CN105337900A - Segment polymerization based DTN (delay tolerant network) data bundle accelerated transmitting method - Google Patents
Segment polymerization based DTN (delay tolerant network) data bundle accelerated transmitting method Download PDFInfo
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- CN105337900A CN105337900A CN201510810319.5A CN201510810319A CN105337900A CN 105337900 A CN105337900 A CN 105337900A CN 201510810319 A CN201510810319 A CN 201510810319A CN 105337900 A CN105337900 A CN 105337900A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L47/00—Traffic control in data switching networks
- H04L47/10—Flow control; Congestion control
- H04L47/40—Flow control; Congestion control using split connections
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L49/00—Packet switching elements
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- H04L49/9057—Arrangements for supporting packet reassembly or resequencing
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Abstract
The invention discloses a segment polymerization based DTN (delay tolerant network) data bundle accelerated transmitting method. The segment polymerization based DTN (delay tolerant network) data bundle accelerated transmitting method comprises the following steps: forwarding a bundle according to a traditional mode if a middle node receives a complete bundle when a chain II begins; if the middle node only receives partial segment, polymerizing the received segment to serve as load to be packaged in a new bundle for forwarding; and then when the bundle is completely received by the middle node, processing a newly arrived segment in the same manner to be packaged to another bundle to be forwarded, wherein each segment carries an EID(endpoint identifier) of a target node. The method for transmitting the bundle can effectively enhance the use efficiency of a chain, and shorten the time delay introduced by waiting for the receiving of the complete bundle. In addition, the accelerated transmitting method can be used for processing the situation of sudden interruption of the chain in the bundle transmitting process so as to prevent the data transmitting interruption caused by interruption.
Description
Technical field
The present invention relates to technical field of deep space communication, particularly relate to a kind of DTN network data bundle and accelerate transmission method.
Background technology
Space communication has long delay, and link down is frequent, and the features such as high bit-error, make traditional ICP/IP protocol based on end to end connection cannot be applied to the transmission of space exploration data.For overcoming these problems, current space communication extensively adopts the DTN network architecture.DTN provides data transport service by introducing cover layer for potential heterogeneous networks between application layer and transport layer (convergence-level), and its main protocol comprises the LTP agreement of tectal BP agreement and convergence-level.For utilizing the intermittent link connected to guarantee the transmitting of data simultaneously, DTN adopts Store and forword mechanism to carry out forwarded hop-by-hop to data.When carrying out transfer of data, source node application data until (Applicationdataunion, ADU) will be encapsulated in tectal bundle as load.After Bundle transfers to convergence-level, be divided into multiple segment as a LTP block.These segment are sent to intermediate node protocol stack by with the form of isl frame after bottom-layer network process.In this transmitting procedure, the ARQ mechanism of LTP ensure that reliable, the complete reception of bundle.Through once transmitting or repeatedly retransmitting, when receiving complete b undle, intermediate node will utilize (or wait), and down hop link carries out forwarding and sends keeping answer signal to sending node.Deleted from its internal memory by corresponding bundle after sending node receives this signal, the custody of bundle is transferred to receiving node.Through the forwarding of such hop-by-hop, bundle finally will arrive destination node, and the ADU entrained by it will be resumed and consigns to corresponding upper layer application.In this transmitting procedure, due to Store and forword mechanism, intermediate node just can carry out down hop forwarding after only receiving complete bundle.
Carrying out transfer of data to make full use of short chain road, avoiding the waste causing link capacity, DTN defines the bundle burst of two types.
1) active burst (proactivefragmentation)
Active burst was divided into multiple nonoverlapping sub-block before bundle transmission, and each sub-block is transmitted as independently bundle.Burst size is usually according to the time of link expection, and the factors such as memory capacity restriction are chosen.Situation comparatively special in active burst is source burst (sourcefragmentation), the sub-block these sub-blocks being encapsulated in different bundle that load and ADU are divided into non-overlapping copies by source node is transmitted, intermediate node only forwards these bundle, no longer carries out burst to it.When these bundle arrive destination node, the ADU sub-block of wherein carrying is by reorganized.
