value of described sliding window;
Retransmit module is used for having the blocks of files information of wait acknowledge information time value greater than overtime early warning value when described sliding window, then adjusts the width of described sliding window, and wherein, described overtime early warning value is less than overtime re-transmission time value; From described sliding window, remove and send blocks of files information, utilize sliding window behind the described adjustment width to read blocks of files corresponding file block message to be sent and send immediately; The sliding window that utilization is adjusted behind the width is retransmitted blocks of files, and the blocks of files of described repeating transmission is the blocks of files information corresponding file piece of wait acknowledge information time value greater than overtime early warning value;
Processing module is used for after the blocks of files information corresponding file piece that is positioned at primary importance in the described sliding window successfully sends, and then removes the continuous information of transmission blocks of files from described sliding window front portion, moves described sliding window backward.
On the one hand, the embodiment of the invention also provides a kind of device of transfer of data again, and described device comprises:
Scan module is used for the timing scan sliding window, obtains current scanning and does not successfully send the blocks of files number in the sliding window constantly;
Retransmit module, the blocks of files number that is used for sending when described not success is less than preset value, then remove the blocks of files corresponding file block message that success sends in the described sliding window, read blocks of files corresponding file block message to be sent, and send the described blocks of files information corresponding file piece that reads.
On the one hand, the embodiment of the invention also provides a kind of data transmission device again, and described device comprises:
Receiver module is used to receive current file block message corresponding file piece;
Sending module, be used to return the affirmation information of described current file block message corresponding file piece, the minimum of carrying described recipient in the described confirmation does not receive successful blocks of files information to maximum each blocks of files information and the state indication that receives between the successful blocks of files information.
On the one hand, the embodiment of the invention also provides a kind of data transmission device again, and when needs carried out the sliding window adjustment, described device comprised:
Acquisition module is used to obtain the number that the interior average per second of Preset Time sends successful blocks of files; Also be used to obtain average loop time value in the described Preset Time;
Computing module is used for calculating reasonable window width according to described number of obtaining and described average loop time value;
Adjusting module is used for according to the reasonable window width that calculates adjusted sliding window width being set.
The beneficial effect of the technical scheme that the embodiment of the invention provides is:
By being set, overtime early warning value carries out timeout treatment, the efficient that sends file improves greatly, improved the transmission speed of blocks of files, shared Internet resources have been saved, when the method that the embodiment of the invention is provided is applied to immediate communication tool, improved user experience, increased the viscosity of user the use of this instrument.
Description of drawings
In order to be illustrated more clearly in the embodiment of the invention or technical scheme of the prior art, to do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below, apparently, accompanying drawing in describing below only is some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is the method flow schematic diagram of the transfer of data that provides of the embodiment of the invention 1.
Fig. 2 is the method flow schematic diagram of the transfer of data that provides of the embodiment of the invention 2.
Fig. 3 is the method flow schematic diagram of the transfer of data that provides of the embodiment of the invention 3.
Fig. 4 is that recipient's progress that the embodiment of the invention 3 provides shows schematic diagram.
Fig. 5 is the method flow schematic diagram of the transfer of data that provides of the embodiment of the invention 4.
Fig. 6 is the device schematic diagram of the transfer of data that provides of the embodiment of the invention 5.
Fig. 7 is the device schematic diagram of the transfer of data that provides of the embodiment of the invention 6.
Fig. 8 is the device schematic diagram of the transfer of data that provides of the embodiment of the invention 7.
Fig. 9 is the device schematic diagram of the transfer of data that provides of the embodiment of the invention 8.
Embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, embodiment of the present invention is described further in detail below in conjunction with accompanying drawing.
For file transfer is optimized, improve the retransmission efficiency of blocks of files, avoid the waste of network transmission resource, and effectively avoid the continuous big ups and downs of window width, the embodiment of the invention provides a kind of method of transfer of data, this method thes contents are as follows: each the blocks of files information in the timing scan sliding window, obtain the current scanning wait acknowledge information time value of each blocks of files information constantly; Obtain the overtime re-transmission time value of sliding window; When there is the blocks of files information of wait acknowledge information time value greater than overtime early warning value in sliding window, then adjust the width of sliding window, remove from sliding window and sent blocks of files information, the sliding window that utilization is adjusted behind the width reads blocks of files corresponding file block message to be sent and transmission immediately; The sliding window that utilization is adjusted behind the width is retransmitted the blocks of files information corresponding file piece of wait acknowledge information time value greater than overtime early warning value; Wherein, overtime early warning value is less than overtime re-transmission time value; After the blocks of files information corresponding file piece that is positioned at primary importance in the sliding window after adjusting width successfully sends, then remove the blocks of files information that sent continuously, move the sliding window of adjusting behind the width backward from the sliding window front portion of adjusting behind the width.For the method that the invention described above embodiment is provided is elaborated, see also following description:
The embodiment of the invention provides a kind of method of transfer of data, for convenience of explanation, it is that example describes that present embodiment sends file XX with the sending direction recipient, wherein, according to the size that transmit leg and recipient shook hands and decide through consultation before transmission, this file XX waiting for transmission is divided into a plurality of blocks of files, the equal size of each blocks of files wherein, each blocks of files is used the unique mark that carries out of blocks of files mark SEQ, and the size of SEQ increases progressively distribution.Referring to table 1, the SEQ signal table of the blocks of files that provides for the embodiment of the invention.
