CN102594926B - Heterogeneous wireless peer-to-peer (P2P) network file sharing system and file transmission acceleration method - Google Patents

Abstract

The invention discloses a heterogeneous wireless P2P network file sharing system and an accelerated file transmission method. In the heterogeneous wireless converged network access environment, based on the extended P2P-Bittorrent protocol, the characteristics of the converged network are comprehensively considered to access the network Type, terminal node download rate, network distance between nodes and round-trip time and other factors, use the optimization theory in engineering to select seed nodes, and provide an acceleration method for terminal file sharing services. Due to the proper selection of seed nodes, the large data flow and heavy load network services are transferred to relatively idle networks, which realizes the load balancing of the entire network structure and optimizes the resource efficiency of heterogeneous fusion multi-networks.

Description

Heterogeneous wireless P2P network file sharing system and accelerated file transfer method

technical field

The present invention relates to a file sharing system and an accelerated file transmission method for multi-mode wireless terminals in a plurality of heterogeneous fusion network coverage environments, especially to a P2P-Bittorrent protocol, applicable to WLAN, 3G/LTE, Ad hoc networks and future various A novel wireless access network file sharing system and an accelerated file transfer method.

Background technique

In recent years, wireless mobile access technology has developed rapidly. Wireless local area network (WLAN) represented by 802.11 series, 3G/HSPA/LTE represented by CDMA2000, WCDMA and TD-SCDMA have been applied on a large scale, and self-organizing network Ad hoc With the continuous research and development of technology, the future mobile Internet will be an open heterogeneous wireless network system with multiple access networks coexisting.

The main business based on the mobile Internet has shifted from voice services to various data services, and file sharing, as a basic application of distributed systems, has been widely used in the Internet. The P2P technology originated from the Internet can just adapt to the characteristics of self-organization, diverse network topologies, and dynamic access terminals of the mobile Internet. Therefore, P2P applications based on mobile Internet services are also key technologies for data services under the mobile Internet.

The characteristics of data services under the mobile Internet include fast update of data content, wide distribution of data size, strong dynamics of user groups, frequent switching, and in the heterogeneous wireless multi-network convergence environment, due to the inclusion of multiple networks, the overlap between networks There are also various ways. In order to make the file sharing model applicable to any number of overlapping application scenarios in any way, the existing P2P file sharing system based on the Bittorrent protocol is due to its good scalability, fast file distribution, and node The balance between upload and download is referenced and adopted by many mobile P2P applications.

Traditional Bittorrent shares files through torrent files, which includes 4 components: Tracker server, torrent files, seed node seed with complete backup of shared files, and peer nodes that request to obtain files. Among them, it is very critical for the Tracker server to select an effective peer node set, especially in the mobile Internet under the mobile terminal access status dynamic join and exit, in order to maintain the status information of dynamic nodes, it will increase the burden on the Tracker server; The network topology is grouped by logical location, and the nodes in the group are preferentially selected. However, since the node network topology does not correspond to the physical location topology, if the nodes with the closest distance in the network topology are far apart in the actual location, the stability of the node will also be affected. At the same time, to increase the data transmission burden of the mobile core network, none of the above methods can solve the effective screening of nodes by Tracker, so that the sharing rate can be increased.

How to improve the file sharing rate in the above application environment with diverse networks and strong node dynamics, and for the download quality of terminal nodes, consider factors such as node download rate, neighbor node upload rate, network distance, access network type, round-trip time RTT, etc. Considering the compromise, it is very necessary to improve the file sharing performance in the whole heterogeneous converged multi-network environment, and it can be widely used in other enhanced data services.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the defects and deficiencies of the technical methods described above, and provide a heterogeneous wireless P2P network file sharing system and accelerated file sharing system based on the P2P-Bittorrent protocol in the heterogeneous wireless converged network access environment. transfer method.

