CN103812933A - Bipartite graph based in-vehicle network distributed storage method - Google Patents

Abstract

The invention discloses a bipartite graph based in-vehicle network distributed storage method. According to the bipartite graph based in-vehicle network distributed storage method, a distributed storage problem is firstly modeled, and bipartite graph matching is performed, so that optimal in-vehicle network distributed storage of in-vehicle request identification information sent by each in-vehicle node can be achieved under different conditions, and in-vehicle network can respond to maximum in-vehicle request identification information; subsequently, repeated network information stored by roadside units is cleared, resource waste generated by the fact that multiple roadside units respond to the same in-vehicle request identification information is avoided, and meanwhile, in-vehicle request identification information which is met is not affected; finally, in-vehicle request identification information which is not met is collected, and secondary allocation is performed on spare storage space obtained by clearing the roadside units until each roadside unit has no spare storage space, or all the in-vehicle request identification information received by the roadside units is responded, or remaining in-vehicle request identification information cannot be met; a storage resource utilization rate and a data response data are increased, and data service qualities of an in-vehicle network are guaranteed.

Description

Vehicle-mounted network distributed storage method based on bipartite graph

Technical Field

The invention relates to a distributed storage method of a vehicle-mounted network based on a bipartite graph, in particular to a distributed storage method of a vehicle-mounted network based on a bipartite graph in a scene formed by roadside infrastructure and mobile vehicles.

Background

Version 1 of 5 months, 2010, Dongdong, Zhouyi, ed, "computer Algorithm and Programming practice", page 334. G is said to be a bipartite graph if the set of vertices of the graph G can be divided into two parts, X and Y, such that the two endpoints of each edge in G are one in X and the other in Y. X and Y are two divisions of G, denoted as G ═ X, Y, E, and E is a side.

The vehicle-mounted network is composed of a mobile vehicle, a fixed roadside infrastructure on which intelligent devices (called roadside units) with large storage capacity capable of communicating with the information center are deployed, and an information center on which sensor nodes (called vehicle-mounted nodes) with sensing, data processing, storage and wireless communication capabilities are deployed. The vehicle-mounted network realizes wide coverage of information transmission, expands the range and depth of information transmission and simplifies large-scale network deployment through communication (V2I) between vehicle-mounted nodes and roadside units and communication (V2V) between the vehicle-mounted nodes. The vehicle-mounted network has the characteristics of high-speed movement of vehicle-mounted nodes, regularity of vehicle movement, network access support of roadside units and the like, is wide in application range, and can be used for various intelligent services such as safety early warning, driving assistance, distributed traffic information release, multimedia information sharing and entertainment and the like, so that the driving safety and the traffic transportation efficiency are greatly improved. Reference 6 is made to V2V and V2I communication modes.

Communication between the on-board node and the roadside units (V2I) is an important communication mode in the on-board network, and in the V2I communication mode, the roadside units can acquire network information from an information center and store the network information in a local device, and the on-board node can transmit on-board request identification information to the roadside units and receive the network information transmitted by the roadside units. In the process, how the information center decides which network information is distributed to which roadside units to respond to as many vehicle-mounted request identification information as possible is a key problem.

Due to the fact that the vehicle runs to cause rapid change of the topology of the vehicle-mounted network, the storage space of the roadside unit is limited, and the same network information can be requested by a plurality of vehicle-mounted nodes, so that the optimal distributed storage method of the vehicle-mounted network becomes an NPC (non-deterministic polymeric complete) problem, cannot be solved in polynomial time, and has no practical value. Therefore, how to design an efficient vehicle-mounted network distributed storage method, how to calculate the storage condition of network information in the roadside unit within polynomial time, and how to ensure higher data response rate, and how to improve the quality of vehicle-mounted network data service become important and difficult points of research.

Disclosure of Invention

In order to improve the data response rate of the distributed storage of the vehicle-mounted network and reduce the time overhead of the storage scheme calculation, the invention adopts a distributed storage method of the vehicle-mounted network based on a bipartite graph. The method firstly models the distributed storage problem, and utilizes bipartite graph matching to realize the optimal distributed storage method of the vehicle-mounted network under different conditions for the vehicle-mounted request identification information sent by each vehicle-mounted node, thereby ensuring that the vehicle-mounted network can respond to the most vehicle-mounted request identification information; then, the repeated network information stored by the roadside units is cleaned, so that resource waste caused by the fact that a plurality of roadside units respond to the same vehicle-mounted request identification information is avoided, and meanwhile the satisfied vehicle-mounted request identification information is not influenced; and finally, collecting the unsatisfied vehicle-mounted request identification information, and carrying out secondary distribution on the vacant storage space obtained by the roadside unit cleaning until each roadside unit has no vacant storage space, or all the vehicle-mounted request identification information received by the roadside unit is responded, or the remaining vehicle-mounted request identification information cannot be satisfied. The method of the invention improves the utilization rate of storage resources and the data response rate, and ensures the data service quality of the vehicle-mounted network.

The invention relates to a distributed storage method of a vehicle-mounted network based on a bipartite graph, which comprises the following steps:

the method comprises the following steps: two-part diagram of structure

Firstly, setting an empty bipartite graph G as (X, Y, E), wherein X represents a left vertex, Y represents a right vertex, and E represents an edge; then, filling elements into X of the empty bipartite graph G ═ X, Y, E), and forming a bipartite graph G with left vertices^X(ii) a Then, a storage position with storage capacity is constructed and filled in the bipartite graph G with the left vertex^XIn Y of (3), a bipartite graph G having left and right vertex sets is formed^X+Y(ii) a Finally matching the condition by the vertex

And isAnd is

To judge the bipartite graph G with left and right vertex sets^X+YWhether X and Y in (1) are connected to each other or not is judged, and a bipartite graph with vertexes and edges is obtained

Step two: finding a bipartite graph maximum matching subgraph

If there are vertices and edges

If the edge set E is not empty, the Hungarian algorithm is adopted to obtain the maximum matching subgraph GB ═<(X,Y),EB>(ii) a If there are vertices and edges

The edge set E of (a) is empty,ending the distributed storage and outputting a vehicle-mounted distribution result DI;

step three: distributing and cleaning network information

For the maximum matching subgraph GB ═<(X,Y),EB>Network information distribution is carried out, and a vehicle-mounted distribution result is obtained <math> <mrow> <msup> <mrow> <mi>DI</mi> <mo>=</mo> <mo>{</mo> <mi>d</mi> </mrow> <msup> <mi>Rf</mi> <mn>1</mn> </msup> </msup> <mo>,</mo> <msup> <mi>d</mi> <msup> <mi>Rf</mi> <mn>2</mn> </msup> </msup> <mo>,</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> </mrow> <mrow> <msup> <mi>d</mi> <msup> <mi>Rf</mi> <mi>z</mi> </msup> </msup> <mo>}</mo> <mo>;</mo> </mrow></math>Then judge one by one the <math> <mrow> <msup> <mrow> <mi>DI</mi> <mo>=</mo> <mo>{</mo> <mi>d</mi> </mrow> <msup> <mi>Rf</mi> <mn>1</mn> </msup> </msup> <mo>,</mo> <msup> <mi>d</mi> <msup> <mi>Rf</mi> <mn>2</mn> </msup> </msup> <mo>,</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> </mrow> <mrow> <msup> <mi>d</mi> <msup> <mi>Rf</mi> <mi>z</mi> </msup> </msup> <mo>}</mo> </mrow></math>Whether the number of roadside units in each element is more than 1 or not; if the number of the roadside units is larger than 1, cleaning vehicle-mounted nodes corresponding to the same network information of different roadside units; if the number of the roadside units is less than or equal to 1, giving up cleaning of the network information distributed by the roadside units; then, the cleaned roadside units are sorted according to the number of the vehicle-mounted nodes, and the sorted roadside units are respectively processed into a first position and other positions; to pairThe storage position of the roadside unit at the head position is reserved, whether the roadside units at other positions behind the head position are empty is judged, the empty is a recording storage position, and cleaning is abandoned if the roadside units are not empty; then, the assignment of the vehicle-mounted node is carried out on the intermediate result obtained by cleaning;

step four: secondary distribution and updating bipartite graph vertex set

Removing vehicle-mounted request identification informationThe digital identification number related to the left vertex of the connecting edge is obtained to obtain the secondarily distributed vehicle-mounted request identification information

WhereinAdding an element Z into the identification of the left vertex of the empty bipartite graph; and finally, adding elements in the secondarily distributed storage positions of the whole network into the right vertex of the bipartite graph, thereby realizing the distribution of the secondary distribution.