Table 1
| File XX | First | Second | The 3rd | ...... | The N-1 piece | The |
| SEQ | ||||||
| 1 | 2 | 3 | ...... | N-1 | N |
As shown in table 1, this document XX is divided and obtains N blocks of files, and this document XX is just sent to the recipient by sliding window, and referring to Fig. 2, this method thes contents are as follows:
Step 101: each the blocks of files information in the timing scan sliding window, obtain the current scanning wait acknowledge information time of each blocks of files information constantly.
Wherein,, set the time cycle of timing scan, preferably, set every 50ms run-down according to the concrete needs such as characteristics of Network Transmission.
Suppose that at current scanning moment Tc, have 5 blocks of files in the sliding window, the SEQ of each blocks of files is respectively SEQ11, SEQ12, SEQ13, SEQ14 and SEQ15, wherein,
Constantly (T11＜Tc) send is waiting for that reception returns confirmation from the recipient to blocks of files SEQ11 at T11;
Constantly (T12＜Tc) send is waiting for that reception returns confirmation from the recipient to blocks of files SEQ12 at T12;
Constantly (T13＜Tc) send is waiting for that reception returns confirmation from the recipient to blocks of files SEQ13 at T13;
Blocks of files SEQ14 also sends at this Tc constantly;
Blocks of files SEQ15 also sends at this Tc constantly.
Then, the delivery time according to each file in current scanning moment Tc and the sliding window gets access to each blocks of files wait acknowledge information time value corresponding.
That is, at current scanning moment Tc, the wait acknowledge information time that gets access to blocks of files SEQ11 is Tc-T11;
In like manner, at current scanning moment Tc, the wait acknowledge information time that gets access to blocks of files SEQ12 is Tc-T12;
In like manner, at current scanning moment Tc, the wait acknowledge information time that gets access to blocks of files SEQ13 is Tc-T13.
Step 102: judge whether sliding window exists the blocks of files information of wait acknowledge information time greater than overtime early warning value, if then execution in step 103, otherwise, execution in step 105.
Wherein, above-mentioned overtime early warning value is set as required, but will guarantee this overtime early warning value less than overtime re-transmission time RTO value, and wherein, the obtain manner of RTO value is as follows:
At first, transmit leg is after each blocks of files sends in sliding window, can be according to the moment that sends this document piece and the moment that receives the affirmation information of this document piece that the recipient returns, calculate the loop time RTT (being that blocks of files is from being issued to the time interval of receiving confirmation) of each blocks of files;
Then, according to a plurality of RTT, calculate the overtime re-transmission time RTO that this file sends.For example, a plurality of RTT are got average and obtain RTO.
By the substantive test experiment, preferably, it is as follows that above-mentioned overtime early warning value is provided with value:
RTT value * the 1.2+100ms of the maximum that occurs in overtime early warning value=30s.
In addition, this overtime early warning value be provided with value can also for
RTT value+the 200ms of the maximum that occurs in overtime early warning value=30s.Present embodiment is not done any restriction to this.
Step 103: dwindle the sliding window width, retransmit the blocks of files information corresponding file piece of wait acknowledge information time greater than overtime early warning value.
Wherein, with sliding window reduced width before, the above-mentioned wait acknowledge information time that obtains is retransmitted greater than the blocks of files information corresponding file piece of overtime early warning value, for example, still with above-mentioned example explanation, before, there are 5 blocks of files information (SEQ11 in the sliding window, SEQ12, SEQ13, SEQ14 and SEQ15), the width of supposing this corresponding sliding window is 5, then know SEQ11 by above-mentioned steps 101 to 103, SEQ12, SEQ13, SEQ14 need retransmit, and in order to dwindle packet loss as far as possible, then the width with this sliding window is reduced into 4 by 5, then with SEQ11, SEQ12, SEQ13, SEQ14 corresponding file piece is retransmitted.
Step 104: after the blocks of files information respective file piece of primary importance in the sliding window successfully sends, then remove the blocks of files information that has sent continuously, move this sliding window more backward from the sliding window front portion.
Still with the above-mentioned example that is exemplified as, SEQ11, SEQ12, SEQ13, SEQ14 are arranged in order in the sliding window after dwindling, and after the SEQ11 that is positioned at primary importance sends successfully, then remove this SEQ11 in sliding window, move this sliding window backward, read SEQ15.