In order to solve the above-mentioned technical problems, the present invention provides a heterogeneous wireless P2P network file sharing system, which is characterized in that it includes a Tracker server, a mobile proxy node, and a general mobile terminal;

Described Tracker server comprises interactive control module, Peer management module, optimization selection module and network analysis module;

The interaction control module: used for signaling interaction with the mobile proxy node and the general mobile node, the signaling interaction is based on the extended Bittorrent protocol; the extended Bittorrent protocol includes an extension field nettype, which is described as "Client access network type", rttime, which is described as "the round-trip time RTT from the client to the mobile agent node";

The Peer management module: used to realize the discovery, statistics and recording of mobile proxy nodes and general mobile nodes in the entire distributed P2P network, establish a unified real-time Peer information management library for the entire network, and perform seed node selection as an optimization selection module Peer information source;

Optimization selection module: used to select the seed node list of the node most suitable for the current request file sharing service, to maximize the file sharing speed;

Described network analysis module: be used for regularly obtaining the report of mobile agent node to respective network position, specifically comprise IP address, network description, specific geographical position description information; Regularly obtain the IP address that general mobile node reports, gateway address information, and network The RTT value between the mobile agent nodes in the interior; and for the above information, analyze the logical topology structure of each distributed P2P network, and count the end-to-end RTT value of the mobile node, which is convenient for the optimization selection module to calculate the optimal value of each reference seed node;

The mobile proxy unit includes a location management module and an access control module;

Described location management module: the mobile agent unit, as the central node of the network cluster, regularly reports its own network location status to the Tracker server unit, including IP address, network description, and specific geographic location description information; especially in the node network within its own network Update the network cluster state when the location changes.

The access control module is responsible for the network access and status of other nodes in the network cluster, and notifies the location management module to update the statistical information when the network location or access mode of other nodes changes.

The general mobile terminal unit includes a session management module, an access management module, a Peer information maintenance unit and a data transmission module;

The session management module: responsible for signaling interaction with the Tracker server and the mobile agent, the signaling is based on the improvement of the Bittorrent protocol, not only can support the general Bittorrent software, but also increases the network access type, network location description, and mobile agent Inter-RTT extension identifier;

Described access management module: be responsible for obtaining the mode of current mobile terminal network access, and submit session management module, fill in nettype and netdescription extended information; Regularly acquire and mobile proxy node round-trip time RTT at the same time, fill in rttime extended information;

Described Peer information maintenance unit: be used for maintaining the information of the seed node list that this terminal node and Tracker return, as peer_id, ip address, port number, task status; And be responsible for establishing the data connection based on TCP protocol with various child nodes, It is convenient for the data transmission module to download resources from the seed node;

The data transmission module: responsible for the sharing of specific resource data, including downloading data from seed nodes and uploading data by itself as a seed node.

Preferably, the signaling interaction between the mobile proxy node and the general mobile node includes the shared file request message of the general mobile node, the position feedback message and the heartbeat feedback message of the mobile proxy node and the general mobile node, the network interface of the general mobile node input type message.

Further, the optimization selection module, as the core module of the Tracker server unit to realize shared acceleration, adopts the optimization target constraint function selected by the multi-parameter seed node, and selects the seed node list of the node most suitable for the current request file sharing service; The optimization objective constraint function is: i=1, 2...N, where N is the number of seed nodes that can be selected for optimization, P _i is the optimal value of the seed node selected for the i-th reference, and A _i is the seed selected for the i-th reference The normalized value of the access network type of the node, S _i is the normalized value of the upload speed of the seed node selected for the i-th reference, and RTT _i is the normalized mobile node requesting file sharing from the seed node selected for the i-th reference The round-trip time normalized value of , Normalized value for the network access type of a typical mobile node requesting file sharing. The above normalized values are based on the international standard parameters of different network types as reference values.

