CN105791408A - A method and system for constructing a P2P network - Google Patents

Abstract

The invention discloses a construction method and system of a P2P network. The method includes: numbering all network nodes; constructing a loop passing through all network nodes, and the two network nodes connected in the loop are located in different domains; traversing all network nodes, and randomly selecting a target network node: if the current If the traversed network node and the target network node are in different domains, a directed edge is added between the current network node and the target network node. The P2P network constructed by the invention has strong connectivity, cross-region characteristics and robustness.

Description

A method and system for constructing a P2P network

technical field

The invention relates to the field of network technology, in particular to a method and system for constructing a P2P network.

Background technique

P2P (peer-to-peer, peer-to-peer) network is widely used in communication systems because of its strong robustness. However, from the perspective of tracking, the existing P2P network has the following defects:

First of all, communication is local: communication tends to occur between nodes in the same domain. Once the source node of a certain communication is exposed, a third party can easily track the corresponding destination node. In this paper, "domain" refers to a logical unit for dividing the Internet, which may be a region (country/province/city/...), autonomous domain, Internet service provider, etc. Each domain has independent Internet supervision rights, and monitoring multiple domains requires inter-domain cooperation. Secondly, the source of communication is easily exposed: nodes use their real identities to communicate, and once the destination node of a certain communication is exposed, the corresponding source node will also be exposed.

Since the complex communication mechanism of the P2P network often leads to a large number of frequent communications within the network, the above-mentioned defects are likely to expose the P2P topology characteristics of the communication subgraph in each domain of the existing P2P network. At present, there is still a lack of P2P networks that can effectively resist tracking. Therefore, how to ensure that P2P networks have strong anti-tracking properties is a technical problem that needs to be solved urgently in the field of network technology.

Contents of the invention

In order to solve the problem of poor anti-tracking capability of the P2P network in the prior art, the present invention proposes a new method and system for constructing the P2P network.

In order to solve the above technical problems, the present invention is achieved through the following technical solutions.

According to one aspect of the present invention, a method for constructing a P2P network is provided, including:

Number all network nodes;

Construct a loop passing through all network nodes, and the two network nodes connected in the loop are located in different domains;

Traverse all network nodes and randomly select a target network node: if the currently traversed network node and the target network node are in different domains, add a directed edge between the current network node and the target network node .

Further, the numbering of all network nodes includes:

Count network nodes and classify all network nodes by domain;

Randomly select a network node from the domain with the largest number of network nodes, randomly select a network node from other domains, and repeat this step until all network nodes are selected;

If the remaining network nodes are in the same domain, randomly select network nodes in this domain until all network nodes are selected;

After all the network nodes are selected, all the network nodes are numbered sequentially according to the order in which they were selected.

Further, constructing a loop passing through all network nodes, and the two network nodes connected in the loop are located in different domains, including:

Starting from any node, construct a loop connecting all network nodes through directed edges;

Reversely traversing the loop: if the source node and the target node of a directed edge in the loop are in the same domain, then delete the directed edge;

A network node is randomly selected from other domains, and directed edges are added between the source node and the network node, and between the network node and the target node.

Further, if the currently traversed network node and the target network node are located in different domains, adding a directed edge between the current network node and the target network node includes:

Taking the current network node as a source node, randomly selecting a preset number of target nodes from other network nodes in different domains, and adding a directed edge between the source node and the target node.

According to another aspect of the present invention, a system for constructing a P2P network is provided, including:

Node sorting subsystem, used to number all network nodes;

A loop construction subsystem, configured to construct a loop passing through all network nodes, and the two network nodes connected in the loop are located in different domains;

The random edge adding subsystem is used to traverse all network nodes and randomly select a target network node: if the currently traversed network node and the target network node are located in different domains, then the current network node and the target network node Add directed edges between nodes.

Further, the node sorting subsystem includes:

A statistical unit is used to count network nodes and classify all network nodes by domain;

The selection unit is used to randomly select a network node from the domain with the largest number of network nodes, randomly select a network node from other domains, and repeat this step until all network nodes are selected; if the remaining network nodes are in the same domain, Then randomly select network nodes in this domain until all network nodes are selected;

The numbering unit is used to sequentially number all network nodes according to the order in which they were selected after all network nodes are selected.