The distributed storage method of the vehicle-mounted network based on the bipartite graph has the following advantages:

1. the distributed storage problem of the vehicle-mounted network is converted into the maximum matching problem of the bipartite graph based on the bipartite graph, the calculation complexity of solving is reduced, and the distribution scheme can be calculated in polynomial time.

2. According to the invention, the vehicle-mounted nodes and the roadside units are mapped to the left and right vertexes of the bipartite graph, and the corresponding relation between the vehicle-mounted request identification information and the storage positions of the roadside units is represented by connecting the left and right vertexes, so that the network information distribution of the information center is more visual, and the problem description and display are clearer.

3. The method avoids resource waste caused by different roadside units responding to the same vehicle-mounted request identification information by clearing redundant allocation, and improves the utilization rate of the vehicle-mounted network storage space.

4. The method of the invention carries out secondary distribution on the vacant storage space generated by the roadside unit cleaning until each roadside unit has no vacant storage space, or all the vehicle-mounted request identification information of the roadside unit is responded, or the rest vehicle-mounted request identification information cannot be met, thereby improving the response rate of the data request and ensuring the data service quality of the vehicle-mounted network.

Drawings

Fig. 1 is a process flow diagram of distributed storage of a conventional in-vehicle network.

FIG. 2 is a flow chart of the distributed storage of the vehicular network based on the bipartite graph of the invention.

Fig. 3 is a schematic diagram of an onboard network formed by a plurality of onboard nodes and roadside units in the current storage period.

Fig. 3A is a schematic diagram of an onboard network formed by a plurality of onboard nodes and roadside units in the next storage cycle.

FIG. 4A is a schematic diagram of the relationship between the left and right vertices and the edge of the bipartite graph according to the present invention.

Fig. 4B is a diagram of the maximum matching subgraph of fig. 4A.

FIG. 4C is a schematic diagram of the two-part diagram of FIG. 4B after cleaning.

Fig. 4D is a schematic diagram of the left and right vertices of the bipartite graph when performing quadratic allocation.

FIG. 5 is a graph comparing data response rate of the present invention method with other methods for in-vehicle network distributed storage.

FIG. 6 is a comparison graph of average response time delay for in-vehicle network distributed storage by the method of the present invention and other methods.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.

Referring to fig. 1, a conventional vehicle-mounted network system includes a plurality of roadside units, a plurality of vehicle-mounted nodes, and an information center IC; the communication between the vehicle-mounted nodes and the roadside units is V2I, the communication between the vehicle-mounted nodes is V2V, and the communication between the information center IC and the roadside units is an Internet network. The network information stored in the information center IC is divided into two parts, one part is the vehicle-mounted network information content, the other part is the number identification number ID corresponding to the vehicle-mounted network information content, the ID is 1,2, …, Z represents the number of the number identification numbers, for convenience of the following description, Z also represents any number identification number, and may also be the number identification number corresponding to the last vehicle-mounted network information content. If the network information is expressed in a tabular form, the following table is provided.

Sequence number	content	ID
			Rf1	content1	1
Rf2	content2	2
			Rf3	content3	3
Rf4	content4	4
			Rf5	content5	5
┋	┋	┋
			RfZ-1	contentZ-1	Z-1
RfZ	contentZ	Z

In the above table, content₁、content₂、content₃、content₄、content₅、……、content_Z-1And content_ZThe specific in-vehicle network information content of (a) is different.

The first network information is denoted Rf¹(content₁,1)，content₁Representing the vehicle-mounted network information content with thenumber identification number 1, 1 representing the number corresponding to the first vehicle-mounted network information contentAn identification number;

the second network information is denoted as Rf²(content₂,2)，content₂The number identification number of the vehicle-mounted network information content is 2, and 2 is the number identification number corresponding to the second vehicle-mounted network information content;

the third network information is denoted as Rf³(content₃,3)，content₃The number identification number of the third vehicle-mounted network information content is 3, and 3 is a number identification number corresponding to the third vehicle-mounted network information content;

the fourth network information is denoted Rf⁴(content₄,4)，content₄The number identification number of the fourth vehicle-mounted network information content is 4, and 4 is a number identification number corresponding to the fourth vehicle-mounted network information content;

the fifth network information is denoted as Rf⁵(content₅,5)，content₅The vehicle-mounted network information content with the number identification number of 5 is shown, and 5 is a number identification number corresponding to the fifth vehicle-mounted network information content;

the Z-1 st network information is recorded as Rf^Z-1(content_Z-1,Z-1)，content_Z-1The method comprises the steps that the vehicle-mounted network information content with the number identification number Z-1 is represented, and Z-1 represents the number identification number corresponding to the Z-1 th vehicle-mounted network information content;

the last network information is denoted Rf^Z(content_Z,Z)，content_ZThe method comprises the steps that vehicle-mounted network information content with a digital identification number Z is represented, and the Z represents a digital identification number corresponding to the last vehicle-mounted network information content; for convenience of explanation, Rf^Z(content_ZZ) is also referred to as any network information.

In any storage period tau, the network information is expressed as a set

<math> <mrow> <msup> <mi>F</mi> <mi>&tau;</mi> </msup> <mo>=</mo> <mfenced open='{' close='}'> <mtable> <mtr> <mtd> <msup> <mi>Rf</mi> <mn>1</mn> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mn>1</mn> </msub> <mo>,</mo> <mn>1</mn> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mn>2</mn> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mn>2</mn> </msub> <mo>,</mo> <mn>2</mn> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mn>3</mn> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mn>3</mn> </msub> <mo>,</mo> <mn>3</mn> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mn>4</mn> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mn>4</mn> </msub> <mo>,</mo> <mn>4</mn> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mn>5</mn> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mn>5</mn> </msub> <mo>,</mo> <mn>5</mn> <mo>)</mo> </mrow> </mtd> </mtr> <mtr> <mtd> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mrow> <mi>Z</mi> <mo>-</mo> <mn>1</mn> </mrow> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mrow> <mi>Z</mi> <mo>-</mo> <mn>1</mn> </mrow> </msub> <mo>,</mo> <mi>Z</mi> <mo>-</mo> <mn>1</mn> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mi>Z</mi> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mi>Z</mi> </msub> <mo>,</mo> <mi>Z</mi> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> </mtable> </mfenced> <mo>.</mo> </mrow></math>

In the vehicle-mounted network, a current storage cycle is denoted as τ (also referred to as an arbitrary storage cycle τ), and a next storage cycle is denoted as τ + 1. The information transmission processing flow of a vehicle-mounted network comprises the following steps: firstly, in the driving process of a vehicle-mounted node, in the current storage period tau, the vehicle-mounted node sends vehicle-mounted request identification information IM to an information center IC through a roadside unit; then, when the current storage period tau is over, the information center IC distributes network information corresponding to the IM to the roadside units, and outputs a vehicle-mounted distribution result DI; and finally, in the driving process of the vehicle-mounted node, in the next storage period tau +1, the vehicle-mounted node acquires network information corresponding to the IM from the encountered roadside unit.

Referring to fig. 1 and 2, in order to improve the data response rate of the vehicle-mounted network distributed storage and reduce the time overhead of the storage scheme calculation, the invention adopts a vehicle-mounted network distributed storage method based on a bipartite graph, which is referred to as ccr (cooperative Content replication) method for short. The CCR method is used for solving the problem that an information center IC distributes network information corresponding to IM to roadside units.

And the information center IC of the vehicle-mounted network can acquire the network information corresponding to the vehicle-mounted request identification information IM through the Internet and distribute the network information to the roadside units so as to respond to the vehicle-mounted request identification information of the vehicle-mounted nodes.

In the vehicle-mounted network, r roadside units are arranged in total and are expressed in a set form

RD＝{R¹,R²,…,R^r}，R¹Denotes a first roadside unit, R²Denotes a second roadside unit, R^rThe last roadside unit is shown, R for ease of illustration^rAlso referred to as any roadside unit. In the vehicle network, any one roadside unit R^rHas a certain storage capacity

Represents a roadside unit R^rThe unit of the possessed network information capacity is the size of one network information.

In the vehicle-mounted network, a total of n vehicle-mounted nodes are provided, and the nodes are expressed in a set form as VD ═ V¹,V²,…,Vⁿ}，V¹Denotes the first vehicle node, V²Represents a second vehicle node, VⁿThe last vehicle node is shown, V for ease of illustrationⁿAlso referred to as any one of the on-board nodes.