2) reaction equation burst (reactivefragmentation)
Interrupt in the triggered scenario of the reaction equation burst process that to be link transmit at bundle, cause bundle partial data to be received by intermediate node, the unsuccessful transmission of remaining data.Now, according to the processing method of reaction equation burst, the data (part for load) that part receives will as a sub-block, and the part of unsuccessful transmission will as another sub-block.Be that two sub-blocks add necessary header information as after routing iinformation, blocking information, these sub-blocks will be transmitted as independently bundle, and this bundle of the non-burst simultaneously stored in sending node will be dropped.In the process of bundle transmission of carrying burst, burst again can be carried out to it.
Transmission due to DTN data adopts Store and forword mechanism, and intermediate node only just can carry out the forwarding of down hop under the condition receiving complete b undle, and this character likely causes link utilization insufficient, introduces larger propagation delay time problem.With two-hop link communication for scene illustrates this problem, as shown in Figure 1, T is that link is communicated with the cycle.Consider the defeated impact defeated on the second jump set of the first jump set, point following three kinds of situation discussion.
Sight 1: the first jump set defeated end time is less than Tb2, and intermediate node waits for the connection chance of the second hop link.Now, link II will be fully utilized;
Sight 2: the first jump set defeated end time drops on interval [Tb2, Te1], and it is defeated that intermediate node need wait for that the complete reception of bundle just can carry out the second jump set, causes the junctor of link II beginning to be wasted and can not to be fully used;
Sight 3: the first jump set is defeated to be remained unfulfilled in the Te1 moment, now intermediate node can not carry out the second redirect and sends out (now the second forwarding of jumping need wait for second connection cycle of link) because not receiving complete bundle data, the whole connection chance of link II will be wasted, and introduce larger propagation delay time simultaneously.
Although carry out transfer of data according to two kinds of sliced fashion of bundle can utilize short chain road, avoid the waste causing link capacity, practical application comes with some shortcomings.The burst of active burst determines that the connection rule of the predictability and link depending on link can be expected and knows, connects in the random network occurred at some links, and active burst is difficult to make suitable burst and determines.On the other hand, active burst is chosen less burst according to short chain road and is transmitted, add the required bundle quantity (the bundle header information of required transmission increases) sent, thus introduce larger transport overhead, and active burst occurs before being transmitted, can not tackle the emergency case of link very well.One comparatively effective method adopts reaction equation burst, but reaction equation sliced transmission roughly process is only introduced in current most research, data packet format not in conjunction with agreement provides concrete operations algorithm, and existence hypothesis and bundle head transfer to intermediate node prior to load, when receiving fractional load, intermediate node can utilize the header information received to carry out Route Selection.But consider the existence of channel bit error rate, the reception of data (segment) is random, and this hypothesis may be false.
Summary of the invention
In order to solve the problems of the prior art, the present invention proposes a kind of DTN data bundle based on fragment polymerization and accelerate transmission method, application bundle reaction equation burst, and provide concrete data packet format and transmission and reassembly algorithm, improve the service efficiency of link, reduce and wait for the complete time delay receiving introducing of bundle.
The present invention is achieved through the following technical solutions:
DTN data bundle based on fragment polymerization accelerates a transmission method, it is characterized in that: described method comprises: when link II starts, if intermediate node receives complete bundle, then carries out the second redirect to bundle in the conventional mode and send out; If intermediate node receives only part segment, then collect the segment received, be encapsulated in new bundle as load after being polymerized and carry out the second redirect and send out, then, when the segment of remainder is received completely by intermediate node, newly arrived segment will be encapsulated into after processing in the same way in another bundle and carries out the second redirect and send out; Wherein, described link II is the link that intermediate node arrives destination node, and each segment carries the EID of destination node.
As a further improvement on the present invention, the EID that each segment described carries destination node is specially: the EIDoffset carrying destination node.
As a further improvement on the present invention, described EIDoffset is stored in the Extentions of segment.