Further, the circuit construction subsystem includes:

The circuit construction unit is used to start from any node and construct a circuit connecting all network nodes through directed edges;

A deletion unit for traversing the loop in reverse: if the source node and the target node of a directed edge in the loop are in the same domain, delete the directed edge;

The edge adding unit is configured to randomly select a network node from other domains, and add directed edges between the source node and the network node, and between the network node and the target node.

Further, the random edge adding subsystem is specifically used for:

Taking the current network node as a source node, randomly selecting a preset number of target nodes from other network nodes in different domains, and adding a directed edge between the source node and the target node.

The beneficial effects of the present invention are as follows:

In the P2P network construction method and system provided by the present invention, messages injected from any node can cover all nodes, so that the entire network has strong connectivity; the source node and target node of any edge belong to different domains , which has cross-region characteristics; after deleting some nodes and their connected edges, the remaining subgraph still has strong robustness.

Description of drawings

Fig. 1 is a flow chart of a P2P network construction method in an embodiment of the present invention;

Fig. 2 is a flowchart of node sorting in an embodiment of the present invention;

Fig. 3 is a flowchart of loop construction in an embodiment of the present invention;

Fig. 4 is the directed graph of the P2P network constructed in an embodiment of the present invention;

Fig. 5 is a flowchart of random edge addition in an embodiment of the present invention;

Fig. 6 is a comparison chart of anti-tracking performance between the P2P network and the TDL-4 network constructed in the embodiment of the present invention;

Fig. 7 is the robustness-to-contrast diagram of the P2P network constructed in the embodiment of the present invention and the TDL-4 network;

Fig. 8 is a structural block diagram of a P2P network construction system in an embodiment of the present invention.

detailed description

In order to solve the problem of poor anti-tracking ability of the network in the prior art, the present invention provides a method and system for constructing a P2P network. The present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Referring to Fig. 1, the embodiment of the present invention provides a kind of construction method of P2P network, specifically comprises the following steps:

Step 1, numbering all network nodes;

Step 2, construct a loop passing through all network nodes, and the two network nodes connected in the loop are located in different domains;

Step 3, traverse all network nodes, and randomly select the target network node: if the currently traversed network node and the target network node are in different domains, add a directed edge between the current network node and the target network node.

In the construction method of the P2P network provided in the present invention, after the message is injected from any network node, it can cover all nodes, so that the entire network has strong connectivity; two network nodes on any edge in the network belong to Different domains have cross-region characteristics; after deleting some nodes and their connected edges, the remaining network subgraphs still have strong robustness.

The specific implementation process of each step of the present invention will be introduced in detail below.

Firstly, the process of node sorting is introduced: numbering all network nodes. Referring to Figure 2, it specifically includes the following steps:

Step 101, counting network nodes, and classifying all network nodes by domain;

Step 102, randomly select a network node from the domain with the largest number of network nodes, randomly select a network node from other domains, repeat this step until all network nodes are selected; if the remaining network nodes are in the same domain, then in Randomly select network nodes in this domain until all network nodes are selected;

Step 103, after all the nodes are selected, number all the network nodes in sequence according to the selected order, and the numbers are: v ₀ , v ₁ , . . . , v _N-1 .

Next, introduce the process of circuit construction: construct a circuit passing through all network nodes, and the two network nodes connected in the circuit are located in different domains. See Figure 3, including:

Step 201, starting from any node, constructing a loop connecting all network nodes through directed edges. In one embodiment of the present invention, starting from the network node with the smallest number, the loops are constructed by connecting each node sequentially in ascending order of numbers. Wherein, the formed circuit is a directed ring passing through each node at least once. For example, V ₀ -V ₁ -V ₂ -V ₃ -V ₀ is a directed ring that passes each node once, and it can also be V ₀ -V ₃ -V ₁ -V ₂ -V ₃ -V ₀ . The node V ₃ in the directed ring has passed through twice, and the other points have passed through once.

Step 202, traversing the loop in reverse: if the source node and the target node of a directed edge in the loop are in the same domain, delete the directed edge.