In the vehicle network, in the next storage period tau +1, the first vehicle node V¹Record the set of roadside units to be encountered

Second vehicle node V²Record the set of roadside units to be encountered

Last vehicle node VⁿRecord the set of roadside units to be encountered <math> <mrow> <msup> <mi>AR</mi> <msup> <mi>V</mi> <mi>n</mi> </msup> </msup> <mo>&SubsetEqual;</mo> <mi>RD</mi> <mo>.</mo> </mrow></math>

In the current storage period tau, the first vehicle-mounted node V¹By roadside unit set RD ═ R¹,R²,…,R^rRecording the vehicle-mounted request identification information sent to the information center IC

The vehicle-mounted request identification informationIs referred to as F^τBy the first vehicle-mounted node V¹And the requested digital identification number ID corresponding to the vehicle-mounted network information content.

In the current storage period tau, the second vehicle-mounted node V²By roadside unit set RD ═ R¹,R²,…,R^rRecording the vehicle-mounted request identification information sent to the information center IC

The vehicle-mounted request identification information

Is referred to as F^τIn the second vehicle node V²And the requested digital identification number ID corresponding to the vehicle-mounted network information content.

In the current storage period tau, the last vehicle-mounted node VⁿBy roadside unit set RD ═ R¹,R²,…,R^rRecording the vehicle-mounted request identification information sent to the information center IC

The vehicle-mounted request identification information

Is referred to as F^τLast vehicle-mounted node V inⁿAnd the requested digital identification number ID corresponding to the vehicle-mounted network information content.

In the invention, all vehicle-mounted nodes VD ═ V¹,V²,…,VⁿThe vehicle-mounted request identification information sent by the station is expressed as <math> <mrow> <mi>IM</mi> <mo>=</mo> <mo>{</mo> <msup> <mi>I</mi> <msup> <mi>V</mi> <mn>1</mn> </msup> </msup> <mo>,</mo> <msup> <mi>I</mi> <msup> <mi>V</mi> <mn>2</mn> </msup> </msup> <mo>,</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>,</mo> <msup> <mi>I</mi> <msup> <mi>V</mi> <mi>n</mi> </msup> </msup> <mo>}</mo> <mo>.</mo> </mrow></math>

Referring to fig. 3, in an on-board network scenario, 7 roadside units and 7 on-board nodes are provided.

First roadside unit R¹Storage capacity of

Second roadside unit R²Storage capacity of

Third roadside unit R³Storage capacity of

The fourth roadside unit R⁴Storage capacity of

The fifth roadside unit R⁵Storage capacity of

The R-1 th roadside unit R^r-1Storage capacity of

The R roadside units R^rStorage capacity of

In the current storage period tau, the first vehicle-mounted node V¹The passing roadside unit has a first roadside unit R¹. First vehicle node V¹To the first roadside unit R¹Transmitted in-vehicle request identification information

In the current storage period tau, the second vehicle-mounted node V²The passing roadside unit has a first roadside unit R¹. Second vehicle node V²To the first roadside unit R¹Transmitted in-vehicle request identification information

In the current storage period tau, a third vehicle-mounted node V³The passing roadside unit has a second roadside unit R². Third vehicle node V³To a second roadside unit R²Transmitted in-vehicle request identification information

In the current storage period tau, the fourth vehicle-mounted node V⁴The passing roadside unit has a fourth roadside unit R⁴. Fourth vehicle node V⁴To a fourth roadside unit R⁴Transmitted in-vehicle request identification information

In the current storage period tau, the fifth vehicle-mounted node V⁵The passing roadside unit has a third roadside unit R³The fourth roadside unit R⁴. Fifth vehicle node V⁵To a third roadside unit R³And a fourth roadside unit R⁴Transmitted in-vehicle request identification information

In the current storage period tau, the n-1 th vehicle-mounted node V^n-1The passing roadside unit has the R-1 th roadside unit R^r-1. N-1 th vehicle-mounted node V^n-1To the r-1 stRoadside unit R^r-1Transmitted in-vehicle request identification information$I^{V^{n-1}}=\{Z-1\}.$

In the current storage period tau, the nth vehicle-mounted node VⁿThe passing roadside unit has a first roadside unit R¹A second roadside unit R². Nth vehicle node VⁿTo the first roadside unit R¹And a second roadside unit R²Transmitted in-vehicle request identification information

Referring to fig. 3A, in an on-board network scenario, 7 roadside units and 7 on-board nodes are provided.

In the next storage period tau +1, the first vehicle node V¹The roadside unit to be encountered has a second roadside unit R²Is marked as

In the next memory period tau +1, the second vehicle node V²The roadside unit to be encountered has a fourth roadside unit R⁴A third roadside unit R³Is marked as

In the next storage period tau +1, the third vehicle node V³The roadside unit to be encountered has a fifth roadside unit R⁵Is marked as

In the next storage period tau +1, the fourth on-board node V⁴The roadside unit to be met has the R-1 th roadside unit R^r-1The R < th > roadside unit R^rIs marked as

In the next storage period tau +1, the fifth vehicle node V⁵The roadside unit to be encountered has a fifth roadside unit R⁵Is marked as

In the next storage period tau +1, the n-1 th vehicle-mounted node V^n-1The roadside unit to be encountered has the R-th roadside unit R^rThe fifth roadside unit R⁵Is marked as

In the next storage period tau +1, the nth vehicle-mounted node VⁿThe roadside unit to be encountered has a fifth roadside unit R⁵The R < th > roadside unit R^rIs marked as

In order to describe in detail the vehicle-mounted network distributed storage based on the bipartite graph of the received network information by the information center IC, the present invention uses an example to describe how the network information is distributed stored, which is only used for illustrating but not limiting the technical solution of the present invention, and any modification or partial replacement without departing from the spirit and scope of the present invention shall be covered in the protection scope of the technical solution of the present invention.

Referring to fig. 2, the specific steps of a distributed storage method (CCR method) for a vehicle network based on a bipartite graph provided by the present invention are as follows:

the method comprises the following steps: two-part diagram of structure

Step 11: setting an empty bipartite graph as G ═ X, Y, E, X denotes the left vertex, Y denotes the right vertex, and E denotes the edge; executing step 12;

step 12: collected from information centre IC in current storage period tau

The element in (b) is added to X of (X, Y, E) to obtain a bipartite graph G with a left vertex^XExecuting step 13;

referring to FIGS. 4A, 4B, and 4C, a bipartite graph G having a left vertex according to the present invention^XX ═ a is an element contained in the left vertex of (a)₁,a₂,a₃,a₄,a₅,a₆,a₇,…,a_i-1,a_i}, wherein:

a₁denotes the first left vertex, a₁The recorded content is

Thenumerical identification number 1 contained in (a);

a₂denotes the second left vertex, a₂The recorded content is

Thenumerical identification number 2 contained in (a);

a₃denotes the third left vertex, a₃The recorded content is

Thenumerical identification number 1 contained in (a);

a₄denotes the fourth left vertex, a₄Inside of recordContaining is

The numerical identification number 3 contained therein;

a₅denotes the fifth left vertex, a₅The recorded content is

Thenumerical identification number 4 contained therein;

a₆denotes the sixth left vertex, a₆The recorded content is

The numerical identification number 5 contained therein;

a₇denotes the seventh left vertex, a₇The recorded content is

The numerical identification number Z-1 contained in (a);

a_i-1denotes the i-1 th left vertex, a_i-1The recorded content is

Thenumerical identification number 1 contained in (a);

a_irepresents the last left vertex, a_iThe recorded content is

The numerical identification number Z contained in (a);

for convenience of explanation, a_iAlso referred to as any left vertex, i represents the identification number of the left vertex.

Step 13: aiming at any roadside unit R in the vehicle-mounted network^rOne size is constructed as a storage capacity

Set of storage locations, as

Wherein,

represents R^rIs stored in the first storage location of the memory,represents R^rIs stored in the first storage location of the memory,represents R^rTo the last storage location, step 14 is performed;

the storage position refers to a place where network information can be stored in any roadside unit, each roadside unit comprises one or more storage positions, and each storage position only stores one piece of network information.

