CN107071015A - A kind of document transmission method and device applied to vehicular ad hoc network - Google Patents
A kind of document transmission method and device applied to vehicular ad hoc network Download PDFInfo
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- CN107071015A CN107071015A CN201710203629.XA CN201710203629A CN107071015A CN 107071015 A CN107071015 A CN 107071015A CN 201710203629 A CN201710203629 A CN 201710203629A CN 107071015 A CN107071015 A CN 107071015A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L67/00—Network arrangements or protocols for supporting network services or applications
- H04L67/01—Protocols
- H04L67/12—Protocols specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
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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
- H04L47/12—Avoiding congestion; Recovering from congestion
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L67/00—Network arrangements or protocols for supporting network services or applications
- H04L67/01—Protocols
- H04L67/06—Protocols specially adapted for file transfer, e.g. file transfer protocol [FTP]
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- Computer Networks & Wireless Communication (AREA)
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- General Health & Medical Sciences (AREA)
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Abstract
The invention discloses a kind of document transmission method and device applied to vehicular ad hoc network, this method includes：NDN mechanism is incorporated into vehicle-mounted net, requestor sends interest bag to turning originator；Turn originator and judge whether the numerical value of respective file fragment data bag in the interest bag is equal to 1；If the numerical value of file fragment packet is not equal to 1, turns originator and inquire about file fragment packet whether is cached with itself CS；If turning originator is cached with least one described file fragment packet, then turn originator newly-built list item in the interest table undetermined to be used for recording the interest bag, and the numerical value of the corresponding file fragment packet of interest bag is assigned to the fragments counter of the list item, and at least one file fragment packet is sent to requestor successively, and a packet is often sent, the numerical value of the fragments counter subtracts 1.This method can reduce the number of times of forward node forwarding, so as to avoid vehicle flowrate from being possible to the network congestion brought when increasing.
Description
Technical field
The present invention relates to communication technical field, more particularly to a kind of document transmission method and dress applied to vehicular ad hoc network
Put.
Background technology
Vehicular ad hoc network (Vehicle ad hoc networks, VANET) refers in traffic environment between vehicle, car
Between fixed access point and point-to-point (Ad hoc) network of open type moving that vehicle and the intercommunication of pedestrian are constituted.
VANET target is to build self assembly on road, dispose between convenient, low-cost, structure opening vehicle
Communication network；And non-stop layer, self-organizing, the file transfer capability for supporting multi-hop transmission are provided, to realize that accident early warning, auxiliary are driven
Sail, Traffic Information inquiry, the application such as inter-vehicle communication and Internet access service.
At present, name data network (Named Date Networks, NDN) is introduced into vehicular ad hoc network and constitutes V-NDN
Network, to improve the efficiency of network transmission.NDN networks are a kind of brand-new network systems centered on content and information.NDN
Web vector graphic data name rather than IP address carry out data forwarding, allow data to turn into key element in the Internet architecture in itself.
Therefore, the problem of IP address is distributed in traditional IP can be solved by NDN mechanism being combined with VANET；And NDN networks is slow
The mechanism of depositing can allow resource request node to obtain data in the node nearest apart from it, and then avoid because server info is concentrated
And there is the generation of servers go down or network congestion.
However, in NDN networks, for the larger file of some Capacity Ratios, it is necessary to by file fragmentation, then to each
Section sends interest bag (Internet Packet) and made requests on respectively, now to broadcasting the car of interest bag by flooding mechanism
Contained network brings some detrimental effects.For example：The file of request, which is divided into around 10 fragments, each node, 5 neighbours' sections
Point；Need to send 10 interest bags, 5 intermediate nodes of surrounding, which are received, is again turned these interest bags in the form of broadcast after interest bag
Issue nodes all around；Then, these nodes are broadcasted after receiving the interest bag.Interest bag during transmission,
The interest bag quantity of forwarding is increased in multiple, therefore this method causes interest bag quantity to increase sharply, and undoubtedly adds network and opens
Pin, wastes network traffics, it is also possible to can cause the conflict of packet in network.
That is, how to reduce the number of times of forward node forwarding, and then reduce the quantity of interest bag in network, it is to avoid car
The network congestion brought is possible to when flow increases, as urgent problem to be solved.
The content of the invention
Weak point present in regarding to the issue above, the application provides a kind of file applied to vehicular ad hoc network and transmitted
Method and device, this method can reduce the number of times of forward node forwarding, and then reduce the quantity of interest bag in network, so as to keep away
Exempt from the network congestion for being possible to bring when vehicle flowrate increases.
The application first aspect provides a kind of document transmission method applied to vehicular ad hoc network, and methods described includes：
The requestor sends interest bag to turning originator；Wherein, the interest bag includes the title and request text of demand file
The numerical value of the corresponding file fragment packet of part, it is described to turn structure C S of the originator including interest table undetermined and data cached bag；Institute
State turn originator judge respective file fragment data bag in the interest bag numerical value whether be equal to 1；If the file fragment data
The numerical value of bag is not equal to 1, described to turn originator and inquire about in itself CS whether be cached with the file fragment packet；If the forwarding
Person is cached with least one described file fragment packet, then described to turn originator newly-built list item in the interest table undetermined
For recording the interest bag, and the numerical value of the corresponding file fragment packet of the interest bag is assigned to the fragment of the list item
Counter, and at least one described file fragment packet is sent to the requestor, and often one packet of transmission successively,
The numerical value of the fragments counter subtracts 1；Turn the uncached file fragment packet in originator CS if described, it is described to turn originator
Inquire about the record that the interest bag whether is preserved in the interest table undetermined；When not preserving described emerging in the interest table undetermined
During the record of interest bag, the originator that turns sets up the list item of the interest bag in the interest table undetermined, and forwards the interest
Bag.