As a further improvement on the present invention, dictionary is stored in the internal memory of node.
As a further improvement on the present invention, carry out forwarding be specially being encapsulated in new bundle as load after the segment received is polymerized: Clientservicedata, SessionID, Offset and Length of receiving segment are polymerized to datablock by intermediate node, then it can be used as load to be encapsulated in new bundle and carry out down hop transmission.
As a further improvement on the present invention, the low level of the ProcessingControlFlags of bundle the 6th is utilized to indicate the send mode of bundle.
As a further improvement on the present invention, described 6th is 0 corresponding conventional transmission mode, otherwise for accelerating transmission means.
As a further improvement on the present invention, when destination node receives with the bundle of accelerated mode transmission, to load and the datablock of these bundle be recovered, and the datablock with identical SessionID will be reassembled as LTP block corresponding to original bundle, thus recover ADU.
The invention has the beneficial effects as follows: the bundle that the present invention proposes accelerates transmission mechanism, give the transmission algorithm of concrete data packet format and intermediate node and the reassembly algorithm of destination node, for existing bundle reaction equation burst provides a kind of practicable scheme.By the assessment to acceleration transmission plan performance of the present invention, demonstrate the present invention and accomplish that WTE performance is better than or levels off to the performance of conventional transmission mode compared to the propagation delay time that namely advantage of conventional transmission scheme effectively can reduce bundle simultaneously.So, applying the service efficiency that transmission that acceleration transmission method of the present invention carries out bundle effectively can improve link, reducing the time delay introduced because waiting for complete b undle to receive.In addition, acceleration transmission method of the present invention can be used for handle link happen suddenly in bundle transmitting procedure interrupt situation, avoid because of interrupt cause transfer of data to stop.
Accompanying drawing explanation
Fig. 1 is two-hop link communication scenes schematic diagram;
Fig. 2 (a) is the form schematic diagram of Segment;
Fig. 2 (b) is the file layout schematic diagram of Extensions and EIDoffset;
Fig. 3 is the form schematic diagram of Datablock;
Fig. 4 is the Bundle end-to-end time delay contrast schematic diagram of method of the present invention and conventional method;
Fig. 5 is that method of the present invention and conventional method n consume the impact contrast schematic diagram of WTE to failed transmission, and wherein n represents the segment number that intermediate node receives when link II starts;
Fig. 6 is that method of the present invention and conventional method first jump the impact contrast schematic diagram of segment size on WTE;
Fig. 7 is that method of the present invention and conventional method Bundle head size contrast schematic diagram to the impact of WTE.
Embodiment
In order to make object of the present invention, technical scheme and advantage clearly understand, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, be not intended to limit the present invention.
The present invention for basic research scene with 3 communications shown in accompanying drawing 1, considers the defeated discussion on the defeated impact of the second jump set of the first jump set, designs following send mode:
When link II starts, if intermediate node receives complete bundle, then in the conventional mode the second redirect is carried out to bundle and send out; If intermediate node receives only part segment, then collect the segment received, be encapsulated in new bundle as load after being polymerized and carry out the second redirect and send out; When bundle is received completely by intermediate node, newly arrived segment will be encapsulated into after processing in the same way in another bundle and carries out the second redirect and send out.
Receive the polymerization of segment, transmission and restructuring in order to support sector divides, the present invention makes suitable amendment to bundle/segment form.
The mark (EndpointIdentifier, EID) of DTN network node is stored in the dictionary of bundle, and its position in dictionary is determined by EIDoffset.In these EID, destination node EID plays vital effect to correct route.The segment received for forwarding part must recover dictionary and destination node EIDoffset, thus obtains the EID of destination node.Bundle is divided into multiple segment in convergence-level and transmits, and the dictionary in bundle and destination node EIDoffset may be assigned in multiple segment.Due to channel error probability, the reception of segment is random, so the segment that intermediate node part receives possibly cannot recover dictionary and destination node EIDoffset, thus cannot obtain destination node EID and cannot carry out down hop forwarding.Therefore, for forwarding the random part segment received, each segment should carry destination node EID.