Step 14: traverse all RD ═ R¹,R²,…,R^rObtaining a whole network storage position set by the roadside units in the <math> <mrow> <msup> <mi>UD</mi> <mi>RD</mi> </msup> <mo>=</mo> <mo>{</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>1</mn> </msup> </msup> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>2</mn> </msup> </msup> <mo>&cup;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mi>r</mi> </msup> </msup> <mo>}</mo> <mo>;</mo> </mrow></math>And will be <math> <mrow> <msup> <mi>UD</mi> <mi>RD</mi> </msup> <mo>=</mo> <mo>{</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>1</mn> </msup> </msup> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>2</mn> </msup> </msup> <mo>&cup;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mi>r</mi> </msup> </msup> <mo>}</mo> </mrow></math>Element(s) in (b) is added to bipartite graph G with left vertices^XIn Y of (3), a bipartite graph G having left and right vertex sets is obtained^X+YExecuting step 15;

in the present invention, referring to fig. 4A, 4B, and 4C, a bipartite graph G having left and right vertex sets^X+YY ═ b₁,b₂,b₃,b₄,b₅,b₆,b₇,b₈,…,b_j-1,b_j}, wherein:

b₁representing the first right vertex, b₁The recorded content is R¹First storage location of

b₂Representing the second right vertex, b₂The recorded content is R²First storage location of

b₃Represents the third right vertex, b₃The recorded content is R³First storage location of

b₄Represents the fourth right vertex, b₄The recorded content is R⁴First storage location of

b₅Represents the fifth right vertex, b₅The recorded content is R⁵First storage location of

b₆Denotes the sixth right vertex, b₆The recorded content is R⁵Second storage location of

b₇Denotes the seventh right vertex, b₇The recorded content is R⁵Third storage location of

b₈Denotes the eighth right vertex, b₈The recorded content is R^r-1First storage location of

b_j-1Represents the j-1 th right vertex, b_j-1The recorded content is R^rFirst storage location of

b_jRepresenting the last right vertex, b_jThe recorded content is R^rSecond storage location of

For convenience of explanation, b_jAlso called any one right vertex, j represents the identification number of the right vertex。

Step 15: matching conditions with vertices

And is

And is

To judge the bipartite graph G with left and right vertex sets^X+YWhether X and Y in (1) are connected with each other is judged, so that a bipartite graph with vertexes and edges is constructed

Executing step 21;

if a_iAnd b_jSatisfy the vertex matching condition

And isAnd is

Then at G^X+YThe edge set E of (1) adds edges<a_i,b_j>；

If a_iAnd b_jNot satisfying vertex matching conditions

And is

And is

Then abandon the adding of the edge<a_i,b_j>；

See FIG. 4A for a₁And b₂Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₁,b₂>；

a₂And b₃Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₂,b₃>；a₂And b₄Satisfy the vertex matching conditionAnd is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₂,b₄>；

a₃And b₅Satisfy the vertex matching condition

And isAnd is

Then at G^X+YThe edge set E of (1) adds edges<a₃,b₅>；a₃And b₆Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₃,b₆>；a₃And b₇Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₃,b₇>；

a₄And b₅Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₄,b₅>；a₄And b₆Satisfy the vertex matching condition

And is

And isThen at G^X+YThe edge set E of (1) adds edges<a₄,b₆>；a₄And b₇Satisfy the vertex matching condition

And isAnd is

Then is at

The edge set E of (1) adds edges<a₄,b₇>；

a₅And b₈Satisfy the vertex matching condition

And isAnd is

Then at G^X+YThe edge set E of (1) adds edges<a₅,b₈>；a₅And b_j-1Satisfy the vertex matching condition

And is

And isThen at G^X+YThe edge set E of (1) adds edges<a₅,b_j-1>；a₅And b_jSatisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₅,b_j>；

a₆And b₅Satisfy the vertex matching condition

And isAnd is

Then at G^X+YThe edge set E of (1) adds edges<a₆,b₅>；a₆And b₆Satisfy the vertex matching condition

And is

And isThen at G^X+YThe edge set E of (1) adds edges<a₆,b₆>；a₆And b₇Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₆,b₇>；

a₇And b₅Satisfy the vertex matching condition

And isAnd is

Then at G^X+YThe edge set E of (1) adds edges<a₇,b₅>；a₇And b₆Satisfy the vertex matching condition

And is

And isThen at G^X+YThe edge set E of (1) adds edges<a₇,b₆>；a₇And b₇Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₇,b₇>；a₇And b_j-1Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₇,b_j-1>；a₇And b_jSatisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₇,b_j>；

a_i-1And b₅Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i-1,b₅>；a_i-1And b₆Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i-1,b₆>；a_i-1And b₇Satisfy the vertex matching conditionAnd isAnd is

Then at G^X+YThe edge set E of (1) adds edges<a_i-1,b₇>；a_i-1And b_j-1Satisfy the vertex matching condition

And is

And isThen at G^X+YThe edge set E of (1) adds edges<a_i-1,b_j-1>；a_i-1And b_jSatisfy the vertex matching conditionAnd is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i-1,b_j>；

a_iAnd b₅Satisfy the vertex matching conditionAnd is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i,b₅>；a_iAnd b₆Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i,b_>；a_iAnd b₇Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i,b₇>；a_iAnd b_j-1Satisfy the vertex matching condition

And is

And isThen at G^X+YThe edge set E of (1) adds edges<a_i,b_j-1>；a_iAnd b_jSatisfy the vertex matching conditionAnd is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i,b_j>。

The edge in the statistical edge set E comprises<a₁,b₂>、<a₂,b₃>、<a₂,b₄>、<a₃,b₅>、<a₃,b₆>、<a₃,b₇>、<a₄,b₅>、<a₄,b₆>、<a₄,b₇>、<a₅,b₈>、<a₅,b_j-1>、<a₅,b_j>、<a₆,b₅>、<a₆,b₆>、<a₆,b₇>、<a₇,b₅>、<a₇,b₆>、<a₇,b₇>、<a₇,b_j-1>、<a₇,b_j>、<a_i-1,b₅>、<a_i-1,b₆>、<a_i-1,b₇、<a_i-1,b_j-1>、<a_i-1,b_j>、<a_i,b₅>、<a_i,b₆>、<a_i,b₇>、<a_i,b_j-1>And<a_i,b_j>。

in the invention, by establishing an empty bipartite graph model and taking the vehicle-mounted request identification information of the vehicle-mounted node and the storage positions of the roadside units as the left vertex and the right vertex of the bipartite graph respectively, the distributed storage problem of the vehicle-mounted network is converted into the maximum matching problem of the bipartite graph.

Step two: finding a bipartite graph maximum matching subgraph

Step 21: if there are vertices and edges

If the edge set E is not empty, step 22 is executed;

if there are vertices and edges

If the edge set E is empty, ending the distributed storage and outputting a vehicle-mounted distribution result DI;

step 22: applying the Hungarian algorithm from bipartite graphs with vertices and edgesObtaining maximum matching subgraph GB ═<(X,Y),EB>Where EB is a bipartite graph with vertices and edges

A subset of the edge set E (EB is simply referred to as an edge subset); EB ═ tone<γ,β>I γ ∈ X, β ∈ Y }, where γ denotes the maximum matching subgraph GB ═ Y }<(X,Y),EB>The left vertex of any one edge in the edge set EB, and beta represents the maximum matching subgraph GB ═<(X,Y),EB>The right vertex of any one edge in the edge set EB; step 31 is performed.

Referring to FIG. 4B, the edges in the edge subset EB include<a₁,b₂>、<a₂,b₃>、<a₃,b₅>、<a₄,b₆>、<a₅,b₈>、<a₆,b₇>、<a₇,b_j-1>And<a_i-1,b_j>. Gamma includes an edge<a₁,b₂>A in (a)₁Edge of<a₂,b₃>A in (a)₂Edge of<a₃,b₅>A in (a)₃Edge of<a₄,b₆>A in (a)₄Edge of<a₅,b₈>A in (a)₅Edge of<a₆,b₇>A in (a)₆Edge of<a₇,b_j-1>A in (a)₇And edge<a_i-1,b_j>A in (a)_i-1. Then beta includes an edge<a₁,b₂>B in (1)₂Edge of<a₂,b₃>B in (1)₃Edge of<a₃,b₅>B in (1)₅Edge of<a₄,b₆>B in (1)₆Edge of<a₅,b₈>B in (1)₈Edge of<a₆,b₇>B in (1)₇Edge of<a₇,b_j-1>B in (1)_j-1And edge<a_i-1,b_j>B in (1)_j。

In the invention, the Hungarian algorithm is utilized to convert the determination of the distributed storage allocation technical scheme into the searching of the maximum matching subgraph of the bipartite graph, so that the calculation complexity of the network center of the vehicle-mounted network on the received network information is reduced, and the distributed storage allocation technical scheme can be determined in polynomial time.