In a kind of possible implementation, methods described also includes：When preserving described emerging in the interest table undetermined
During the record of interest bag, the originator that turns increases a port described in the interest table undetermined in the interface list of interest bag
Number；After the fragments counter numerical value for turning originator in the interest table undetermined subtracts 1, in addition to：If the interest table undetermined
In fragments counter be 0, then it is described to turn the record that originator deletes the interest bag in the interest table undetermined.
In a kind of possible implementation, methods described also includes：The producer sends at least one packet to described
Turn originator, the packet is the file fragment packet that the interest bag is asked；The originator that turns judges whether itself caches
There is the packet；If described turn the uncached packet of originator, the originator that turns is inquired about in the interest table undetermined
Whether the record of the packet corresponding interest bag is preserved；If preserving the packet correspondence in the interest table undetermined
Interest bag record, then the originator that turns the packet is transmitted to the requestor, while by the pair of the packet
Originally it is buffered in local CS, and often sends a packet, the fragments counter numerical value in the interest table undetermined subtracts 1.
It is described to turn originator judges itself whether be cached with the packet in a kind of possible implementation, in addition to：
If the originator that turns preserves the packet, the originator that turns abandons the packet；The originator that turns is described undetermined
The record for whether having the corresponding interest bag of the packet is inquired about in interest table, in addition to：If not protected in the interest table undetermined
The record of the corresponding interest bag of the packet is deposited, then the originator that turns caches the packet；The originator that turns is treated described
After fragments counter numerical value in the interest table of Dingxing subtracts 1, in addition to：If the fragments counter in the interest table undetermined is 0, institute
State and turn the record that originator deletes the corresponding interest bag of the packet in the interest table undetermined.
In a kind of possible implementation, the interest table undetermined include the interest bag in demand file title,
The receiving port number and the fragments counter of the interest bag；Wherein, the fragments counter is used to count the interest
The number for the file fragment packet that bag correspondence is not yet asked；The title of the demand file includes protocol name, city
The sequence number of name, metropolitan district domain name, request content and request content fragment；And at least one institute of interest bag correspondence
State file fragment packet.
The application second aspect provides a kind of file transfer means applied to vehicular ad hoc network, and described device is forwarding
Person, the originator that turns includes communication unit and processing unit；The communication unit, sends interest bag to turning originator；Wherein, it is described
Interest bag includes the title of demand file and the numerical value of the corresponding file fragment packet of the demand file, described to turn originator
Structure C S including interest table undetermined and data cached bag；The processing unit, judges respective file fragment in the interest bag
Whether the numerical value of packet is equal to 1；If the numerical value of the file fragment packet is not equal to 1, the originator that turns inquires about itself CS
In whether be cached with the file fragment packet；If the originator that turns is cached with least one described file fragment packet,
Then the originator newly-built list item in the interest table undetermined that turns is used for recording the interest bag, and by the interest bag pair
The numerical value for the file fragment packet answered is assigned to the fragments counter of the list item, and by least one file fragment data
Bag is sent to the requestor successively, and often sends a packet, and the numerical value of the fragments counter subtracts 1；If the forwarding
The uncached file fragment packet in person CS, then it is described to turn whether preserve described in the originator inquiry interest table undetermined
The record of interest bag；When not preserving the record of the interest bag in the interest table undetermined, the originator that turns is described undetermined
The list item of the interest bag is set up in interest table, and forwards the interest bag.
In a kind of possible implementation, the processing unit is additionally operable to preserve in the interest table undetermined
When stating the record of interest bag, the originator that turns increases an end described in the interest table undetermined in the interface list of interest bag
Slogan；After the fragments counter numerical value for turning originator in the interest table undetermined subtracts 1, in addition to：If the interest undetermined
Fragments counter in table is 0, then described to turn the record that originator deletes the interest bag in the interest table undetermined.
In a kind of possible implementation, the communication unit receives at least one packet that the producer sends, institute
It is the file fragment packet that the interest bag is asked to state packet；The processing unit, judges whether be cached with itself CS
The packet；Turn the uncached packet of originator if described, it is described turn originator and inquired about in the interest table undetermined be
The no record for preserving the corresponding interest bag of the packet；If it is corresponding to preserve the packet in the interest table undetermined
The record of interest bag, then the originator that turns the packet is transmitted to the requestor, while by the copy of the packet
It is buffered in local CS, and often sends a packet, the fragments counter numerical value in the interest table undetermined subtracts 1.
In a kind of possible implementation, the processing unit judges whether itself is cached with the packet, also wraps
Include：If the originator that turns preserves the packet, the originator that turns abandons the packet；The originator that turns is treated described
The record for whether having the corresponding interest bag of the packet is inquired about in the interest table of Dingxing, in addition to：If in the interest table undetermined not
The record of the corresponding interest bag of the packet is preserved, then the originator that turns caches the packet；The originator that turns is described
After fragments counter numerical value in interest table undetermined subtracts 1, in addition to：If the fragments counter in the interest table undetermined is 0,
It is described to turn the record that originator deletes the corresponding interest bag of the packet in the interest table undetermined.