Furthermore, when selecting the seed node list, the upload rate S of the seed node and the round-trip time RTT value between the general nodes requesting file sharing are related to the specific network situation. The specific considerations are as follows:

When S is large and RTT is small, it indicates that the access network bandwidth of the reference seed node is large, and the network distance with the general mobile node (hereinafter referred to as the request node) requesting file sharing is short, and the optimal value A of the reference seed node is large, as Prioritize the selection of seed nodes;

When S is small and RTT is large, it indicates that the access network bandwidth of the reference seed node is small, and the network distance from the request node is long, and the formed data stream is easily affected by the long-distance network environment, and cannot achieve the effect of file sharing acceleration. Seed nodes should be discarded;

When S is small and RTT is small, it indicates that the access network bandwidth of such nodes is low, but the network distance from the requesting node is short and easy to find. Such seed nodes should be considered as optional nodes, depending on the actual situation. When the number of preferred seed nodes cannot meet the number of requested nodes, such optional nodes can be connected.

When S is large and RTT is large, it indicates that such nodes have high access network bandwidth, but are far away from the requesting node network. At this time, using a new mechanism "intra-cluster propagation", the requesting node notifies the mobile agent node to connect with the remote seed node, obtains resource information, downloads it by the mobile agent node, and then distributes it in the network where the requesting node is located. Finally, the requesting node obtains the required resources.

The extended Bittorrent protocol also includes an extension field numwant, which is described as "the number of other seed nodes that the client expects to obtain from the Tracker server", and netdescription, which is described as "a detailed description of the network where the client is located".

The present invention also provides a kind of accelerated file transmission method based on above-mentioned heterogeneous wireless P2P network file sharing system at the same time, it is characterized in that, comprises the following steps:

Step 1. The general mobile terminal node interacts with the Tracker server as a client, and submits a resource download request; through the extended Bittorrent protocol, transmits parameters such as its access network type, network description information, and mobile proxy node RTT to the Tracker server , as the basis for subsequent selection of seed nodes, when the above parameters change, it will be fed back to the Tracker server at regular intervals;

Step 2. The Tracker server processes the client request and queries the seed node information of the entire network. The seed node information is counted by the Tracker server and stored in a form directory, and the list of seed nodes that match the resources requested by the client is initially screened out. Node information is saved to historical query records, so as to provide shared services for the same requests of other clients;

Step 3. According to the list of seed nodes preliminarily screened, the optimal selection module of the Tracker server refers to the list of candidate seed nodes, and further screens out The optimal candidate seed list for the client and sent to the client;

Step 4. The client receives the optimal seed node list, and connects with these seed nodes to continuously download the required resources;

Step 5. If the client fails to connect to the seed node during the download process, the client sends a feedback message to the Tracker server. The Tracker server re-screens the optimal seed node list according to steps 2 and 3, and sends it to the client, and updates it at the same time Peer node statistics;

Step 6: The client updates the list of optimal seed nodes to download the required resources, and connects to these seed nodes to continue downloading the required resources again.

Compared with the prior art, the present invention has the following advantages:

(1). The present invention adopts a traditional centralized architecture, and only needs to add mobile agent nodes to improve the acceleration function. Maintain the characteristics of "thin client" under the mobile Internet, have no special requirements for the performance of mobile terminals, and will not bring large resource overhead to mobile terminals under the premise of stably improving file sharing performance;

(2). The present invention integrates a variety of characteristic parameters for heterogeneous networks for the Tracker server selection seed node strategy, which is flexible and configurable, independent modules, and can be flexibly changed in different application scenarios;

(3). The present invention improves and is downwardly compatible with the Bittorrent protocol, facilitates the acquisition of parameters such as network location and access network type by the mobile terminal, and can be correctly resolved with the Tracker server.

In the scenario proposed by the present invention, any number of networks can be overlapped and merged in any way, and has nothing to do with the specific network underlying technology. It is applicable to existing and future various new wireless network access, and has scalability.

Description of drawings

The technical solutions of the present invention will be further specifically described below in conjunction with the accompanying drawings and specific embodiments.

FIG. 1 is a network architecture diagram of the heterogeneous wireless P2P network file sharing system of the present invention.

FIG. 2 is a functional block diagram of a Tracker server, a mobile agent node and a general mobile node in the present invention.