Step 105: do not carry out action, continue to wait for scanning next time arrival constantly.
To sum up, by above-mentioned steps 101-104, as long as it is suitable that above-mentioned overtime early warning value is set, the blocks of files that then above-mentioned overtime early warning is retransmitted all is the blocks of files that real overtime needs are retransmitted, test by experiment, the blocks of files of retransmitting by the said method early warning all is real overtime blocks of files, the method that the embodiment of the invention provides, compare with prior art by carrying out overtime early warning processing, owing to do not need to empty and read the blocks of files that success sends behind the sliding window again and heavily send, transmitting efficiency improves greatly, and then improved the transmission speed of blocks of files, saved shared Internet resources, when this method is applied to immediate communication tool, improved user experience, increased the viscosity of user the use of this instrument.
Embodiment 2
When existing packet loss or network delay unstable, the sliding window content is prone to and does not successfully send the scattered situation about being distributed in the sliding window of blocks of files, cause window to slide backward smoothly, the embodiment of the invention provides a kind of method of transfer of data, this method thes contents are as follows: the timing scan sliding window, obtain current scanning and successfully do not send the blocks of files number in the sliding window constantly; The blocks of files number that sends when success then removes the blocks of files corresponding file block message that success sends in the sliding window less than preset value, reads blocks of files corresponding file block message to be sent, and sends the blocks of files information corresponding file piece that reads.Referring to Fig. 2, the method that the embodiment of the invention provides specifically comprises:
Step 201: the timing scan sliding window, obtain current scanning constantly, successfully do not send the blocks of files number in the sliding window.
Wherein, the setting scan period is preferably 50ms.
Step 202: judge the blocks of files number of the not success transmission that scanning obtains, whether less than preset value, if then execution in step 203; Otherwise, execution in step 204.
Wherein,, set this preset value, preferably be set to 1/3 of sliding window width according to the characteristics of Network Transmission.Correspondingly, judge that the not successful blocks of files number that sends that obtains in scanning scanning constantly is less relatively, promptly less than window width 1/3.
For example, in Td scanning constantly, suppose that the blocks of files information that exists in this sliding window is as follows:
Constantly (T20＜Td) send is waiting for that reception returns confirmation from the recipient to blocks of files SEQ20 at T20;
Blocks of files SEQ21 is at the T21 moment (T21＜Td) successfully send;
(T22＜Td) sends blocks of files SEQ22 constantly, is waiting for that reception returns confirmation from the recipient at T22;
(T23＜Td) sends blocks of files SEQ23 constantly, is waiting for that reception returns confirmation from the recipient at T23 at this
Blocks of files SEQ24 is at the T24 moment (T21＜Td) successfully send;
Constantly (T21＜Td) send is waiting for that reception returns confirmation from the recipient to blocks of files SEQ25 at T25;
Constantly (T26＜Td) send is waiting for that reception returns confirmation from the recipient to blocks of files SEQ26 at T26;
Blocks of files SEQ27 is at the T27 moment (T27＜Td) successfully send;
......
Blocks of files SEQ33 is at the T33 moment (T33＜Td) successfully send;
......
Blocks of files SEQ49 is at the T49 moment (T49＜Td) successfully send;
Promptly, the width of this sliding window that is provided with is 30, at this scanning moment Td, the not successful blocks of files that sends is SEQ20, SEQ22, SEQ23, SEQ25, SEQ26 in this sliding window, all the other each blocks of files successfully send, because the number of the blocks of files that the not success that scanning obtains sends is 5 less than 1/3 of window width 30, then needs to carry out following step 203.
Step 203: remove the blocks of files information that success sends in this sliding window, move this sliding window backward, and read the blocks of files information of blocks of files to be sent.
Wherein, by removing the blocks of files information that success sends in this sliding window, move this sliding window backward, and read the blocks of files information of blocks of files to be sent, realization is concentrated the purpose that sends to not sending successful blocks of files, and has quickened moving of sliding window.
Step 204: do not carry out action.
To sum up, by above-mentioned steps 201-204, by the method that the blocks of files information of success transmission is concentrated, quicken sliding window and moved, improved transmitting efficiency greatly, and then improved the transmission speed of blocks of files, shared Internet resources have been saved, when this method is applied to immediate communication tool, improved user experience, increased the viscosity of user the use of this instrument.
Wherein, the method that this embodiment 2 is provided is used in combination with the method that embodiment 1 provides, and can quicken sliding window further and move, and has improved transmitting efficiency greatly, and then has improved the transmission speed of blocks of files, optimizes the UDP file transfer.