In a kind of possible implementation, the interest table undetermined include the interest bag in demand file title,
The receiving port number and the fragments counter of the interest bag；Wherein, the fragments counter is used to count the interest
The number for the file fragment packet that bag correspondence is not yet asked；The title of the demand file includes protocol name, city
The sequence number of name, metropolitan district domain name, request content and request content fragment；And at least one institute of interest bag correspondence
State file fragment packet.
The application can reduce the number of times of forward node forwarding, and then reduce the quantity of interest bag in network, so as to avoid
The network congestion brought is possible to when vehicle flowrate increases.
Brief description of the drawings
Fig. 1 is a kind of numerical nomenclature network N DN network architecture schematic diagram provided in an embodiment of the present invention；
Fig. 2 is a kind of document transmission method schematic flow sheet applied to vehicular ad hoc network provided in an embodiment of the present invention；
Fig. 3 illustrates for another document transmission method flow for being applied to vehicular ad hoc network provided in an embodiment of the present invention
Figure；
Fig. 4 is a kind of file transfer means structural representation applied to vehicular ad hoc network provided in an embodiment of the present invention；
Fig. 5 is the contrast schematic diagram of the interest bag quantity reduction of transmission method in the embodiment of the present invention；
Fig. 6 is the contrast schematic diagram of the hop count reduction of transmission method in the embodiment of the present invention；
Fig. 7 is the contrast schematic diagram of the network overhead reduction of transmission method in the embodiment of the present invention.
Embodiment
To make the purpose, technical scheme and advantage of the embodiment of the present invention clearer, below in conjunction with the embodiment of the present invention
In accompanying drawing, the technical scheme in the embodiment of the present invention is clearly and completely described, it is clear that described embodiment is
A part of embodiment of the present invention, rather than whole embodiments.Based on the embodiment in the present invention, ordinary skill people
The every other embodiment that member is obtained on the premise of creative work is not made, belongs to the scope of protection of the invention.
In the embodiment of the present invention, requestor or to turn originator or the producer be the terminal device with communication function, the terminal
Equipment can communicate each other, including the equipment such as mobile phone, tablet personal computer, car-mounted device；In the embodiment of the present invention requestor or
Turn originator or the producer all to illustrate by taking the car-mounted device with communication function as an example.
In NDN networks, the file of transmission is broadly divided into two classes according to amount of capacity, and a class is that some information content are very small
Message, such as：Some real-time messages or some announcement informations, these contents are fewer, can put them on a packet
In by once ask obtain.Now, the transmission of information is carried out according to standard NDN forwarding processes, and information requester is sent
Interest bag (Interest Packet), then the message producer information is put into return in a packet (Date Packet)
To requestor.Another kind of is exactly the larger file of Capacity Ratio, such as music and video, because the information content entrained by each packet
It is limited, these files can not possibly all be put into a packet and return to requestor；Now, Normal practice is by file
It is divided into multiple fragments, segment requests；These fragments are merged into a complete file again after request is to all fragments.Cause
This, may when in the vehicle-mounted net communicated by radio broadcasting can produce vehicle flowrate as mentioned in the background art and increasing
The problem of network congestion brought.
Fig. 1 is a kind of numerical nomenclature network N DN network architecture schematic diagram provided in an embodiment of the present invention, as described in Figure 1,
Requestor 1 sends interest bag to originator 2 is turned, and turns originator 2 and interest bag is sent into the producer 3；The producer 3 is corresponding by interest bag
Packet, which is sent to, turns originator 2, turns originator 2 and the packet is transmitted into requestor 1.
It should be noted that in vehicular ad hoc network VANET, all car-mounted devices are likely to be requestor, also may be used
Can turn originator, it is also possible to the producer.
In addition, the node in each NDN network, all includes the content storage of the structure of data cached bag, i.e. node
(Content Storage, CS)；Also include interest table undetermined (Pending interest package, PIT).
In the embodiment of the present invention, the one or more fragment datas of interest bag (Persistent Interest) correspondence.
The file of request is divided into after multiple fragments by requestor, and an interest bag can be with permanently effective；Even if having obtained the interest bag
Corresponding packet, is also removed not from interest table (PIT) undetermined.The interest bag can exist in PIT always, therefore requestor passes through
Sending a small amount of interest bag just can obtain substantial amounts of packet, and turning originator or the producer can be sent to according to the port numbers of request
Requestor.
Under vehicle-mounted net environment, the purpose of NDN document transmission methods to the greatest extent may be used on the premise of complete file is arrived in request
The transmission of the reduction interest bag of energy.Need to consider problems with：
First, in NDN network nodes data structure change.Such as：One file of requester requests can be divided into 10
Fragment, and the forward node between requestor and the producer does not know that the request needs how many packets of forwarding to constitute
Complete file.If turning the number that originator does not know fragment in file, then it is possible to before all packets are received
The record in PIT tables to being deleted, cause requester requests to file be incomplete.Therefore, interest bag or packet
During transmission, it is necessary to the number of fragments information transmission contained by file give along road it is all turn originator, allow and turn originator according to transmission
The information come carrys out the reception and forwarding of process content bag.In NDN forwarding mechanisms, requestor, the producer and to turn originator be exactly logical
Cross interest bag and packet is communicated, therefore file fragment information can be embedded into interest bag and packet, transmitted
To turning originator.In addition, a field should be also added in the corresponding list items of PIT to be used for storing this document information.