Step three: distributing and cleaning network information

Step 31: will one side at will<a_i,b_j>The network information corresponding to the left vertex in the system is distributed to the roadside unit corresponding to the right vertex, and after the distribution of all the network information is finished, the vehicle-mounted distribution result is obtained <math> <mrow> <msup> <mrow> <mi>DI</mi> <mo>=</mo> <mo>{</mo> <mi>d</mi> </mrow> <msup> <mi>Rf</mi> <mn>1</mn> </msup> </msup> <mo>,</mo> <msup> <mi>d</mi> <msup> <mi>Rf</mi> <mn>2</mn> </msup> </msup> <mo>,</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> </mrow> <mrow> <msup> <mi>d</mi> <msup> <mi>Rf</mi> <mi>z</mi> </msup> </msup> <mo>}</mo> <mo>,</mo> </mrow></math>Step 32 is executed;

referring to FIG. 4B, the edge is cut<a₁,b₂>First left vertex a in (1)₁Corresponding Rf¹Assigned to the second right vertex b₂Corresponding R²Performing the following steps;

will edge<a₂,b₃>Second left vertex a in (1)₂Corresponding Rf²Is assigned to the third right vertex b₃Corresponding R³Performing the following steps;

will edge<a₃,b₅>Third left vertex a in (1)₃Corresponding Rf¹Assigned to the fifth right vertex b₅Corresponding R⁵Performing the following steps;

will edge<a₄,b₆>The fourth left vertex a in₄Corresponding Rf³Assigned to the sixth right vertex b₆Corresponding R⁵Performing the following steps;

will edge<a₅,b₈>The fifth left vertex a in₅Corresponding Rf⁴Is assigned to the eighth right vertex b₈Corresponding R^r-1Performing the following steps;

will edge<a₆,b₇>The sixth left vertex a in₆Corresponding Rf⁵Assigned to the seventh right vertex b₇Corresponding R⁵Performing the following steps;

will edge<a₇,b_j-1Seventh left vertex a in₇Corresponding Rf^Z-1Is distributed to the j-1 th right vertex b_j-1Corresponding R^rPerforming the following steps;

will edge<a_i-1,b_j>The ith-1 left vertex a in_i-1Corresponding Rf¹Is assigned to the jth right vertex b_jCorresponding R^rIn (1).

Referring to fig. 4B, the first network information Rf is assigned¹The roadside unit has a second roadside unitR is a member of²The fifth roadside unit R⁵The R < th > roadside unit R^rFirst on-board distributionresult$d^{{\mathrm{Rf}}^{}}$${{}^1}^{}=\{{\mathrm{<figure-callout\; label="R"\; filenames="HDA0000462146700000051.png"\; state="\{\{state\}\}">R</figure-callout>}}^2,R^5,R^r\}.$

Second network information Rf is assigned²The roadside unit has a third roadside unit R³Simply called second on-board distributionresult$d^{{\mathrm{Rf}}^{}}$${{}^2}^{}=\left\{R^3\right\}.$

Third network information Rf is assigned³The roadside unit has a fifth roadside unit R⁵Short third on-board distribution results$d^{{\mathrm{Rf}}^3}=\left\{R^5\right\}.$

Fourth network information Rf is assigned⁴The roadside unit has the R-1 th roadside unit R^r-1Fourth on-board distributionresult$d^{{\mathrm{Rf}}^{}}$${{}^4}^{}=\left\{R^{r-1}\right\}.$

Fifth network information Rf is assigned⁵The roadside unit has a fifth roadside unit R⁵Fifth vehicle distribution result for short$d^{{\mathrm{Rf}}^5}=\left\{R^5\right\}.$

Z-1 th network information Rf is assigned^Z-1The roadside unit has an R-th roadside unit R^rZ-1 th vehicle distribution result

Z-th network information Rf is assigned^ZIs not present, abbreviated as Z-th on-board distribution result

Expressing the vehicle-mounted distribution result in a set form as

In the present invention, the network information distribution means determining which of the roadside units to which the network information is distributed is.

Step 32: referring to FIG. 4B, the judgment is made one by one

And

whether the number of the roadside units in the set is more than 1 or not; if the number of roadside units is greater than 1, that is

If the vehicle-mounted nodes corresponding to the same network information of different roadside units are to be cleaned, executing step 33;

if the number of roadside units is less than or equal to 1, that is

Andabandoning the cleaning of the network information distributed by the roadside units;

in particular, the amount of the solvent to be used,

then believeInformation center IC abandon pair R³Assigned Rf²Cleaning;

the information center IC gives up the pair R⁵Assigned Rf³Cleaning;

the information center IC gives up the pair R^r-1Assigned Rf⁴Cleaning;

the information center IC gives up the pair R⁵Assigned Rf⁵Cleaning;

the information center IC gives up the pair R^rAssigned Rf^Z-1Cleaning;

indicating that no roadside units are assigned to Rf^ZTherefore, cleaning is not performed.

Step 33: for the

Cleaning vehicle-mounted nodes corresponding to the same network information of different roadside units;

referring to FIG. 3A, the first network information Rf is requested within the current memory period τ¹And will encounter a second roadside unit R in the next storage period tau +1²Has a first vehicle-mounted node V¹Abbreviated as R²－Rf¹-vehicle node

Namely, it is

The first network information Rf is requested within the current memory period tau¹And will encounter the fifth roadside unit R in the next storage period tau +1⁵Has a third vehicle node V³N-th vehicle-mounted node VⁿAbbreviated as R⁵－Rf¹-vehicle node

Namely, it is

The first network information Rf is requested within the current memory period tau¹And will encounter the R-th roadside unit R in the next storage period tau +1^rHas an nth vehicle-mounted node VⁿAbbreviated as R^r－Rf¹-vehicle node

Namely, it is${\mathrm{VC}}_{{\mathrm{<figure-callout\; label="R\; r\; Rf"\; filenames="HDA0000462146700000051.png"\; state="\{\{state\}\}">R</figure-callout>}}^r}^{{\mathrm{Rf}}^{}}=\left\{V^n\right\}.$

In the present invention, for the sake of general expression, any one of the network information Rf is requested within the current memory period τ^ZAnd will be in the next memory cycle τ +1Meet any roadside unit R^rIn-vehicle node of (2), abbreviated as R^r－Rf^Z-vehicle node

According to

And

the number of the medium elements is arranged in a descending order to obtain

The order of processing of the roadside units is thus in turn the fifth roadside unit R⁵A second roadside unit R²The R < th > roadside unit R^r；

Executing step 34 on the first ranked roadside unit, and then sequentially executing step 35 on the second ranked roadside unit to the last ranked roadside unit;

step 34: reserving a fifth roadside unit R⁵Assigned first network information Rf¹And recording the first vehicle-mounted intermediate distribution result

Then step 35 is executed;

step 35: for the second roadside unit R²To aim at

Of the first vehicle-mounted node V¹Judgment of

Whether it is an empty set, if it is an empty set, retaining the second oneRoadside unit R²Assigned first network information Rf¹And reassigns the first on-board intermediate distribution result

Otherwise, cleaning up the second roadside unit R²Assigned first network information Rf¹。

Due to the fact that

So that a second roadside unit R remains²Assigned first network information Rf¹And reassigns the first on-board intermediate distribution result

For the R roadside unit R^rTo aim at

N-th on-board node V in (1)ⁿJudgment ofIf the set is empty, the R-th roadside unit R is reserved^rAssigned first network information Rf¹And reassigns the first on-board intermediate distribution result

Otherwise, cleaning the R-th roadside unit R^rAssigned first network information Rf¹。

Due to the fact that

So that the R-th roadside unit R is cleaned^rAssigned first network information Rf¹I.e. removing edges from what is shown with reference to fig. 4B<a_i-1,b_j>The results shown in FIG. 4C were obtained.

After the network information allocated to the roadside unit is cleaned, step 36 is executed.

Step 36: the first vehicle-mounted intermediate distribution resultAssign a value to the first on-board distribution result

Namely, it is

And step 36, assigning the vehicle-mounted intermediate distribution result to a vehicle-mounted node corresponding to the vehicle-mounted intermediate distribution result, and finding out a corresponding roadside unit from the vehicle-mounted node.

Step 41 is executed after all of steps 33 to 36 are executed for all of the number of roadside units greater than 1.

In the invention, the third step is to sort the same network information in different roadside units according to the vehicle-mounted request identification information of the number of vehicle-mounted nodes which can be met by each roadside unit, and sequentially judge whether the network information is stored by each roadside unit redundantly, so that the redundant network information is cleared, the storage space of the roadside units is saved, and the theoretical optimal distribution scheme is better approached.