Referring to FIG. 4 , this network is described by a directed graph G(V,E) in the embodiment of the present invention. Among them, V represents the network node set (v ₀ , v ₁ ,...,v _N-1 ), and E represents the connection set, that is, the set between two network node edges. Graph G contains N network nodes distributed in M domains (N>>M>>1). Each network node represents a host; v _i .m represents the domain number of node v _i , which is used to identify the domain to which the host corresponding to node v _i belongs; the dashed edge <v _i , v _j > represents the connection relationship v _i → v _j , where, v _i is called the source node, v _j is called the target node, and v _i uses a forged identity to send messages to v _j .

Specifically, after the directed ring is constructed, the co-domain edges in the directed ring are deleted. In the embodiment of the present invention, starting from v _N-1 , reversely traverse the directed ring, if there is: Then delete the edge <v _i , v _j >; when the source node and the target node are from the same domain, delete the edge between the source node and the target node. Since co-domain edges would destroy the cross-domain properties of the network, they must be removed from the graph.

Step 203, randomly select a network node from other domains, and add directed edges between the source node and the network node, and between the network node and the target node.

In order to ensure the cross-domain characteristics of the network, after the co-domain edge <v _i , v _j > is deleted, it is necessary to randomly select a node v _k from a domain different from the source node (satisfying the condition: v _k .m≠v _i .m ), then add two edges in the network: <v _i , v _k > and <v _k , v _j >. In the embodiment of the present invention, by deleting co-domain edges and performing cross-domain random reconnection, the strong connectivity and cross-domain characteristics of the loop are guaranteed.

Finally, the process of randomly adding edges is introduced: traverse all network nodes and randomly select the target network node: if the currently traversed network node and the target network node are in different domains, add a link between the current network node and the target network node to the side.

Specifically, when adding edges randomly, it is necessary to use the current network node as the source node, and randomly select a preset number of target nodes from other network nodes in different domains, and add a directed edge between the source node and the target node . Fig. 5 is the flow chart of randomly adding edges in the embodiment of the present invention, and its specific implementation steps are as follows:

Step 301, preset edge adding parameter K, and set initial value k=0;

Step 302, traversing all network nodes;

Step 303, take the current node as the source node, and randomly select a target node from the remaining nodes, if the target node and the source node are from different domains, add an edge, k=k+1; if k≤K, continue to select Target node, and add edge;

Step 304, when all network nodes are added with edges, the method ends.

The experimental results show that compared with the disclosed related technologies, the method and system disclosed in the present invention mainly have the following positive effects:

(1) Strong tracking resistance: Fig. 6 shows a comparison chart of tracking resistance between the P2P network (named CRA network) constructed by the present invention and the TDL-4 network in the prior art. The abscissa (#ofrealms) represents the domain number, and all 17 countries in Figure 6 ("Others" is regarded as a special country) are numbered from 1 in order of host occupancy from low to high. The vertical axis (α) represents the tracking resistance, that is, when the defender has the monitoring right of the first i domains, the number of hosts that may be tracked accounts for the percentage of the total. The smaller α is, the stronger the tracking resistance is. The Total curve represents the cumulative occupancy of hosts on the domain. It can be seen from Figure 7 that the TDL-4 curve is closer to the Total curve than the CRA curve. Therefore, CRA is more resistant to tracking than TDL-4.

(2) Strong robustness: Figure 7 shows the robustness comparison between CRA and TDL-4. The abscissa (p) represents the removal rate, that is, the p part of nodes with the highest degree of removal from the topology graph. The ordinate represents the robustness (β), which is the ratio of the number of nodes contained in the largest connected subgraph to the total number of nodes contained in the remaining subgraph after the p part of nodes with the highest degree is removed. The larger β is, the stronger the robustness is. It can be seen from Figure 8 that CRA is more robust than TDL-4.

Referring to Figure 8, the embodiment of the present invention also provides a P2P network construction system, including:

Node sorting subsystem, used to number all network nodes;

The circuit construction subsystem is used to construct a circuit passing through all network nodes, and the two network nodes connected in the circuit are located in different domains;

The random edge addition subsystem is used to traverse all network nodes and randomly select the target network node: if the currently traversed network node and the target network node are in different domains, add a directed edge between the current network node and the target network node. side.