Furthermore, it is necessary to take into account the problem of be exactly PIT list items record life span.I.e. when a forward node receives one
After interest bag, by interest bag record in PIT tables, and one life span is set for the record.If in the forward node
Before receiving the packet for returning and, life span time-out, then PIT tables will be automatically the record deletion, then consumer
Retransmit interest bag.But in the embodiment of the present invention, it is desirable to it is that an interest bag can match multiple fragments, it is a kind of
Can be with long-standing interest bag.Therefore need to solve the problems, such as to set emerging in record of interest life span in PIT, the embodiment of the present invention
Interesting bag life span is constant, and whether the data packet number for being judged as receiving whenever a packet is received is equal to request fragments
Quantity；If equal to, just by the record deletion in PIT tables；If it is not, so timer is reset, reclocking；When receiving again
Judged again to during packet, then reclocking.
That is, in the embodiment of the present invention, during requestor passes to the number of fragments of demand file by interest bag
Between forward node, then again by the information set into the PIT tables of node；When turning originator forwarding, when receiving a packet,
Request fragments quantitative value corresponding to the corresponding list items of PIT is subtracted 1；When the request fragments quantity reduces to 0, illustrate requester requests
All fragments all obtain, can be by this record deletion in PIT tables.
And then, NDN networks be network using content as center, so in NDN networks content storage, search and turn
Hair is all based on the title of content.The structure of therefore named title can produce considerable influence to availability and autgmentability, in order to realize name number
Reliably obtained according in the whole network, name structure is designed.
In the embodiment of the present invention, file fragment packet name structure uses hierarchical structure.The name of data is divided into not
Same several parts, the length of each part is not fixed.
As shown in table 1, the name structure of file fragment packet includes this several part：Protocol name (protocol name),
City (city), region (area) and request content (requseted data).Request content is divided into two parts, i.e. content again
The sequence number (seg no.) of name (data name) and the contents fragment.
Part I protocol name represents the data application, in what network, what agreement, the embodiment of the present invention is used
Defined in be V-NDN；Part II is the city where the data；Part III is the specific region where the data；4th
Part is the name of request data.Because the music file asked in the vehicular ad hoc network may need to divide than larger
Fragment, here the name of data be divided into data name and fragment sequence number again.For example, music file name can be with as follows：/V-
NDN/beijing/chaoyang/ Carmdlo Anthonies .MP3/seg2.
In data slot field (seg no.) in numerical nomenclature structure, if request is multiple packets, the word
Section is set to sky；If single packet, then the fragment name of request data package is set to.
In the embodiment of the present invention, increase a field in interest bag to store the number of demand file fragment.Exist simultaneously
Also corresponding setting is done in PIT tables.The structure that interest includes, it is as shown in table 1 below：
| File fragment package name (Name) |
| Options (Selectors) |
| Options (Guiders) |
| Random number (Nonce) |
| Fragments counter (RequestDateNumb) |
Table 1
As shown in table 1, increase a counter field (RequestDataNumb) and come what statistical content requestor was asked
Data include the packet number of fragment.Interest bag is the request bag that data requester is sent, and includes the name of requested data
Word (Name)；And some subsidiary selective information (Selectors), including priority sequence, publisher's filter, range of transmission
And interest bag life cycle etc.；Random number N once, when a forward node connects interest bag, if detect two it is of the same name
And Nonce identical interest bags just represent receive be repeat request, then node will give up this interest bag.Increase
After the field, the segments value that demand file is included will be passed to by interest bag turns originator, then turn originator just
The forwarding of interest bag and the processing of content bag can be controlled by the value.
In the embodiment of the present invention, the structure of PIT tables is as shown in table 2：
| File fragment package name | Fragment computations device | Receiving port number |
| / v-NDN/beijing/chaoyang/ Carmdlo Anthonies .mp3/ | 5 | 0 |
| / v-NDN/beijing/chaoyang/ fireworks easily cold .mp3/ | 6 | 1 |
Table 2
As shown in table 2, PIT tables are forwarded over for depositing the forward node, but not yet get respective numbers number
According to the interest package informatin of bag, the data name (Name) and receiving port number (face) of interest bag are contained.Increase in PIT tables
One field (Segment Count) is used for counting the number for the packet (fragment) being not yet met in some interest bag,
Initial value is the value of the interest bag Counter received, if the counter is zero, has illustrated the data of interest bag request
All obtain.
The transfer process to the embodiment of the present invention is illustrated below.Fig. 2 is a kind of application provided in an embodiment of the present invention
In the document transmission method schematic flow sheet of vehicular ad hoc network, as shown in Fig. 2 the method comprising the steps of S201-S206.
S201, the requestor sends interest bag to turning originator；Wherein, the interest bag includes the title of demand file
The numerical value of file fragment packet corresponding with the demand file, the originator that turns includes interest table undetermined and data cached bag
Structure C S.
In the step, the structure of data cached bag stores CS for content, for storage file fragment data bag.
S202, the originator that turns judges whether the numerical value of respective file fragment data bag in the interest bag is equal to 1.
Now, if turning originator judges that the numerical value of the interest bag homologous segment is equal to 1, that is, represent that requestor simply requests one
Packet, is then conventionally forwarded；The embodiment of the present invention is in this regard, without describing in detail.