Step four: secondary distribution and updating bipartite graph vertex set

Step 41: referring to fig. 4B, the in-vehicle request identification information is removed

The numerical identification number associated with the left vertex of the connected edge, namely:

in which comprisesThenumber identification number 1;

thenumerical identification number 2 contained in (a);

thenumerical identification number 1 contained in (a);

the numerical identification number 3 contained therein;

thenumerical identification number 4 contained therein;

the numerical identification number 5 contained therein;

the numerical identification number Z-1 contained in (a);

thenumerical identification number 1 contained therein.

Obtaining the secondarily distributed vehicle-mounted request identification information

Wherein

In the invention, the vehicle-mounted node sends the required content to the roadside unit by the digital identification number, and the information center sends the content corresponding to the digital identification number to the roadside unit. Therefore, the identification number is deleted, and the network information of the content corresponding to the identification number can be printed.

Step 42: referring to FIG. 4D, the in-vehicle request identification information to be secondarily distributed

Element Z in (1) adds the label of the left vertex of the empty bipartite graph as a_iWherein a is_iThe recorded content is

A medium numeric identification number Z; step 43 is executed;

step 43: referring to FIG. 4C, the storage locations to which network information has been assigned are

Removing a full network storage location set <math> <mrow> <msup> <mi>UD</mi> <mi>RD</mi> </msup> <mo>=</mo> <mo>{</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>1</mn> </msup> </msup> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>2</mn> </msup> </msup> <mo>&cup;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mi>r</mi> </msup> </msup> <mo>}</mo> </mrow></math>The storage position of the network information is distributed to obtain a secondary scoreConfigured full-network storage location aggregation <math> <mrow> <mi>N</mi> <msup> <mi>UD</mi> <mi>RD</mi> </msup> <mo>=</mo> <mo>{</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>1</mn> </msup> </msup> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>4</mn> </msup> </msup> <mo>&cup;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mi>r</mi> </msup> </msup> <mo>}</mo> <mo>,</mo> </mrow></math>Wherein$U^{R^1}=\left\{u_1^{R^1}\right\},$$U^{R^4}=\left\{u_1^{R^4}\right\},$$U^{R^r}=\left\{u_2^{R^r}\right\}.$Step 44 is executed;

step 44: referring to FIG. 4D, the set of secondary allocated full network storage locations

Element (1) of

The identification number of the right vertex added into the bipartite graph is b₁,b₄,b_jWherein b is₁The recorded content is R¹First storage location of

b₄The recorded content is R⁴First storage location of

b_jThe recorded content is R^rSecond storage location ofStep 15 is performed.

In the invention, step four, the vehicle-mounted request identification information which is not responded and the vacant roadside unit storage positions are respectively added into the left vertex and the right vertex of the vacant bipartite graph by removing the vehicle-mounted request identification information which is responded and the occupied roadside unit storage positions, and the step 15 is returned to realize secondary distribution, thereby improving the utilization rate of the storage space and the data response rate.

Examples

Referring to fig. 3 and 3A, schematic driving diagrams of the vehicle-mounted node passing through the roadside unit are shown, and the corresponding relationship between the vehicle-mounted request identification information and the storage location of the roadside unit is shown in combination with fig. 4A, 4B, 4C and 4D. Comparative experiments were conducted on ONE (see document 1) simulation platform, and the experimental environment is as follows:

the CCR method is adopted to carry out simulation experiments, and a greedy method (literature 5) with priority on response time delay is selected as a comparison method in the simulation experiments and is marked as an ADG method. Two indicators, namely, data response rate (Availability) and average response delay (Access delay), were analyzed in the experiment. The experimental results are shown in fig. 5 and 6. In the figure, ". DELTA" denotes the ADG method and ". smallcircle" denotes the CCR method, i.e., the method disclosed in the present invention.

According to the comparison of the experimental results, the following conclusions can be obtained: the data response rate of the CCR method is obviously higher than that of the ADG method by about 10 percent; the average response time delay of the CCR method is slightly longer than that of the ADG method, and the average response time delay of the CCR method is only about 3s longer than that of the ADG method under the condition that the storage period is 50 s. In short, the CCR method of the present invention can significantly improve the data response rate, has no significant impact on the request response delay, can satisfy more data requests in the storage period, and achieves efficient data distributed storage, thereby ensuring the data service quality of the vehicle-mounted network.

In the present invention, the references cited are:

document 1. simulation platform ONE

The ONE simulator for DTN protocol evaluation；

The authors: ari Keranen, Jorg Ott, Teemu Karkkainen;

and (3) meeting: international Conference on Simulation Tools and Techniques (SIMUTOOL' 09);

time: 3 months and 2-6 days in 2009;

a place: roman, italy.

Document 2. random waypoint model

The node distribution of the random waypoint mobility model forwireless ad hoc networks；

The authors: christian Bettstetter, Giovanni Resta;

a periodical: IEEE Transactions on Mobile Computing;

time: in 2003;

page number:vol 2, stage 3, 257-.

Document 3 Normal distribution

3 rd edition, prosperity, thank forms, panzest and resold editions in 2001, probability theory and mathematical statistics, page 56.

Document 4 Poisson distribution

3 rd edition, prosperity, thank forms, panzest and resold editions in 12 months of 2001, probability theory and mathematical statistics, page 46.

Reference 5. comparison of ADG greedy methods

3 rd edition, 12 th month in 2009, written by wang xiao dong, "computer algorithm design and analysis", page 105.

Documents 6.V2V and V2I

Architecture and evaluation of a unified V2V and V2I communicationsystem based on cellular networks；

The authors: jose Santa, Antonio F.Gomez-Skrametaa, MarcSanchez-Artigas;

a periodical: computer Communications;

time: 2008;

page number: vol 31, No. 12, 2850 and 2861.

Claims (2)

1. A distributed storage method of a vehicle network based on bipartite graph, any one of the vehicle networks comprises a plurality of roadside units, a plurality of vehicle nodes and an information center IC; the communication between the vehicle-mounted nodes and the roadside units is V2I, the communication between the vehicle-mounted nodes is V2V, and the communication between the information center IC and the roadside units is an Internet network;

the roadside unit is expressed in a collective form as RD ═ R¹,R²,…,R^r}；

The vehicular node is expressed as VD (V) in a set form¹,V²,…,Vⁿ}；

The network information is expressed in a set form as <math> <mrow> <msup> <mi>F</mi> <mi>&tau;</mi> </msup> <mo>=</mo> <mfenced open='{' close='}'> <mtable> <mtr> <mtd> <msup> <mi>Rf</mi> <mn>1</mn> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mn>1</mn> </msub> <mo>,</mo> <mn>1</mn> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mn>2</mn> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mn>2</mn> </msub> <mo>,</mo> <mn>2</mn> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mn>3</mn> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mn>3</mn> </msub> <mo>,</mo> <mn>3</mn> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mn>4</mn> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mn>4</mn> </msub> <mo>,</mo> <mn>4</mn> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mn>5</mn> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mn>5</mn> </msub> <mo>,</mo> <mn>5</mn> <mo>)</mo> </mrow> </mtd> </mtr> <mtr> <mtd> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mrow> <mi>Z</mi> <mo>-</mo> <mn>1</mn> </mrow> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mrow> <mi>Z</mi> <mo>-</mo> <mn>1</mn> </mrow> </msub> <mo>,</mo> <mi>Z</mi> <mo>-</mo> <mn>1</mn> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>Rf</mi> <mi>Z</mi> </msup> <mrow> <mo>(</mo> <msub> <mi>content</mi> <mi>Z</mi> </msub> <mo>,</mo> <mi>Z</mi> <mo>)</mo> </mrow> <mo>,</mo> </mtd> </mtr> </mtable> </mfenced> <mo>;</mo> </mrow></math>

The distributed storage of the network information by the information center IC is characterized by comprising the following steps:

the method comprises the following steps: two-part diagram of structure

Step 11: setting an empty bipartite graph as G ═ X, Y, E, X denotes the left vertex, Y denotes the right vertex, and E denotes the edge; executing step 12;

step 12: store the current weekAcquired by information centre IC during period tau