Further, the node sorting subsystem includes:

A statistical unit is used to count network nodes and classify all network nodes by domain;

The selection unit is used to randomly select a network node from the domain with the largest number of network nodes, randomly select a network node from other domains, and repeat this step until all network nodes are selected; if the remaining network nodes are in the same domain, Then randomly select network nodes in this domain until all network nodes are selected;

The numbering unit is used to sequentially number all network nodes according to the order in which they were selected after all network nodes are selected.

Further, the circuit construction subsystem includes:

The circuit construction unit is used to start from any node and construct a circuit connecting all network nodes through directed edges;

Delete unit, used to traverse the loop in reverse: if the source node and target node of a directed edge in the loop are in the same domain, the directed edge will be deleted;

The edge adding unit is used to randomly select a network node from other domains, and add directed edges between the source node and the network node, and between the network node and the target node.

Further, the random edge addition subsystem is specifically used for:

Take the current network node as the source node, randomly select a preset number of target nodes from other network nodes in different domains, and add directed edges between the source node and the target node.

Since the functions implemented by the device in this embodiment basically correspond to the aforementioned methods in FIGS. 1-5 , for details not described in this embodiment, you can refer to the relevant descriptions in the aforementioned embodiments, and details are not repeated here.

Although preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, and therefore, the scope of the present invention should not be limited to the above-described embodiments.

Claims (8)

1. the construction method of a P2P network, it is characterised in that including:

All of network node is numbered；

Build a loop through all-network node, and two network nodes being connected in described loop are positioned at different territories；

Travel through all of network node, and randomly choose target network node: if the network node of current traversal is positioned at different territories from described target network node, then between described current network node and described target network node, add a directed edge.

2. the method for claim 1, it is characterised in that described all of network node is numbered includes:

Statistics network node, and all-network node is sorted out by territory；

One network node of random choose from the territory that number of network node is maximum, from other territories, one network node of random choose, repeats this step, until all-network node is selected complete；

If remaining network node is positioned at same territory, then random choose network node in this domain, until all-network node is selected complete；

After all-network node is selected, all-network node is sequentially numbered according to selected sequencing.

3. the method for claim 1, it is characterised in that one loop through all-network node of described structure, and in described loop be connected two network nodes be positioned at different territories, including:

From arbitrary node, built the loop connecting all-network node by directed edge；

The described loop of reverse traversal: if the source node of a directed edge and destination node are positioned at same territory in described loop, described directed edge is deleted；

From other territories, randomly select a network node, between described source node and described network node, described network node and described destination node, add directed edge.

4. the method for claim 1, it is characterised in that if the network node of described current traversal is positioned at different territories from described target network node, then add directed edge between described current network node and described target network node, including:

With current network node for source node, and other network nodes of never same area randomly choose the destination node of predetermined number, and between described source node and described destination node, add directed edge.

5. the constructing system of a P2P network, it is characterised in that including:

Node sequencing subsystem, for being numbered all of network node；

Loop builds subsystem, and for building a loop through all-network node, and two network nodes being connected in described loop are positioned at different territories；

Random edged subsystem, for traveling through all of network node, and randomly choose target network node: if the network node of current traversal is positioned at different territories from described target network node, then between described current network node and described target network node, add directed edge.

6. system as claimed in claim 5, it is characterised in that described node sequencing subsystem, including:

Statistic unit, for statistics network node, and sorts out all-network node by territory；

Module of selection, for one network node of random choose the territory maximum from number of network node, from other territories, one network node of random choose, repeats this step, until all-network node is selected complete；If remaining network node is same territory, then random choose network node in this domain, until all-network node is selected complete；

Numbered cell, for, after all-network node is selected, being sequentially numbered all-network node according to selected sequencing.

7. system as claimed in claim 5, it is characterised in that described loop builds subsystem and includes:

Loop construction unit, for from arbitrary node, building the loop connecting all-network node by directed edge；

Delete unit, for the described loop of reverse traversal: if the source node of a directed edge and destination node are positioned at same territory in described loop, deleted by described directed edge；

Edged unit, for randomly selecting a network node from other territories, adds directed edge between described source node and described network node, described network node and described destination node.

8. system as claimed in claim 5, it is characterised in that described random edged subsystem specifically for:

With current network node for source node, and other network nodes of never same area randomly choose the destination node of predetermined number, and between described source node and described destination node, add directed edge.