S203, it is described to turn originator and inquire about in itself CS whether to cache if the numerical value of the file fragment packet is not equal to 1
There is the file fragment packet.
In this step, turn originator inquires about itself whether preserve the interest bag correspondence in the content storage CS of itself
Fragment data；Be stored with the titles of one or more file fragment packets in the CS, and file fragment packet.
S204, if the originator that turns is cached with least one described file fragment packet, the originator that turns is described
A newly-built list item is used for recording the interest bag in interest table undetermined, and by the corresponding file fragment packet of the interest bag
Numerical value be assigned to the fragments counter of the list item, and by least one described file fragment packet be sent to successively it is described please
The person of asking, and a packet is often sent, the numerical value of the fragments counter subtracts 1.
Now, after the fragments counter numerical value for turning originator in the sub-domains display subtracts 1, if the interest undetermined
Fragments counter in table is 0, then the originator that turns deletes the corresponding interest bag of the packet in the interest table undetermined
Record.
S205, the uncached file fragment packet of originator is turned if described, described to turn to treat Dingxing described in originator inquiry
Whether the record of the interest bag is preserved in interesting table.
S206, when not preserving the record of the interest bag in the interest table undetermined, the originator that turns is described undetermined
The list item of the interest bag is set up in interest table, and forwards the interest bag.
In addition, when preserving the record of the interest bag in the interest table undetermined, the originator that turns is described undetermined
Increase a port number described in interest table in the interface list of interest bag.Pass through not that is, there are different requestors
With port numbers, carry out demand file to turning originator and send identical interest bag；Therefore, a port number is increased here, to distinguish
Different requestors.
The above-mentioned transfer process for interest bag, below by taking Fig. 3 as an example, the transfer process to packet is illustrated.Fig. 3 is
It is provided in an embodiment of the present invention another be applied to vehicular ad hoc network document transmission method schematic flow sheet.
As shown in figure 3, the method comprising the steps of S301-S204.
S301, the producer sends at least one packet and turns originator to described, and the packet is asked for the interest bag
File fragment packet.
S302, the originator that turns judges the packet whether is cached with itself CS.
In the step, if the originator that turns preserves the packet, the originator that turns abandons the packet.
S303, if described turn the uncached packet of originator, the originator that turns is inquired about in the interest table undetermined
Whether the record of the packet corresponding interest bag is preserved.
In this step, if not preserving the record of the corresponding interest bag of the packet, institute in the interest table undetermined
State and turn the originator caching packet.
S304, if preserving the record of the corresponding interest bag of the packet, the forwarding in the interest table undetermined
The packet is transmitted to the requestor by person, while the copy of the packet is buffered in local CS, and is often sent
One packet, the fragments counter numerical value in the interest table undetermined subtracts 1.
Turn originator packet one copy of making is buffered in local CS, here it is the caching mechanism of NDN networks；This
When, the producer that originator can serve as information that turns of the packet has been cached, has been that other requestors service, this is NDN nets
A critically important mechanism in network, is also its advantage place for the existing TCP/IP networks of contrast.
Now, after the fragments counter numerical value for turning originator in the PIT subtracts 1, if in the interest table undetermined
Fragments counter is 0, then described to turn the record that originator deletes the corresponding interest bag of the packet in the interest table undetermined.
In one example, the interest table undetermined includes the title of demand file, the interest bag in the interest bag
Receiving port number and the fragments counter.The fragments counter is arrived for counting the interest bag correspondence not yet request
The file fragment packet number；The title of the demand file include protocol name, city name, metropolitan district domain name, please
Seek the sequence number of content and request content fragment.
In one example, at least one corresponding described fragment data of an interest bag.
Fig. 4 is a kind of file transfer means structural representation applied to vehicular ad hoc network provided in an embodiment of the present invention.
As shown in figure 4, described device is turns originator 400, it is described to turn originator 400 including communication unit 401 and processing unit 402 and deposit
Storage unit 403.Memory cell 403 stores computer instruction, in order to the computer instructions of processing unit 402, communication unit
401 are communicated with external equipment.
The communication unit 401, sends interest bag to turning originator；Wherein, the interest bag includes the name of demand file
Claim the numerical value of file fragment packet corresponding with the demand file, the originator that turns includes interest table undetermined and data cached
The structure of bag；
The processing unit 402, judges whether the numerical value of respective file fragment data bag in the interest bag is equal to 1；
If the numerical value of the file fragment packet is not equal to 1, the originator that turns inquires about whether itself is cached with the text
Part fragment data bag；
If the originator that turns is cached with least one described file fragment packet, the originator that turns treats Dingxing described
A newly-built list item is used for recording the interest bag in interesting table, and by the numerical value of the corresponding file fragment packet of the interest bag
The fragments counter of the list item is assigned to, and at least one described file fragment packet is sent to the requestor successively,
And a packet is often sent, the numerical value of the fragments counter subtracts 1；
If described turn the uncached file fragment packet of originator, the originator that turns is inquired about in the interest table undetermined
Whether the record of the interest bag is preserved；
When not preserving the record of the interest bag in the interest table undetermined, the originator that turns is in the interest table undetermined
It is middle to set up the list item of the interest bag, and forward the interest bag.