Consider that storing EID can introduce larger transport overhead in segment, the present invention adopts the mode of storage purpose node EIDoffset.Reduce protocol overhead for storing EIDoffset in segment, destination node EIDoffset is stored in the Extentions in segment by the present invention simultaneously.Extensions is for expanding the function of basic LTPsegment, and as shown in Figure 3, wherein " ext-tag " is for indicating this expanded function for its position in segment and form.The file layout of destination node EIDoffset in Extensions as accompanying drawing 2 (b) mark and with 0xC0 indicate this expanded function (" ext-tag " span is 0x00-0xFF, wherein 0xC0-0xFF be agreement retain experiment field).
Because EIDoffset needs dictionary for inquiry, but consider that dictionary length is comparatively large, it is unpractiaca for being stored in segment.Therefore, dictionary is stored in node memory by the present invention.Compared to ground network, the number of nodes of space DTN is less, and therefore the method can not take node memory in a large number.If adopt suitable naming method to reduce its length to EID, the node memory shared by dictionary can be reduced further.
Consider that intermediate node cannot recover complete ADU when receiving part segment, so traditional mode cannot be adopted to forward ADU to next node.For addressing this problem, the method that the present invention adopts segment to be polymerized, prioritised transmission Clientservicedata.Concrete grammar is that Clientservicedata, SessionID, Offset and Length of receiving segment are polymerized to datablock by intermediate node, then it can be used as load to be encapsulated in new bundle and carries out down hop transmission.As shown in Figure 3, SessionID belongs to the datablock of same session to the form of Datablock for indicating, and Offset and Length indicates the position of Clientservicedata relative to original LTP block by being used for.
Because intermediate node can adopt conventional transmission mode according to the reception condition of bundle or accelerate transmission means, destination node should be able to identify the bundle sent with different send mode, thus takes respective handling method to recover ADU.For this reason, the present invention utilizes the low level of the ProcessingControlFlags of bundle the 6th (agreement reserved place) to indicate the send mode of bundle, if this position is 0, and corresponding conventional transmission mode, otherwise for accelerating transmission means.When destination node receives with the bundle of accelerated mode transmission, load and the datablock of these bundle will be recovered, and the datablock with identical SessionID is reassembled as LTP block corresponding to the first jumping bundle (original bundle), thus recover ADU.In this regrouping process, the position rearrangement that the Clientservicedata with " Length " length will indicate by its Offset.
According to the above amendment to bundle/segment form and in conjunction with send mode, concrete transmission and reassembly algorithm are respectively as shown in Table 1 and Table 2.
The transmission algorithm of table 1 acceleration transmission method of the present invention
The reassembly algorithm of table 2 acceleration transmission method of the present invention
For verifying the advantage of acceleration transmission method of the present invention, the present invention is with bundle end-to-end time delay and failed transmission consumption (Wastedtransmissioneffort, WTE) be performance index, in conventional transmission mode for comparison other, carry out Performance Evaluation to transmission method of the present invention, experimental result as illustrated in figs. 4-7.
Accompanying drawing 4 compared for the bundle end-to-end time delay of method of the present invention and conventional transmission mode.From accompanying drawing 4, method of the present invention effectively reduces the propagation delay time of bundle.When segment sum N is less than 26, the transmission time increases along with the increase of N; When N is greater than 26, situation is contrary.The reason of this phenomenon be when bundle size is certain segment number N comparatively large then segment size is less, thus the packet loss of correspondence is less, makes more segment arrive intermediate node and acceleratedly transfer to destination node.On the other hand, when segment number is less, the header overhead of required transmission is less, and the transmission time also can correspondingly reduce.