Fig. 3 is a schematic diagram of a mobile agent node selection model in the present invention;

Fig. 4 is a working flowchart of file sharing acceleration performed by mobile terminal nodes in the present invention.

Detailed ways

Fig. 1 describes the structure diagram of the improved centralized mobile P2P network of the present invention. The heterogeneous network types described in the figure include WLAN, 3G/LTE, and Ad hoc networks, which can fully represent the current popular wireless network access forms. The centralized P2P network architecture also has the characteristics of distributed P2P, and the nodes in the fully distributed P2P network are connected to the centralized architecture through mobile proxy nodes. The network includes Tracker server nodes, mobile proxy nodes and general mobile nodes, and the general mobile nodes connected to the mobile proxy nodes together form a network cluster.

Among them, the Tracker server node provides neighbor node index and selection information, routing information, P2P node discovery, network topology statistics and multicast group management functions for general mobile nodes in the centralized P2P network.

As the network access agent of general mobile nodes, the mobile proxy node will exist in the network for a long time, and maintain a stable network location and online status, and serve as a reference point for the Tracker server node to analyze the network topology;

Generally, mobile nodes are connected to their respective distributed P2P networks through mobile proxy nodes, and regularly feed back their own network access type and round-trip time RTT to the Tracker server node, which is convenient for the Tracker server node to optimize the selection of seed node strategies and accelerate file sharing.

Fig. 2 has described the file sharing acceleration model in the present invention, relates to the function block diagram of Tracker server, mobile agent, general mobile terminal. Each module of each unit is described in detail below.

Tracker server unit, interactive control module: responsible for signaling interaction with mobile agent nodes and general mobile nodes, based on the extended Bittorrent protocol; including general mobile node shared file request messages, mobile agent nodes and general mobile node position feedback messages And heartbeat feedback message, general mobile node network access type message, etc. The above messages are all extended and encapsulated with HTTP GET messages.

Peer management module: Complete the discovery, statistics and recording of mobile proxy nodes and general mobile nodes in each distributed P2P network under the entire centralized P2P network, establish a unified real-time Peer information management database for the entire network, and use it as an optimization selection module for seeding Peer information source selected by the node.

Optimizing selection module: As the core module of the Tracker server unit to realize shared acceleration, it adopts the optimization target constraint function of multi-parameter seed node selection, selects the seed node list of the node most suitable for the current request file sharing service, and maximizes the file sharing speed. The optimization objective constraint function is: i=1, 2...N, where N is the number of seed nodes available for optimization, P _i is the optimal value of the seed node selected for the i-th reference, and A _i is the seed selected for the i-th reference The normalized value of the node's access network type, S _i is the normalized value of the upload speed of the seed node selected for the i-th reference, and RTT _i is the normalized mobile node requesting file sharing from the seed node selected for the i-th reference The round-trip time normalized value of , Normalized value for the network access type of a typical mobile node requesting file sharing. The above normalized values are based on the international standard parameters of different network types as reference values.

Due to the obvious differences in the access network bandwidth of WLAN, 3G/LTE, and Ad hoc networks, when calculating the optimal value of the seed nodes under the above three types of networks, the access network type values A _i , as the main index. The upload rate S of the seed node and the RTT value of the round-trip time between the general nodes requesting file sharing are related to the specific network situation. The specific considerations are as follows:

When S is large and RTT is small, it indicates that the access network bandwidth of the reference seed node is large, and the network distance with the general mobile node (hereinafter referred to as the request node) requesting file sharing is short, and the optimal value A of the reference seed node is large, as Prioritize the selection of seed nodes;

When S is small and RTT is large, it indicates that the access network bandwidth of the reference seed node is small, and the network distance from the request node is long, and the formed data stream is easily affected by the long-distance network environment, and cannot achieve the effect of file sharing acceleration. Seed nodes should be discarded;

When S is small and RTT is small, it indicates that the access network bandwidth of such nodes is low, but the network distance from the requesting node is short and easy to find. Such seed nodes should be considered as optional nodes, depending on the actual situation. When the number of preferred seed nodes cannot meet the number of requested nodes, such optional nodes can be connected.