Embodiment 3
When network carries out the transmission of file, may be to lose and cause blocks of files to be retransmitted owing to the blocks of files that transmit leg sends, and owing to the reasons such as unsteadiness of network, also might be because the affirmation packets lost of recipient's feedback, be that recipient's reality has been received certain blocks of files, but because the affirmation information dropout of feedback, and allow transmit leg think that this document piece sends failure by mistake, cause the repeating transmission of this document piece, therefore, in order effectively to avoid the appearance of this situation, improve the file transmitting efficiency, save network transmission resource, the embodiment of the invention provides a kind of method of transfer of data, after the sending direction recipient sends current file block message corresponding file piece, method comprises: after the recipient received blocks of files, to the affirmation information that transmit leg returns, the minimum of carrying the recipient in the confirmation did not receive successful blocks of files information to maximum each blocks of files information and the state indication that receives between the successful blocks of files information.Referring to Fig. 3, the embodiment of the invention provides following method:
Step 301: the recipient is after receiving blocks of files, the information that in the affirmation information that transmit leg returns, adds the adjacent files piece of this blocks of files that receives, wherein, this adjacent files block message comprises: the minimum blocks of files information that reception is successful is to maximum each blocks of files information and the status indication indication that receives between the successful blocks of files information.
Wherein, minimum receives successful blocks of files information, is meant the unmarked blocks of files of recipient SEQ minimum; Maximum receives successful blocks of files information, is meant the piece of tab file of recipient SEQ maximum, and wherein, so-called mark is meant the indication of the accepting state of expression this document piece, for example, uses 1 expression to receive; Use 0 expression to receive,, then represent whole file to receive, in like manner,, then represent whole blocks of files transmission to finish if transmit leg All Files piece is mark if all blocks of files of recipient is mark.
For convenience of explanation, suppose that the recipient receives blocks of files SEQ13, in fact the blocks of files of SEQ9, SEQ12 is because transmit leg sends packet loss, cause the recipient successfully not receive, that is be unlabelled blocks of files at recipient SEQ9 and SEQ12, and SEQ9 is the minimum successful blocks of files that do not receive; And, SEQ1-SEQ8, SEQ10 are the blocks of files that success receives, because SEQ13 receives successfully, then SEQ13 is the maximum successful blocks of files that receives, when then the receive direction transmit leg returns the affirmation information of this document piece SEQ13, in confirmation, add minimum do not receive successful blocks of files SEQ9 and maximum each blocks of files information and the status indication indication that receives between the successful blocks of files SEQ13.Promptly carry at least in this confirmation: SEQ9 (0); SEQ10 (1); SEQ11 (1); SEQ12 (0); SEQ13 (1).Wherein, the state of (0) expression this document piece is that the recipient does not receive; (1) state of expression this document piece is that the recipient successfully receives.
Step 302: after transmit leg receives the affirmation information that the recipient returns, read current do not send and do not receive confirmation blocks of files blocks of files information and send.
Still with above-mentioned example, after transmit leg receives the affirmation information that the recipient returns at SEQ13, do not receive successful blocks of files SEQ9 and maximum each blocks of files information and the status indication indication that receives between the successful blocks of files SEQ13 according to the minimum of carrying in this confirmation, know that the successful blocks of files of the minimum at present not reception of recipient is SEQ9, and the successful blocks of files of maximum reception is SEQ13, then correspondingly, retransmit SEQ9 corresponding file piece to the recipient.Continue, after the recipient receives SEQ9 corresponding file piece, when transmit leg returns affirmation information at this SEQ9, add minimumly receiving successful blocks of files information SEQ10 and maximum each blocks of files information and the status indication that receives between the successful blocks of files SEQ13 indicated this moment.
Referring to Fig. 4, the recipient's progress that provides for the embodiment of the invention shows schematic diagram, and at T1 constantly, recipient's reception progress rests on SEQ8 because SEQ9 does not receive so show the reception indication; And at T2 constantly,, show that receiving indication rests on SEQ11 constantly by the method that the embodiment of the invention provides; In like manner, show that indicating progress continues reach successively, shows up to whole file to receive.
Wherein, above-mentionedly only be the example explanation, through test, the data of carry-on maximum 100byte byte-sized in this confirmation that the embodiment of the invention provides, because it is 1bit that status indication is indicated shared size, therefore, probably can carry the information of 800 adjacent files pieces in the confirmation at most; And, almost can ignore the influence of speed or efficient by repeatedly testing the validation confirmation information packet loss repeatedly.
In sum, the method that the embodiment of the invention provides, by carrying the mode of redundant validation information in the confirmation, effectively avoid because the affirmation information dropout that the recipient returns, the repeating transmission of the blocks of files that the transmit leg that causes has received the recipient improves the file transmitting efficiency, saves network transmission resource.