In said apparatus, the processing unit 402 is additionally operable to work as in the interest table undetermined and preserves the interest bag
Record when, it is described turn originator described in the interest table undetermined in the record of interest bag increase a port number；Described turn
After fragments counter numerical value of the originator in the interest table undetermined subtracts 1, in addition to：If the fragment meter in the interest table undetermined
Number device is 0, then described to turn the record that originator deletes the interest bag in the interest table undetermined.
In said apparatus, the communication unit 401 receives at least one packet that the producer sends, the data
Wrap the file fragment packet asked for the interest bag；The processing unit 402, judges whether itself is cached with the data
Bag；Turn the uncached packet of originator if described, it is described to turn originator and inquire about in the interest table undetermined whether to preserve
The record of the corresponding interest bag of the packet；If preserving the corresponding interest bag of the packet in the interest table undetermined
Record, then the packet is transmitted to the requestor by the originator that turns, while the copy of the packet is buffered in into this
In ground CS, and a packet is often sent, the fragments counter numerical value in the interest table undetermined subtracts 1.
In said apparatus, the processing unit 402 judges itself whether be cached with the packet, in addition to：If institute
State and turn originator and preserve at least one described packet, then the originator that turns abandons the packet；The originator that turns is described
The record for whether having the corresponding interest bag of the packet is inquired about in interest table undetermined, in addition to：If in the interest table undetermined
The record of the corresponding interest bag of the packet is not preserved, then the originator that turns preserves the packet；The originator that turns is in institute
State after the fragments counter numerical value in interest table undetermined subtracts 1, in addition to：If the fragments counter in the interest table undetermined is 0,
It is then described to turn the record that originator deletes the corresponding interest bag of the packet in the interest table undetermined.
In said apparatus, the interest table undetermined includes the title of demand file, the interest bag in the interest bag
Receiving port number and the fragments counter；Wherein, the fragments counter is used to count the interest bag correspondence not yet
The number for the file fragment packet asked；The title of the demand file includes protocol name, city name, urban area
The sequence number of name, request content and request content fragment；And at least one corresponding described file fragment of an interest bag
Packet.
Unaccomplished matter in the embodiment of the present invention, refers to shown in Fig. 2, Fig. 3 and above-mentioned word segment, will not be repeated here.
The effect that the present invention is implemented is illustrated with reference to experimental data.The data qualification of experiment is as shown in table 3,
Table 3
The quantity of the main interest bag in a network of the embodiment of the present invention, the hop count and network overhead of NDN network nodes
These three aspects are estimated to the transmission method of the application, the conventional retransmission method before contrasting as improvement.Such as Fig. 5, Fig. 6, Fig. 7
In, L1 represents the document transmission method of the application；L2 represents the conventional retransmission method of NDN networks.
Fig. 5 is the contrast schematic diagram of the interest bag quantity reduction of transmission method in the embodiment of the present invention.What Fig. 5 was represented is certain
Interest bag quantity sum in individual moment network, and be the interest bag sum of all nodes in network.As shown in Figure 5, at some
Carve, requestor is on the premise of the resource file of identical quantity is asked, and L1 interest bag quantity of the interest bag quantity more than L2 is few,
The reduction of interest bag quantity helps to reduce network traffics, saves expense.
Fig. 6 is the contrast schematic diagram of the hop count reduction of transmission method in the embodiment of the present invention.What Fig. 6 was represented is some
Moment nodes forward interest bag number of times sum, and Fig. 6 is understood, sometime, requestor is asking identical quantity resource
On the premise of file, L1 target node number of times of the target node number of times more than L2 is few.The reduction of forwarding algorithm has
Help reduce network burden, improve network performance.
Fig. 7 is the contrast schematic diagram of the network overhead reduction of transmission method in the embodiment of the present invention.What Fig. 7 was represented is each
Moment network overhead, as shown in Figure 7 at each moment, L1 network traffics illustrate that the embodiment of the present invention is saved well below L2
Network traffics, reduce network overhead.
By analyzing experimental data, the number of interest bag is being reduced, hop count is reduced, network overhead side is saved
Face, the document transmission method of the embodiment of the present invention has reached expection.
The embodiment of the present invention is in vehicular ad hoc network environment, for the transmission of Large Copacity file between network node, to use
One multiple packet of interest bag correspondence replaces the way of interest bag one packet of correspondence in tradition NDN networks；Not only
Network performance is improved, the efficiency of forwarding is also improved；And the quantity of packet in network is reduced, save network flow
Journey, it is to avoid the network congestion problem brought is possible to when vehicle flowrate increases.
The preferred embodiments of the present invention are these are only, are not intended to limit the invention, for those skilled in the art
For member, the present invention can have various modifications and variations.Any modification within the spirit and principles of the invention, being made,
Equivalent substitution, improvement etc., should be included in the scope of the protection.
Claims (10)
1. a kind of document transmission method applied to vehicular ad hoc network, it is characterised in that methods described includes：
The requestor sends interest bag to turning originator；Wherein, the interest bag include demand file title and it is described please
The numerical value of the corresponding file fragment packet of file is sought, it is described to turn structure of the originator including interest table undetermined and data cached bag
CS；
The originator that turns judges whether the numerical value of respective file fragment data bag in the interest bag is equal to 1；
It is described to turn originator and inquire about the text whether is cached with itself CS if the numerical value of the file fragment packet is not equal to 1
Part fragment data bag；
If the originator that turns is cached with least one described file fragment packet, the originator that turns is in the interest table undetermined
In a newly-built list item be used for recording the interest bag, and the numerical value of the corresponding file fragment packet of the interest bag is assigned to
The fragments counter of the list item, and at least one described file fragment packet is sent to the requestor successively, and often
A packet is sent, the numerical value of the fragments counter subtracts 1；
If described turn the uncached file fragment packet in originator CS, the originator that turns is inquired about in the interest table undetermined
Whether the record of the interest bag is preserved；
When not preserving the record of the interest bag in the interest table undetermined, the originator that turns is built in the interest table undetermined
The list item of the interest bag is found, and forwards the interest bag.