When S is large and RTT is large, it indicates that such nodes have high access network bandwidth, but are far away from the requesting node network. At this time, using a new mechanism "intra-cluster propagation", the requesting node notifies the mobile agent node to connect with the remote seed node, obtains resource information, downloads it by the mobile agent node, and then distributes it in the network where the requesting node is located. Finally, the requesting node obtains the required resources.

Network analysis module: regularly obtain the reports of mobile agent nodes on their respective network locations, including IP addresses, network descriptions, and specific geographical location description information; regularly obtain IP addresses reported by general mobile nodes, gateway address information, and mobile agent nodes in the network and based on the above information, analyze the logical topology structure of each distributed P2P network, and count the end-to-end RTT value of the mobile node, which is convenient for the optimization selection module to calculate the optimal value of each reference seed node.

Figure 3 shows a schematic diagram of the mobile agent node selection model, the selection mainly includes the number M of nodes (M=6 in Figure 3, identifying 6 independent wireless networks) and the location L, the appropriate M and L can correctly identify the entire network The logical structure of the P2P network and the network location of each node help to improve the performance of the Tracker server in selecting seed nodes. The selection of mobile agent nodes follows three conditions: (1) Maximum separation: due to the characteristics of distributed and overlapping fusion of heterogeneous networks, in order to effectively identify a network location, it is necessary to separate the overlapping networks logically, so that M Mobile agent nodes are evenly distributed in each network, and its average network distance is the smallest, which can uniquely represent each network, and it is also convenient for general mobile nodes to find the mobile agent node closest to itself in terms of network distance; (2) M cluster network set: M A mobile agent node represents the actual M networks. Although the general mobile nodes are unevenly distributed in the network, they are logically clustered in the form of clusters, and each general mobile node belongs to a unique cluster. ; (3) The average distance of the nodes in the cluster is the smallest: In order to keep the logical network topology corresponding to the actual network distribution, the selected mobile agent position should have the smallest average distance from other nodes in the cluster. When the inter-network distance changes), the mobile agent node can effectively reflect the change in the cluster (the change of the logical network topology). When the distance in the cluster is smaller, the nodes in the cluster are closer, which can well adapt to the mechanism that when S is large and RTT is large, the mobile agent node in the cluster is selected to first obtain the resources of the remote seed node, and then spread in the cluster.

Mobile agent unit, location management module: as the central node of the network cluster, the mobile agent unit regularly reports its own network location status to the Tracker server unit, including IP address, network description, and specific geographic location description information; especially in its own network Update the network cluster state when the node network position changes.

Access control module: Responsible for the network access and status of other nodes in the network cluster, and notify the location management module to update the statistical information when other nodes change their network locations or access methods.

General mobile terminal unit, session management module: responsible for signaling interaction with the Tracker server and mobile agent. The signaling is based on the improvement of the Bittorrent protocol. It can not only support the general Bittorrent software, but also increase the network access type, network location description, The identifier of the RTT extension between the mobile agent and the mobile agent. The extended signaling parameters for interacting with the Tracker server are shown in the following table:

Access management module: responsible for obtaining the current mobile terminal network access method, and submitting the session management module, filling in the nettype and netdescription extension information; at the same time, regularly obtaining the round-trip time RTT with the mobile agent node, and filling in the rttime extension information;

Peer information maintenance unit: It has the same function as the corresponding module of general P2P software, maintains the information of the seed node list returned by the terminal node and Tracker (such as peer_id, ip address, port number, task status, etc.); and is responsible for establishing with various child nodes The data connection based on the TCP protocol is convenient for the data transmission module to download resources from the seed node.

Data transmission module: responsible for the sharing of specific resource data, including downloading data from seed nodes and uploading data as a seed node.