Wherein, the method that present embodiment 3 is provided is in conjunction with the foregoing description 1, each blocks of files information in embodiment 1 described step 101 in the timing scan sliding window, obtain in the wait acknowledge information time process of current each blocks of files information of the scanning moment, the method that provides by the embodiment of the invention, guarantee that transmit leg knows the information of the blocks of files that has sent to the recipient accurately, effectively prevent the repeating transmission of blocks of files.Or in conjunction with the foregoing description 2, at the related step 201 timing scan sliding window of embodiment 2, obtain current scanning constantly, successfully do not send in the blocks of files number process in the sliding window, the method that provides by the embodiment of the invention, guarantee that transmit leg knows the information of the blocks of files that has sent to the recipient accurately, promptly successfully do not send blocks of files in the sliding window and be the unreceived blocks of files of recipient really, effectively avoid the repeating transmission of blocks of files.Can improve the file transmitting efficiency once more, save network transmission resource, optimize the UDP file transfer; In like manner, the method that the embodiment of the invention 3 is provided is used in combination with embodiment 1 and embodiment 2 and can improves file transmitting efficiency, saving network transmission resource more further, optimization UDP file transfer.
Embodiment 4
Because when Network Transmission, need be to the real-time adjustment of sliding window, particularly, under the situation at unstable networks, the probability of retransmitting blocks of files becomes big, so occur and to become big to the probability of the adjustment of sliding window width, cause the continuous big ups and downs of window width, and then cause unnecessary overtimely, the embodiment of the invention provides a kind of method of transfer of data, when needs were adjusted the sliding window width, this method comprised:
Obtain the number of the blocks of files that average per second transmission is successful in the Preset Time; According to the number of obtaining, obtain the packet loss coefficient; Obtain average loop time value in the Preset Time; According to the number of obtaining, average loop time value and packet loss coefficient, calculate reasonable window width; According to the reasonable window width that calculates, adjusted sliding window width is set.Referring to Fig. 5, this method thes contents are as follows:
Step 401: obtain the number of the blocks of files that average per second transmission is successful in the Preset Time,, obtain the packet loss coefficient according to this number;
Step 402: obtain average loop time RTT value in this Preset Time;
Step 403:, calculate reasonable window width according to above-mentioned number of obtaining and RTT value.
Step 404: when carrying out the sliding window adjustment,, adjusted sliding window width is set according to the reasonable window width that calculates.
Wherein, preferably, Preset Time is 10s, and then rationally the account form of window width is as follows:
Rationally the average per second of window width=Preset Time (10s) sends successful blocks of files number * average during this period of time RTT value (s of unit) * (1+ packet loss coefficient weighted value); Wherein, when packet loss was 0, above-mentioned reasonable window width was that the average per second of Preset Time (10s) sends successful blocks of files number * average during this period of time RTT value (s of unit).
Correspondingly, will be subjected to the restriction of this reasonable window width that calculates to the sliding window width adjustment, preferably, the width size after the sliding window width adjustment is restricted in the reasonable window width positive and negative 5.
In sum, the method that the embodiment of the invention provides, by predicting reasonable window width, thus the amplitude of the width adjustment of limit slippage window, thus the window width fluctuation reduced, reduce the harmful effect that fluctuation causes.
The method that method that present embodiment is provided and the various embodiments described above provide is used in combination, and for example when method that the embodiment of the invention 1 provides is used in combination, adjusts the width of sliding window by control, reduces to fluctuate to such an extent that optimize the better effect of UDP file transfer.Owing to reduce the window width fluctuation, reduce the harmful effect that fluctuation causes, therefore improve transmitting efficiency and improve greatly, and then improved the transmission speed of blocks of files, saved shared Internet resources, optimize the UDP file transfer.
To sum up, the method that the invention described above embodiment provides, can use separately, can also combination in any use, thereby obtain the purpose that the UDP file transfer is optimized in arrival once more that is used in combination by method, preferably, the method that the invention described above embodiment 1-4 is provided is used in combination, and can obtain the better effect of optimizing the UDP file transfer further.
The method that provides with the foregoing description 1 is corresponding, and the embodiment of the invention provides a kind of device of transfer of data, and referring to Fig. 6, device comprises:
Acquisition module is used for each the blocks of files information in the timing scan sliding window, obtains the current scanning wait acknowledge information time value of each blocks of files information constantly; Also be used to obtain the overtime re-transmission time value of sliding window;
Retransmit module, be used for having the blocks of files information of wait acknowledge information time value greater than overtime early warning value when sliding window, then adjust the width of sliding window, remove from sliding window and sent blocks of files information, the sliding window that utilization is adjusted behind the width reads blocks of files corresponding file block message to be sent and transmission immediately; The sliding window that utilization is adjusted behind the width is retransmitted the blocks of files information corresponding file piece of wait acknowledge information time value greater than overtime early warning value; Wherein, overtime early warning value is less than overtime re-transmission time value;
Processing module is used for then removing the continuous information of transmission blocks of files, mobile backward sliding window from the sliding window front portion after the blocks of files information corresponding file piece that is positioned at primary importance in the sliding window successfully sends.