The element in (b) is added to X of (X, Y, E) to obtain a bipartite graph G with a left vertex^XExecuting step 13;

the bipartite graph G with left vertices^XX ═ a is an element contained in the left vertex of (a)₁,a₂,a₃,a₄,a₅,a₆,a₇,…,a_i-1,a_i}, wherein:

a₁denotes the first left vertex, a₁The recorded content is

The numerical identification number 1 contained in (a);

a₂denotes the second left vertex, a₂The recorded content is

The numerical identification number 2 contained in (a);

a₃denotes the third left vertex, a₃The recorded content is

The numerical identification number 1 contained in (a);

a₄denotes the fourth left vertex, a₄The recorded content is

The numerical identification number 3 contained therein;

a₅denotes the fifth left vertex, a₅The recorded content is

The numerical identification number 4 contained therein;

a₆denotes the sixth left vertex, a₆Inside of recordContaining is

The numerical identification number 5 contained therein;

a₇denotes the seventh left vertex, a₇The recorded content is

The numerical identification number Z-1 contained in (a);

a_i-1denotes the i-1 th left vertex, a_i-1The recorded content is

The numerical identification number 1 contained in (a);

a_irepresents the last left vertex, a_iThe recorded content is

The numerical identification number Z contained in (a);

step 13: aiming at any roadside unit R in the vehicle-mounted network^rOne size is constructed as a storage capacity

Set of storage locations, asWherein,

represents R^rIs stored in the first storage location of the memory,

represents R^rIs stored in the first storage location of the memory,

represents R^rTo lastA storage location, performing step 14;

step 14: traverse all RD ═ R¹,R²,…,R^rObtaining a whole network storage position set by the roadside units in the <math> <mrow> <msup> <mi>UD</mi> <mi>RD</mi> </msup> <mo>=</mo> <mo>{</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>1</mn> </msup> </msup> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>2</mn> </msup> </msup> <mo>&cup;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mi>r</mi> </msup> </msup> <mo>}</mo> <mo>;</mo> </mrow></math>And will be <math> <mrow> <msup> <mi>UD</mi> <mi>RD</mi> </msup> <mo>=</mo> <mo>{</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>1</mn> </msup> </msup> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>2</mn> </msup> </msup> <mo>&cup;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mi>r</mi> </msup> </msup> <mo>}</mo> </mrow></math>Element(s) in (b) is added to bipartite graph G with left vertices^XIn Y of (3), a bipartite graph G having left and right vertex sets is obtained^X+YExecuting step 15;

the bipartite graph G with left and right vertex sets^X+YY ═ b₁,b₂,b₃,b₄,b₅,b₆,b₇,b₈,…,b_j-1,b_j}, wherein:

b₁representing the first right vertex, b₁The recorded content is R¹To (1) aA storage location

b₂Representing the second right vertex, b₂The recorded content is R²First storage location of

b₃Represents the third right vertex, b₃The recorded content is R³First storage location of

b₄Represents the fourth right vertex, b₄The recorded content is R⁴First storage location of

b₅Represents the fifth right vertex, b₅The recorded content is R⁵First storage location of

b₆Denotes the sixth right vertex, b₆The recorded content is R⁵Second storage location of

b₇Denotes the seventh right vertex, b₇The recorded content is R⁵Third storage location of

b₈Denotes the eighth right vertex, b₈The recorded content is R^r-1First storage location of

b_j-1Represents the j-1 th right vertex, b_j-1The recorded content is R^rFirst storage location of

b_jRepresenting the last right vertex, b_jThe recorded content is R^rSecond storage location of

Step 15: matching conditions with verticesAnd is

And is

To judge the bipartite graph G with left and right vertex sets^X+YWhether X and Y in (1) are connected with each other is judged, so that a bipartite graph with vertexes and edges is constructedExecuting step 21;

a₁and b₂Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₁,b₂>；

a₂And b₃Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₂,b₃>；a₂And b₄Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₂,b₄>；

a₃And b₅Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₃,b₅>；a₃And b₆Satisfy the vertex matching conditionAnd is

And isThen at G^X+YThe edge set E of (1) adds edges<a₃,b₆>；a₃And b₇Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₃,b₇>；

a₄And b₅Satisfy the vertex matching condition

And isAnd is

Then at G^X+YThe edge set E of (1) adds edges<a₄,b₅>；a₄And b₆Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₄,b₆>；a₄And b₇Satisfy the vertex matching conditionAnd is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₄,b₇>；

a₅And b₈Satisfy the vertex matching condition

And is

And is

Then at G^X+YAdding edges a5 and b8 to the edge set E; a is₅And b_j-1Satisfy the vertex matching condition

And is

And isThen at G^X+YThe edge set E of (1) adds edges<a₅,b_j-1>；a₅And b_jSatisfy the vertex matching condition

And isAnd isThen at G^X+YThe edge set E of (1) adds edges<a₅,b_j>；

a₆And b₅Satisfy the vertex matching condition

And isAnd isThen at G^X+YThe edge set E of (1) adds edges<a₆,b₅>；a₆And b₆Satisfy the vertex matching conditionAnd is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₆,b₆>；a₆And b₇Satisfy the vertex matching conditionAnd is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₆,b₇>；

a₇And b₅Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₇,b₅>；a₇And b₆Satisfy the vertex matching conditionAnd is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₇,b₆>；a₇And b₇Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₇,b₇>；a₇And b_j-1Satisfy the vertex matching condition

And is

And isThen at G^X+YThe edge set E of (1) adds edges<a₇,b_j-1>；a₇And b_jSatisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a₇,b_j>；

a_i-1And b₅Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i-1,b₅>；a_i-1And b₆Satisfy the vertex matching condition

And isAnd is

Then at G^X+YThe edge set E of (1) adds edges<a_i-1,b₆>；a_i-1And b₇Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i-1,b₇>；a_i-1And b_j-1Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i-1,b_j-1>；a_i-1And b_jSatisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i-1,b_j>；

a_iAnd b₅Satisfy the vertex matching conditionAnd is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i,b₅>；a_iAnd b₆Satisfy the vertex matching conditionAnd isAnd is

Then at G^X+YThe edge set E of (1) adds edges<a_i,b₆>；a_iAnd b₇Satisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i,b₇>；a_iAnd b_j-1Satisfy the vertex matching condition

And is

And isThen at G^X+YThe edge set E of (1) adds edges<a_i,b_j-1>；a_iAnd b_jSatisfy the vertex matching condition

And is

And is

Then at G^X+YThe edge set E of (1) adds edges<a_i,b_j>；

The edge in the statistical edge set E comprises<a₁,b₂>、<a₂,b₃>、<a₂,b₄>、<a₃,b₅>、<a₃,b₆>、<a₃,b₇>、<a₄,b₅>、<a₄,b₆>、<a₄,b₇>、<a₅,b₈>、<a₅,b_j-1>、<a₅,b_j>、<a₆,b₅>、<a₆,b₆>、<a₆,b₇>、<a₇,b₅>、<a₇,b₆>、<a₇,b₇>、<a₇,b_j-1>、<a₇,b_j>、<a_i-1,b₅>、<a_i-1,b₆>、<a_i-1,b₇>、<a_i-1,b_j-1>、<a_i-1,b_j>、<a_i,b₅>、<a_i,b₆>、<a_i,b₇>、<a_i,b_j-1>And<a_i,b_j>；

step two: finding a bipartite graph maximum matching subgraph

Step (ii) of21: if there are vertices and edges

If the edge set E is not empty, step 22 is executed;

if there are vertices and edges

If the edge set E is empty, ending the distributed storage and outputting a vehicle-mounted distribution result DI;

step 22: applying the Hungarian algorithm from bipartite graphs with vertices and edges

Obtaining maximum matching subgraph GB ═<(X,Y),EB>Where EB is a bipartite graph with vertices and edgesA subset of the edge set E (EB is simply referred to as an edge subset); EB ═ tone<γ,β>I γ ∈ X, β ∈ Y }, where γ denotes the maximum matching subgraph GB ═ Y }<(X,Y),EB>The left vertex of any one edge in the edge set EB, and beta represents the maximum matching subgraph GB ═<(X,Y),EB>The right vertex of any one edge in the edge set EB; step 31 is executed;

the edges in the edge subset EB comprise<a₁,b₂>、<a₂,b₃>、<a₃,b₅>、<a₄,b₆>、<a₅,b₈>、<a₆,b₇>、<a₇,b_j-1>And<a_i-1,b_j>(ii) a Gamma includes an edge<a₁,b₂>A in (a)₁Edge of<a₂,b₃>A in (a)₂Edge of<a₃,b₅>A in (a)₃Edge of<a₄,b₆>A in (a)₄Edge of<a₅,b₈>A in (a)₅Edge of<a₆,b₇>A in (a)₆Edge of<a₇,b_j-1>A in (a)₇And edge<a_i-1,b_j>A in (a)_i-1(ii) a Then beta includes an edge<a₁,b₂>B in (1)₂Edge of<a₂,b₃>B in (1)₃Edge of<a₃,b₅>B in (1)₅Edge of<a₄,b₆>B in (1)₆Edge of<a₅,b₈>B in (1)₈Edge of<a₆,b₇>B in (1)₇Edge of<a₇,b_j-1>B in (1)_j-1And edge<a_i-1,b_j>B in (1)_j；