Specifically, as shown in FIG. 4 , for a specific application of the present invention, a general mobile terminal node is a workflow flowchart for file sharing acceleration, including the following steps:

Step 100: When building this centralized P2P file sharing network, select a unique mobile proxy node for each independent network of the current heterogeneous network (including M wireless access networks), and M mobile proxy nodes pass ICMP messages Determine the RTT value of the round-trip time between each other, and the M mobile agent nodes are kept in a stable state as the network position reference point of the entire heterogeneous network;

Step 200: The general mobile terminal node interacts with the Tracker server as a client, and makes a resource download request. Through the extended Bittorrent protocol, parameters such as the access network type, network description information, and mobile proxy node RTT are passed to the Tracker server as the basis for subsequent selection of seed nodes. When the above parameters change, they are regularly fed back to the Tracker server ;

Step 300: The Tracker server processes the client request, queries the seed node information of the entire network, the seed node information is counted by the Tracker server and stored in a form directory, initially screens out a list of seed nodes that match the resources requested by the client, and at the same time lists such seed nodes Node information is saved to historical query records, so as to provide shared services for the same requests of other clients;

Step 400: According to the seed node list preliminarily screened, the number of candidate seed nodes in this list exceeds the maximum number of seed nodes required by the client, and the specific conditions of each seed node are different, such as the network distance from the requesting client node, Upload rate, round trip time RTT, network access type, etc. Therefore, in order to achieve the goal of optimal selection for shared acceleration, the Tracker server optimization selection module refers to the list of candidate seed nodes, and further screens the network distance between the client and the candidate seed nodes through the network analysis module, combined with the optimal selection strategy Produce the best candidate seed list for the client and send it to the client;

Step 500: the client receives the list of optimal seed nodes, and connects with these nodes to continuously download the required resources; if any node in the optimal seed node list leaves the heterogeneous network environment during this process (the Unable to connect to the seed node), the client feeds back this situation to the Tracker server, and the Tracker server will re-screen the optimal seed node list according to steps 300 and 400, and send it to the client, and update the Peer node statistics at the same time; the client updates The optimal seed node list performs the download process of the required resources to ensure that the download rate of the client is maximized throughout the process.

To sum up, according to the centralized P2P network structure and acceleration method of the present invention, there is a reasonable selection of seed nodes in the entire heterogeneous network, which can not only achieve the effect of network acceleration, but also achieve the effect of network acceleration for the longer the distance from the download client and the higher the upload rate. The lower the seed node is, the less likely it is to be selected; while the seed node with high upload rate and short distance is selected by cable, and this is also in line with the characteristics of information spread under the mobile Internet in real scenarios, especially for the expansion of resource dissemination situation. Considering the upload rate of seed nodes, network distance, round-trip time RTT, and access network type factors, the overall download time of resource files will be reduced, and the long-distance data traffic will be greatly reduced, and the short-distance network traffic will increase, making the entire P2P network Balanced traffic distribution also improves network performance; at the same time, the set mobile proxy node can not only exist as a general mobile terminal node, but also serve as a reference node for network location. To expand the wireless network where it is located, other functional units can be added to the mobile proxy node without affecting the structure of the entire network.

Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and not limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the present invention can be Modifications or equivalent replacements of the technical solutions without departing from the spirit and scope of the technical solutions of the present invention shall fall within the scope of the claims of the present invention.

Claims (3)

1. a heterogeneous wireless P2P network file shared system, is characterized in that, comprises Tracker server, mobile agent node, general mobile node;

Described Tracker server, comprises interactive controlling module, Peer administration module, optimum choice module and nework analysis module;

Described interactive controlling module: for the Signalling exchange between described mobile agent node, general mobile node, described Signalling exchange is based on the Bittorrent agreement of expansion; The Bittorrent agreement of described expansion comprises extended field nettype, and it is described as " client access network type ", rttime, and it is described as " client is to RTT two-way time of mobile agent node ";