Wherein, during practical application, when above-mentioned retransmit module is adjusted the width of sliding window, be generally the width that dwindles this sliding window.
The device that the embodiment of the invention provides, compare with prior art by carrying out overtime early warning processing, owing to do not need to empty and read the blocks of files that success sends behind the sliding window again and heavily send, transmitting efficiency improves greatly, and then improved the transmission speed of blocks of files, saved shared Internet resources, when this method is applied to immediate communication tool, improved user experience, increased the viscosity of user the use of this instrument.
The method that provides with the foregoing description 2 is corresponding, and the embodiment of the invention provides a kind of device of transfer of data, and referring to Fig. 7, device comprises:
Scan module is used for the timing scan sliding window, obtains current scanning and does not successfully send the blocks of files number in the sliding window constantly;
Retransmit module, the blocks of files number that is used for not success transmission is less than preset value, then remove the blocks of files corresponding file block message that success sends in the sliding window, read blocks of files corresponding file block message to be sent, and send the blocks of files information corresponding file piece that reads.
The device that the embodiment of the invention provides, by the method that the blocks of files information of success transmission is concentrated, having quickened sliding window moves, improved transmitting efficiency greatly, and then improved the transmission speed of blocks of files, saved shared Internet resources, when this method is applied to immediate communication tool, improved user experience, increased the viscosity of user the use of this instrument.
The method that provides with the foregoing description 3 is corresponding, and the embodiment of the invention provides a kind of device of transfer of data, and referring to Fig. 8, described device comprises:
Receiver module is used to receive current file block message corresponding file piece;
Sending module, be used to return the affirmation information of described current file block message corresponding file piece, the minimum of carrying described recipient in the described confirmation does not receive successful blocks of files information to maximum each blocks of files information and the state indication that receives between the successful blocks of files information.
In sum, the device that the embodiment of the invention provides, by carrying the mode of redundant validation information in the confirmation, effectively avoid because the affirmation information dropout that the recipient returns, the repeating transmission of the blocks of files that the transmit leg that causes has received the recipient improves the file transmitting efficiency, saves network transmission resource.
The method that provides with the foregoing description 4 is corresponding, and the embodiment of the invention provides a kind of device of transfer of data, and when needs carried out the sliding window adjustment, referring to Fig. 8, described device comprised:
Acquisition module is used to obtain the number that the interior average per second of Preset Time sends successful blocks of files; Also be used to obtain average loop time value in the described Preset Time;
Computing module is used for calculating reasonable window width according to described number of obtaining and described average loop time value;
Adjusting module is used for according to the reasonable window width that calculates adjusted sliding window width being set.
In sum, the device that the embodiment of the invention provides, by predicting reasonable window width, thus the amplitude of the width adjustment of limit slippage window, thus the window width fluctuation reduced, reduce the harmful effect that fluctuation causes.
Similar with the compound mode of method embodiment, the device that the invention described above embodiment provides, can use separately, can also combination in any use, thereby obtain the purpose that the UDP file transfer is optimized in arrival once more that is used in combination by each device, preferably, for example the device that the invention described above embodiment 5-8 is provided is used in combination, and can obtain the better effect of optimizing the UDP file transfer.
The device that the embodiment of the invention provides carries out timeout treatment by overtime early warning value is set, and the efficient that sends file improves greatly, has improved the transmission speed of blocks of files, has saved shared Internet resources; By the method that the blocks of files information of not success transmission is concentrated, quickened sliding window to move, improved transmitting efficiency greatly; And, by carrying the mode of redundant validation information in the confirmation, effectively avoid because the affirmation information dropout returned of recipient, the repeating transmission of the blocks of files that the transmit leg that causes has received the recipient improves the file transmitting efficiency, saves network transmission resource; By predicting reasonable window width, thus the amplitude of the width adjustment of limit slippage window, thus reduce the window width fluctuation, reduce the harmful effect that fluctuation causes.When the device that the embodiment of the invention is provided is applied to immediate communication tool, improved user experience, increased the viscosity of user the use of this instrument.
It will be appreciated by those skilled in the art that accompanying drawing is the schematic diagram of a preferred embodiment, module in the accompanying drawing or flow process might not be that enforcement the present invention is necessary.
It will be appreciated by those skilled in the art that the module in the device among the embodiment can be distributed in the device of embodiment according to the embodiment description, also can carry out respective change and be arranged in the one or more devices that are different from present embodiment.The module of the foregoing description can be merged into a module, also can further split into a plurality of submodules.
The invention described above embodiment sequence number is not represented the quality of embodiment just to description.
Part steps in the embodiment of the invention can utilize software to realize that corresponding software programs can be stored in the storage medium that can read, as CD or hard disk etc.