Step three: distributing and cleaning network information

Step 31: after the network information distribution is completed, the vehicle-mounted distribution result is obtained asStep 32 is executed;

will edge<a₁,b₂>First left vertex a in (1)₁Corresponding Rf¹Assigned to the second right vertex b₂Corresponding R²Performing the following steps;

will edge<a₂,b₃>Second left vertex a in (1)₂Corresponding Rf²Is assigned to the third right vertex b₃Corresponding R³Performing the following steps;

will edge<a₃,b₅>Third left vertex a in (1)₃Corresponding Rf¹Assigned to the fifth right vertex b₅Corresponding R⁵Performing the following steps;

will edge<a₄,b₆>The fourth left vertex a in₄Corresponding Rf³Assigned to the sixth right vertex b₆Corresponding R⁵Performing the following steps;

will edge<a₅,b₈>The fifth left vertex a in₅Corresponding Rf⁴Is assigned to the eighth right vertex b₈Corresponding R^r-1Performing the following steps;

a side of a₆,b₇>Sixth of (1)Left vertex a₆Corresponding Rf⁵Assigned to the seventh right vertex b₇Corresponding R⁵Performing the following steps;

will edge<a₇,b_j-1>Seventh left vertex a in₇Corresponding Rf^Z-1Is distributed to the j-1 th right vertex b_j-1Corresponding R^rPerforming the following steps;

will edge<a_i-1,b_j>The ith-1 left vertex a in_i-1Corresponding Rf¹Is assigned to the jth right vertex b_jCorresponding R^rPerforming the following steps;

assigned first network information Rf¹The roadside unit has a second roadside unit R²The fifth roadside unit R⁵The R < th > roadside unit R^rFirst on-board distribution result

Second network information Rf is assigned²The roadside unit has a third roadside unit R³Simply called second on-board distribution result$d^{{\mathrm{Rf}}^2}=\left\{R^3\right\};$

Third network information Rf is assigned³The roadside unit has a fifth roadside unit R⁵Short third on-board distribution results$d^{{\mathrm{Rf}}^3}=\left\{R^5\right\};$

Fourth network information Rf is assigned⁴The roadside unit has the R-1 th roadside unit R^r-1Fourth on-board distribution result$d^{{\mathrm{Rf}}^2}=\left\{R^{r-1}\right\};$

Fifth network information Rf is assigned⁵The roadside unit has a fifth roadside unit R⁵Fifth vehicle distribution result for short$d^{{\mathrm{Rf}}^5}=\left\{R^5\right\};$

Z-1 th network information Rf is assigned^Z-1The roadside unit has an R-th roadside unit R^rZ-1 th vehicle distribution result

Z-th network information Rf is assigned^ZIs not present, abbreviated as Z-th on-board distribution result

Expressing the vehicle-mounted distribution result in a set form as

Step 32: judge one by one

Andwhether the number of the roadside units in the set is more than 1 or not; if the number of roadside units is greater than 1, that is

Step 33 is executed;

if the number of roadside units is less than or equal to 1, that is

And

abandoning the cleaning of the network information distributed by the roadside units;

in particular, the amount of the solvent to be used,the information center IC gives up the pair R³Assigned Rf²Cleaning;

the information center IC gives up the pair R⁵Assigned Rf³Cleaning;

the information center IC gives up the pair R^r-1Assigned Rf⁴Cleaning;

the information center IC gives up the pair R⁵Assigned Rf⁵Cleaning;

the information center IC gives up the pair R^rAssigned Rf^Z-1Cleaning;

indicating that no roadside units are assigned to Rf^ZTherefore, cleaning is not carried out;

step 33: for the$d^{{\mathrm{Rf}}^1}=\{R^2,R^5,R^r\};$

The first network information Rf is requested within the current memory period tau¹And will encounter a second roadside unit R in the next storage period tau +1²Has a first vehicle-mounted node V¹Abbreviated as R²－Rf¹-vehicle node

Namely, it is${\mathrm{VC}}_{R^2}^{{\mathrm{Rf}}^1}=\left\{V^1\right\};$

The first network information Rf is requested within the current memory period tau¹And will encounter the fifth roadside unit R in the next storage period tau +1⁵Has a third vehicle node V³N-th vehicle-mounted node VⁿAbbreviated as R⁵－Rf¹-vehicle node

Namely, it is

The first network information Rf is requested within the current memory period tau¹And will encounter the R-th roadside unit R in the next storage period tau +1^rHas an nth vehicle-mounted node VⁿAbbreviated as R^r－Rf¹-vehicle node

Namely, it is${\mathrm{VC}}_{R^r}^{{\mathrm{Rf}}^1}=\left\{V^n\right\};$

According to

Andthe number of the medium elements is arranged in a descending order, and the processing order of the obtained roadside units is the fifth roadside unit R in sequence⁵A second roadside unit R²The R < th > roadside unit R^r；

To the fifth roadside unit R which is positioned at the head after sequencing⁵Step 34 is executed, the second roadside unit R located after the head²And the R-th roadside unit R^rRespectively executing the steps 35 in sequence;

step 34: reserving a fifth roadside unit R⁵Assigned first network information Rf¹And recording the first vehicle-mounted intermediate distribution result

Then step 35 is executed;

step 35: for the second roadside unit R²To aim at

Of the first vehicle-mounted node V¹Judgment of

If it is an empty set, then the second roadside unit R is reserved²Assigned first network information Rf¹And reassigns the first on-board intermediate distribution result

Otherwise, cleaning up the second roadside unit R²Assigned first network information Rf¹；

Due to the fact that

So that a second roadside unit R remains²Assigned first network information Rf¹And reassigns the first on-board intermediate distribution result

For the R roadside unit R^rTo aim at

N-th on-board node V in (1)ⁿJudgment of

If the set is empty, the R-th roadside unit R is reserved^rAssigned first network information Rf¹And reassigns the first on-board intermediate distribution result

Otherwise, cleaning the R-th roadside unit R^rAssigned first network information Rf¹；

Due to the fact that

So that the R-th roadside unit R is cleaned^rAssigned first network information Rf¹；

After finishing cleaning the network information distributed by the roadside unit, executing step 36;

step 36: the first vehicle-mounted intermediate distribution result

Assign a value to the first on-board distribution result

Namely, it is$d^{{\mathrm{Rf}}^1}=\{R^5,R^2\};$

Executing step 41 for all the road edge units with the number more than 1 after steps 33 to 36 are executed;

step four: secondary distribution and updating bipartite graph vertex set

Step 41: removing vehicle-mounted request identification information

The numerical identification number associated with the left vertex of the connected edge, namely:

the numerical identification number 1 contained in (a);

the numerical identification number 2 contained in (a);

the numerical identification number 1 contained in (a);

in which comprisesThe number identification number 3;

the numerical identification number 4 contained therein;

the numerical identification number 5 contained therein;

the numerical identification number Z-1 contained in (a);

the numerical identification number 1 contained in (a);

obtaining the secondarily distributed vehicle-mounted request identification information

Wherein

Step 42: secondarily distributed vehicle-mounted request identification information

Element Z in (1) adds the label of the left vertex of the empty bipartite graph as a_iWherein a is_iThe recorded content is

A medium numeric identification number Z; step 43 is executed;

step 43: the storage position allocated with the network information is provided with

Removing a full network storage location set <math> <mrow> <msup> <mi>UD</mi> <mi>RD</mi> </msup> <mo>=</mo> <mo>{</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>1</mn> </msup> </msup> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mn>2</mn> </msup> </msup> <mo>&cup;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&CenterDot;</mo> <mo>&cup;</mo> <msup> <mi>U</mi> <msup> <mi>R</mi> <mi>r</mi> </msup> </msup> <mo>}</mo> </mrow></math>The storage position with the network information is distributed in the storage position distribution table to obtain a secondary distribution whole network storage position set

Wherein$U^{R^1}=\left\{u_1^{R^1}\right\},$$U^{R^4}=\left\{u_1^{R^4}\right\},$$U^{R^r}=\left\{u_2^{R^r}\right\};$Step 44 is executed;

step 44: aggregating secondary allocated full-network storage locations

Element (1) of

The identification number of the right vertex added into the bipartite graph is b₁,b₄,b_jWherein b is₁The recorded content is R¹First storage location of

b₄The recorded content is R⁴First storage location of

b_jThe recorded content is R^rSecond storage location ofStep 15 is performed.

2. The bipartite graph-based in-vehicle network distributed storage method according to claim 1, wherein: the data response rate is improved by 10%.

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