Accompanying drawing 5-7 have studied the impact of key parameter on the WTE of method of the present invention.From accompanying drawing 5 simultaneously 6 (wherein n represents the segment number that intermediate node receives when link II starts) by reference to the accompanying drawings, less by (10 in the error rate
-6) when method of the present invention performance be better than conventional transmission mode; In the error rate comparatively large (10
-5) when, for reaching the object being better than conventional transmission scheme performance, the defeated segment of the first jump set should select then less size, otherwise needs to ask to receive more segment at intermediate node.The impact of size on method performance of the present invention that accompanying drawing 7 shows bundle head is less.Due to the method adopting dictionary to be stored in internal memory, bundle head size can not occur significantly to change, so almost can ignore the impact of bundle head size change on method performance of the present invention.
Above content is in conjunction with concrete preferred implementation further description made for the present invention, can not assert that specific embodiment of the invention is confined to these explanations.For general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, some simple deduction or replace can also be made, all should be considered as belonging to protection scope of the present invention.
Claims (8)
1. the DTN data bundle based on fragment polymerization accelerates a transmission method, it is characterized in that: described method comprises: when link II starts, if intermediate node receives complete data bundle bundle, then forwards bundle in the conventional mode; If intermediate node receives only part segment, then collect the segment received, be encapsulated in new bundle as load after being polymerized and forward, then, when the segment of remainder is received completely by intermediate node, newly arrived segment will be encapsulated in another bundle after processing in the same way and forwards; Wherein, described link II is the link that intermediate node arrives destination node, and each segment carries the EID of destination node.
2. data bundle according to claim 1 accelerates transmission method, it is characterized in that: the EID that each segment described carries destination node is specially: the EIDoffset carrying destination node.
3. data bundle according to claim 2 accelerates transmission method, it is characterized in that: described EIDoffset is stored in the Extentions of segment.
4. data bundle according to claim 2 accelerates transmission method, it is characterized in that: internal memory dictionary being stored in node.
5. data bundle according to claim 1 accelerates transmission method, it is characterized in that: carry out forwarding be specially being encapsulated in new bundle as load after the segment received is polymerized: Clientservicedata, SessionID, Offset and Length of receiving segment are polymerized to datablock by intermediate node, then it can be used as load to be encapsulated in new bundle and carry out down hop transmission.
6. data bundle according to claim 1 accelerates transmission method, it is characterized in that: utilize the low level of the ProcessingControlFlags of bundle the 6th to indicate the send mode of bundle.
7. data bundle according to claim 6 accelerates transmission method, it is characterized in that: described 6th is 0 corresponding conventional transmission mode, otherwise for accelerating transmission means.
8. data bundle according to claim 1 accelerates transmission method, it is characterized in that: when destination node receives with the bundle of accelerated mode transmission, load and the datablock of these bundle will be recovered, and the datablock with identical SessionID is reassembled as LTP block corresponding to original bundle, thus recover ADU.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103095438A (en) * | 2013-01-09 | 2013-05-08 | 哈尔滨工业大学深圳研究生院 | Deep space delay tolerant network (DTN) multiple hop transmission method |
| CN105049152A (en) * | 2015-08-10 | 2015-11-11 | 哈尔滨工业大学深圳研究生院 | Space-error-channel-oriented DTN data aggregation transmission method |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103095438A (en) * | 2013-01-09 | 2013-05-08 | 哈尔滨工业大学深圳研究生院 | Deep space delay tolerant network (DTN) multiple hop transmission method |
| CN105049152A (en) * | 2015-08-10 | 2015-11-11 | 哈尔滨工业大学深圳研究生院 | Space-error-channel-oriented DTN data aggregation transmission method |
Non-Patent Citations (4)
| Title |
|---|
| LOREN CLARE,ET.AL: "《Endpoint Naming for Space Delay / Disruption Tolerant Networking》", 《IEEE》 * |
| MARTIN WEGNER,ET.AL: "《Bundle Protocol Header Compression》", 《ACM》 * |
| NIKOLAOS BEZIRGIANNIDIS,ET.AL: "《TR-Delivery Time Estimation for Space Bundles》", 《IEEE》 * |
| 袁鹏: "《基于BP_LTP的空间DTN传输策略优化研究》", 《万方数据企业知识服务平台》 * |
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