The above only is preferred embodiment of the present invention, and is in order to restriction the present invention, within the spirit and principles in the present invention not all, any modification of being done, is equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (8)
1. the method for a transfer of data is characterized in that, described method comprises:
Each blocks of files information in the transmit leg timing scan sliding window is obtained the current scanning wait acknowledge information time value of each blocks of files information constantly;
Obtain the overtime re-transmission time value of described sliding window;
When there is the blocks of files information of wait acknowledge information time value greater than overtime early warning value in described sliding window, then adjust the width of described sliding window, remove and send blocks of files information; Wherein, described overtime early warning value is less than overtime re-transmission time value;
Utilize sliding window behind the described adjustment width to read blocks of files corresponding file block message to be sent and send immediately;
The sliding window that utilization is adjusted behind the width is retransmitted blocks of files, and the blocks of files of described repeating transmission is the blocks of files information corresponding file piece of wait acknowledge information time value greater than overtime early warning value;
After the blocks of files information corresponding file piece that is positioned at primary importance in the sliding window behind the described adjustment width successfully sends, then the sliding window front portion behind the described adjustment width removes the blocks of files information that sent continuously, moves the sliding window behind the described adjustment width backward;
Wherein, when described transmit leg need be adjusted the sliding window width, obtain the number of the blocks of files that average per second transmission is successful in the Preset Time; According to the described number of obtaining, obtain the packet loss coefficient; Obtain average loop time value in the described Preset Time; According to the described number of obtaining, described average loop time value and described packet loss coefficient, calculate reasonable window width, wherein, described reasonable window width=described number of obtaining * described average loop time value * (weighted value of the described packet loss coefficient of 1+); According to the reasonable window width that calculates, adjusted sliding window width is set.
2. the method for claim 1 is characterized in that, the described overtime re-transmission time value of obtaining described sliding window comprises:
According to sliding window send blocks of files information corresponding file piece the moment, receive moment of the affirmation information of described blocks of files, calculate the loop time value of described blocks of files;
According to a plurality of loop time values, calculate overtime re-transmission time value.
3. the method for claim 1 is characterized in that, described method also comprises:
The described sliding window of described transmit leg timing scan obtains current scanning and does not successfully send the blocks of files number in the sliding window constantly;
The blocks of files number that sends when described success is less than preset value, then remove the blocks of files corresponding file block message that success sends in the described sliding window, read blocks of files corresponding file block message to be sent, and send the described blocks of files information corresponding file piece that reads.
4. as claim 1 or 3 described methods, it is characterized in that after described sending direction recipient sent current file block message corresponding file piece, described method also comprised:
After described recipient receives described blocks of files, return confirmation to described transmit leg, the minimum of carrying described recipient in the described confirmation does not receive successful blocks of files information to maximum each blocks of files information and the state indication that receives between the successful blocks of files information.
5. the device of a transfer of data is characterized in that, described device comprises:
Acquisition module is used for each the blocks of files information in the transmit leg timing scan sliding window, obtains the current scanning wait acknowledge information time value of each blocks of files information constantly; Also be used to obtain the overtime re-transmission time value of described sliding window;
First retransmit module is used for having the blocks of files information of wait acknowledge information time value greater than overtime early warning value when described sliding window, and then described transmit leg is adjusted the width of described sliding window, and wherein, described overtime early warning value is less than overtime re-transmission time value; From described sliding window, remove and send blocks of files information, utilize sliding window behind the described adjustment width to read blocks of files corresponding file block message to be sent and send immediately; The sliding window that utilization is adjusted behind the width is retransmitted blocks of files, and the blocks of files of described repeating transmission is the blocks of files information corresponding file piece of wait acknowledge information time value greater than overtime early warning value;
Processing module is used for after the blocks of files information corresponding file piece that is positioned at primary importance in the described sliding window successfully sends, and then described transmit leg removes the continuous information of transmission blocks of files from described sliding window front portion, moves described sliding window backward;
Wherein, when described retransmit module is used to adjust the sliding window width, specifically be used to obtain the number of the blocks of files that average per second transmission is successful in the Preset Time; According to the described number of obtaining, obtain the packet loss coefficient; Obtain average loop time value in the described Preset Time; According to the described number of obtaining, described average loop time value and described packet loss coefficient, calculate reasonable window width, wherein, described reasonable window width=described number of obtaining * described average loop time value * (weighted value of the described packet loss coefficient of 1+); According to the reasonable window width that calculates, adjusted sliding window width is set.
6. device as claimed in claim 5, it is characterized in that, when described acquisition module is used to obtain the overtime re-transmission time value of described sliding window, specifically be used for according to sliding window send blocks of files information corresponding file piece the moment, receive moment of the affirmation information of described blocks of files, calculate the loop time value of described blocks of files; According to a plurality of loop time values, calculate overtime re-transmission time value.