2. according to the method described in claim 1, it is characterised in that methods described also includes：
It is described to turn originator institute in the interest table undetermined when preserving the record of the interest bag in the interest table undetermined
State increase a port number in the interface list of interest bag；
After the fragments counter numerical value for turning originator in the interest table undetermined subtracts 1, in addition to：
If the fragments counter in the interest table undetermined is 0, the originator that turns deletes described in the interest table undetermined
The record of interest bag.
3. according to the method described in claim 1, it is characterised in that methods described also includes：
The producer sends at least one packet and turns originator to described, and the packet is the file fragment that the interest bag is asked
Packet；
The originator that turns judges the packet whether is cached with itself CS；
Turn the uncached packet of originator if described, it is described to turn originator and inquire about in the interest table undetermined whether to preserve
The record of the corresponding interest bag of the packet；
If preserving the record of the corresponding interest bag of the packet in the interest table undetermined, the originator that turns is by the number
The requestor is transmitted to according to bag, while the copy of the packet is buffered in local CS, and often one packet of transmission,
Fragments counter numerical value in the interest table undetermined subtracts 1.
4. method according to claim 3, it is characterised in that the originator that turns judges whether itself is cached with the data
Bag, in addition to：
If the originator that turns preserves the packet, the originator that turns abandons the packet；
The originator that turns inquires about the record for whether having the corresponding interest bag of the packet in the interest table undetermined, also wraps
Include：
It is described to turn described in originator caching if not preserving the record of the corresponding interest bag of the packet in the interest table undetermined
Packet；
After the fragments counter numerical value for turning originator in the interest table undetermined subtracts 1, in addition to：
If the fragments counter in the interest table undetermined is 0, the originator that turns deletes described in the interest table undetermined
The record of the corresponding interest bag of packet.
5. the method according to claim 1-4 any one, it is characterised in that the interest table undetermined includes the interest
The title of demand file, the receiving port number and the fragments counter of the interest bag in bag；Wherein,
The fragments counter is used for the number for counting the file fragment packet that the interest bag correspondence is not yet asked；
The title of the demand file includes protocol name, city name, metropolitan district domain name, request content and request content fragment
Sequence number；
And at least one corresponding described file fragment packet of an interest bag.
6. a kind of file transfer means applied to vehicular ad hoc network, it is characterised in that described device is to turn originator, the forwarding
Person includes communication unit and processing unit；
The communication unit, sends interest bag to turning originator；Wherein, the interest bag includes the title of demand file and described
The numerical value of the corresponding file fragment packet of demand file, it is described to turn structure of the originator including interest table undetermined and data cached bag
CS；
The processing unit, judges whether the numerical value of respective file fragment data bag in the interest bag is equal to 1；
It is described to turn originator and inquire about the text whether is cached with itself CS if the numerical value of the file fragment packet is not equal to 1
Part fragment data bag；
If the originator that turns is cached with least one described file fragment packet, the originator that turns is in the interest table undetermined
In a newly-built list item be used for recording the interest bag, and the numerical value of the corresponding file fragment packet of the interest bag is assigned to
The fragments counter of the list item, and at least one described file fragment packet is sent to the requestor successively, and often
A packet is sent, the numerical value of the fragments counter subtracts 1；
If described turn the uncached file fragment packet in originator CS, the originator that turns is inquired about in the interest table undetermined
Whether the record of the interest bag is preserved；
When not preserving the record of the interest bag in the interest table undetermined, the originator that turns is built in the interest table undetermined
The list item of the interest bag is found, and forwards the interest bag.
7. device according to claim 6, it is characterised in that
The processing unit, is additionally operable to when preserving the record of the interest bag in the interest table undetermined, described to turn originator
Increase a port number in the interface list of interest bag described in the interest table undetermined；
After the fragments counter numerical value for turning originator in the interest table undetermined subtracts 1, in addition to：
If the fragments counter in the interest table undetermined is 0, the originator that turns deletes described in the interest table undetermined
The record of interest bag.
8. device according to claim 6, it is characterised in that
The communication unit, receives at least one packet that the producer sends, and the packet is what the interest bag was asked
File fragment packet；
The processing unit, judges the packet whether is cached with itself CS；
Turn the uncached packet of originator if described, it is described to turn originator and inquire about in the interest table undetermined whether to preserve
The record of the corresponding interest bag of the packet；
If preserving the record of the corresponding interest bag of the packet in the interest table undetermined, the originator that turns is by the number
The requestor is transmitted to according to bag, while the copy of the packet is buffered in local CS, and often one packet of transmission,
Fragments counter numerical value in the interest table undetermined subtracts 1.
9. device according to claim 8, it is characterised in that the processing unit, judge itself whether to be cached with described
Packet, in addition to：
If the originator that turns preserves the packet, the originator that turns abandons the packet；
The originator that turns inquires about the record for whether having the corresponding interest bag of the packet in the interest table undetermined, also wraps
Include：
It is described to turn described in originator caching if not preserving the record of the corresponding interest bag of the packet in the interest table undetermined
Packet；
After the fragments counter numerical value for turning originator in the interest table undetermined subtracts 1, in addition to：
If the fragments counter in the interest table undetermined is 0, the originator that turns deletes described in the interest table undetermined
The record of the corresponding interest bag of packet.
10. the device according to claim 6-9 any one, it is characterised in that the interest table undetermined includes described emerging
The title of demand file, the receiving port number and the fragments counter of the interest bag in interest bag；Wherein,
The fragments counter is used for the number for counting the file fragment packet that the interest bag correspondence is not yet asked；
The title of the demand file includes protocol name, city name, metropolitan district domain name, request content and request content fragment
Sequence number；
And at least one corresponding described file fragment packet of an interest bag.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107580344A (en) * | 2017-09-07 | 2018-01-12 | 华为技术有限公司 | A kind of method, apparatus and system of user terminal switching |
| CN107872400A (en) * | 2017-12-20 | 2018-04-03 | 北京工业大学 | Multi-audio-frequency document distribution method based on NDN in a kind of VANET |
| WO2019096713A1 (en) * | 2017-11-16 | 2019-05-23 | Robert Bosch Gmbh | Method and device for data-oriented information exchange with a vehicle network |
| CN110493885A (en) * | 2019-08-21 | 2019-11-22 | 北京理工大学 | A kind of name data network continuous data method for pushing for data fragmentation |
| CN110572320A (en) * | 2019-08-30 | 2019-12-13 | 湖南科技大学 | Named data single-source multi-path routing method, system and medium based on NDN |
| CN108092899B (en) * | 2018-01-05 | 2020-07-28 | 北京工业大学 | Routing strategy updating method based on named data network under MANET environment |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103581252A (en) * | 2012-07-31 | 2014-02-12 | 华为技术有限公司 | Method, device and system for supporting subscription content of content network |
| CN103747083A (en) * | 2014-01-02 | 2014-04-23 | 北京邮电大学 | Content pushing method based on CCN (Content Centric Network) |
| US20140181226A1 (en) * | 2012-12-21 | 2014-06-26 | Samsung Electronics Co., Ltd. | Content-centric network communication method and apparatus |
| CN104967677A (en) * | 2015-06-05 | 2015-10-07 | 无锡量子云数字新媒体科技有限公司 | File transmission method and apparatus based on NDN cache optimization |
| CN105743983A (en) * | 2016-03-04 | 2016-07-06 | 中山大学 | Named data vehicle-mounted network data distribution method based on navigation route |
| CN105871720A (en) * | 2016-03-24 | 2016-08-17 | 重庆邮电大学 | Method for segmentally forwarding content objectives in content-centric network |
-
2017
- 2017-03-30 CN CN201710203629.XA patent/CN107071015A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103581252A (en) * | 2012-07-31 | 2014-02-12 | 华为技术有限公司 | Method, device and system for supporting subscription content of content network |
| US20140181226A1 (en) * | 2012-12-21 | 2014-06-26 | Samsung Electronics Co., Ltd. | Content-centric network communication method and apparatus |
| CN103747083A (en) * | 2014-01-02 | 2014-04-23 | 北京邮电大学 | Content pushing method based on CCN (Content Centric Network) |
| CN104967677A (en) * | 2015-06-05 | 2015-10-07 | 无锡量子云数字新媒体科技有限公司 | File transmission method and apparatus based on NDN cache optimization |
| CN105743983A (en) * | 2016-03-04 | 2016-07-06 | 中山大学 | Named data vehicle-mounted network data distribution method based on navigation route |
| CN105871720A (en) * | 2016-03-24 | 2016-08-17 | 重庆邮电大学 | Method for segmentally forwarding content objectives in content-centric network |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107580344A (en) * | 2017-09-07 | 2018-01-12 | 华为技术有限公司 | A kind of method, apparatus and system of user terminal switching |
| CN107580344B (en) * | 2017-09-07 | 2021-07-20 | 华为技术有限公司 | Method, device and system for switching user terminal |
| WO2019096713A1 (en) * | 2017-11-16 | 2019-05-23 | Robert Bosch Gmbh | Method and device for data-oriented information exchange with a vehicle network |
| CN107872400A (en) * | 2017-12-20 | 2018-04-03 | 北京工业大学 | Multi-audio-frequency document distribution method based on NDN in a kind of VANET |
| CN107872400B (en) * | 2017-12-20 | 2021-04-09 | 北京工业大学 | NDN-based multi-audio file distribution method in VANET |
| CN108092899B (en) * | 2018-01-05 | 2020-07-28 | 北京工业大学 | Routing strategy updating method based on named data network under MANET environment |
| CN110493885A (en) * | 2019-08-21 | 2019-11-22 | 北京理工大学 | A kind of name data network continuous data method for pushing for data fragmentation |
| CN110572320A (en) * | 2019-08-30 | 2019-12-13 | 湖南科技大学 | Named data single-source multi-path routing method, system and medium based on NDN |
| CN110572320B (en) * | 2019-08-30 | 2022-03-15 | 湖南科技大学 | Named data single-source multi-path routing method, system and medium based on NDN |
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