Described Peer administration module: for realizing mobile agent node in whole distributed P 2 P network, the discovery of general mobile node, statistics and record, set up the real-time Peer MIB of unified whole network, carry out the Peer information source of seed node selection as optimum choice module;

Optimum choice module: for selecting the seed node list of the general mobile node adapting to current request file-sharing business most, maximizes file-sharing speed; Described optimum choice module adopts optimum target constraint function, sets up seed node list; Described optimum target constraint function is: i=1,2......N, wherein N is can for the seed node number of optimum choice, P _ibe the seed node optimal value that i-th reference is chosen, A _ibe access network type normalized value, the S of the seed node that i-th reference is chosen _ibe the uploading speed normalized value of the seed node that i-th reference is chosen, RTT _ibe normalized value two-way time of the general mobile node that seed node that i-th reference is chosen is shared to demand file, for the network insertion type normalized value of the general mobile node that demand file is shared; Described optimum target constraint function sets up seed node list, comprises following selection:

Work as S _igreatly, RTT _ihour, show that this reference seed node access network band is roomy, and the general mobile node network distance shared with demand file is short, the optimal value A of this reference seed node is large, as prioritizing selection seed node;

Work as S _ilittle, RTT _itime large, show that this reference seed node access network bandwidth is little, and the network distance of the general mobile node shared with demand file is long, the data flow of formation is easily by long-range network environmental impact, cannot reach the effect that file-sharing is accelerated, this type of seed node should abandon;

Work as S _ilittle, RTT _ihour, show that this reference seed node access network bandwidth is low, but short with requesting node network distance, easily find; As optional seed node;

Work as S _igreatly, RTT _itime large, show that this reference seed node access network bandwidth is high, but far away with requesting node network distance, and this reference seed node is as special far-end seed node; The general mobile node notice mobile agent node that demand file is shared is connected with this far-end seed node, Gains resources information, and downloaded by mobile agent node, then distribute in the general mobile node place net that demand file is shared, the general mobile node that final demand file is shared gets resource requirement;

Described nework analysis module: for timing acquisition mobile agent node reporting respective network site, specifically comprise IP address, network description, particular geographic location descriptor; RTT value between mobile agent node in the IP address that the general mobile node of timing acquisition reports, gateway address information and net; And for above information, analyze the logical topological structure of each distributed P 2 P network, add up general mobile node RTT value end to end;

Described mobile agent node comprises location management module and access control module;

Described location management module: the network site state reporting self for timing to described Tracker server, comprises IP address, network description, particular geographic location descriptor; Network cluster collection state is upgraded when own net interior nodes network site changes;

Described access control module: for network insertion and the state of other nodes in network cluster collection, and when network site change or access way change occur other general mobile nodes, notify that described location management module carries out statistical information renewal;

Described general mobile node unit comprises session management module, Access Management, Peer information maintenance unit and data transmission module;

Described session management module: for carrying out Signalling exchange between described Tracker server, mobile agent node, Signalling exchange is based on the Bittorrent agreement of expansion;

Described Access Management: for obtaining the mode of current general mobile node network insertion, and submit described session management module to,

Described Peer information maintenance unit: for safeguarding the information of the seed node list that general mobile node and described Tracker server return; And be responsible for setting up data cube computation based on Transmission Control Protocol with each seed node, be convenient to data transmission module from seed node downloaded resources;

Described data transmission module: be responsible for sharing of concrete resource data, comprises from seed node downloading data and self is as seed node uploading data.

2. heterogeneous wireless P2P network file shared system according to claim 1, it is characterized in that, Signalling exchange between described mobile agent node and general mobile node, comprise the shared file request message of general mobile node, the position feedback message of mobile agent node and general mobile node and heartbeat feedback message, general mobile node network insertion kind of message.

3. heterogeneous wireless P2P network file shared system according to claim 1 and 2, it is characterized in that, the Bittorrent agreement of described expansion also comprises extended field numwant, it is described as " client wishes the number of other seed node obtained from Tracker server ", netdescription, it is described as " client place network detailed description ".