7. device as claimed in claim 5 is characterized in that, described device also comprises:
Scan module is used for the described sliding window of described transmit leg timing scan, obtains current scanning and does not successfully send the blocks of files number in the sliding window constantly;
Second retransmit module, the blocks of files number that is used for sending when described not success is less than preset value, then described transmit leg removes the blocks of files corresponding file block message that success sends in the described sliding window, read blocks of files corresponding file block message to be sent, and send the described blocks of files information corresponding file piece that reads.
8. as claim 5 or 6 described devices, it is characterized in that described device also comprises:
Receiver module is used for the recipient and receives the current file block message corresponding file piece that described transmit leg sends;
Sending module, be used for the described transmit leg of described receive direction and return confirmation, the minimum of carrying described recipient in the described confirmation does not receive successful blocks of files information to maximum each blocks of files information and the state indication that receives between the successful blocks of files information.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110100493 CN102170341B (en) | 2009-02-05 | 2009-02-05 | Method and apparatus for data transmission |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110100493 CN102170341B (en) | 2009-02-05 | 2009-02-05 | Method and apparatus for data transmission |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200910008497 Division CN101488840B (en) | 2009-02-05 | 2009-02-05 | Data transmission method and apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102170341A true CN102170341A (en) | 2011-08-31 |
| CN102170341B CN102170341B (en) | 2013-11-06 |
Family
ID=44491331
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201110100493 Active CN102170341B (en) | 2009-02-05 | 2009-02-05 | Method and apparatus for data transmission |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102170341B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015169186A1 (en) * | 2014-05-04 | 2015-11-12 | Tencent Technology (Shenzhen) Company Limited | File transmission method and system |
| CN112019447A (en) * | 2020-08-19 | 2020-12-01 | 博锐尚格科技股份有限公司 | Data flow control method, device, system, electronic equipment and storage medium |
| CN114268416A (en) * | 2021-12-16 | 2022-04-01 | 无锡联云世纪科技股份有限公司 | Data transmission method and device and electronic equipment |
-
2009
- 2009-02-05 CN CN 201110100493 patent/CN102170341B/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015169186A1 (en) * | 2014-05-04 | 2015-11-12 | Tencent Technology (Shenzhen) Company Limited | File transmission method and system |
| CN112019447A (en) * | 2020-08-19 | 2020-12-01 | 博锐尚格科技股份有限公司 | Data flow control method, device, system, electronic equipment and storage medium |
| CN114268416A (en) * | 2021-12-16 | 2022-04-01 | 无锡联云世纪科技股份有限公司 | Data transmission method and device and electronic equipment |
| CN114268416B (en) * | 2021-12-16 | 2023-10-24 | 无锡联云世纪科技股份有限公司 | Data transmission method and device and electronic equipment |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102170341B (en) | 2013-11-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101488840B (en) | Data transmission method and apparatus | |
| US7542438B2 (en) | Reliable multicast data retransmission method by grouping wireless terminals in wireless communication medium and apparatus for the same | |
| CN101945103B (en) | IP (Internet Protocol) network application accelerating system | |
| US8559365B2 (en) | After transmission return signal | |
| EP2119171B1 (en) | Improved data transfer method, system and protocol | |
| US6321269B1 (en) | Optimized performance for transaction-oriented communications using stream-based network protocols | |
| US20150358136A1 (en) | Method and Apparatus For Reducing Feedback and Enhancing Message Dissemination Efficiency in a Multicast Network | |
| CN101933298A (en) | Packet transmission via multiple links in a wireless communication system | |
| CN103905300A (en) | Data message sending method, device and system | |
| US8095116B2 (en) | Method for delivering multimedia files | |
| CN102170341B (en) | Method and apparatus for data transmission | |
| CN110233856B (en) | Message processing method and device and computer readable storage medium | |
| CN105450969A (en) | Real-time video data transmission method and electronic equipment | |
| CN114745273A (en) | TCP acceleration proxy method, device, satellite ground station and readable storage medium | |
| CN107209713A (en) | The method and system that file is repaired on demand | |
| CN101494531A (en) | Method and apparatus for adjusting slide window | |
| CN101764676B (en) | Quality of service securing method and apparatus | |
| CN102065372B (en) | Method for transmitting data in broadcast mode and related device | |
| CN113300818A (en) | Data transmission system and method | |
| CN109729003B (en) | Passenger train time data transmission method and system | |
| CN102802197A (en) | Method and device for transmitting application data | |
| CN113489786B (en) | Reconnection method and retransmission method for weak network of long connection network | |
| CN113517955B (en) | Information transmitting and receiving method, transmitting device and receiving device | |
| CN113612737A (en) | Long message reliable transmission method based on grouping and retransmission mechanism | |
| CN109005011B (en) | Data transmission method and system for underwater acoustic network and readable storage medium |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |