CN102946441A - Highly-efficient downloading method for P2P (peer-to-peer) file sharing system based on enhanced teamwork - Google Patents

Abstract

The invention relates to a method for improving the downloading efficiency of P2P (peer-to-peer) downloading software by virtue of a teamwork mechanism. The method comprises the following steps of: forming a team by a plurality of P2P nodes for downloading a same file and with the same bandwidth; accumulating uploading traffics of a member node in the team; distributing an uploading traffic value to a node with a maximum uploading traffic value in the team; and in the case that the member nodes in the team upload information, distributing non-blocking to the node with the maximum uploading traffic value in the team, so as to enable the node to have the priority to obtain a downloading resource and enable the member nodes in the team to have the priority to be bon-blocked, to share the downloading resource with the other member nodes in the team by the member node which has the priority to obtain the downloading resource. The method can be widely applied to the existing P2P-type downloading software.

Description

A kind of efficient method for down loading of P2P shared file system based on enhancement mode team collaboration

Technical field

The present invention relates to efficient resource dissemination technology in the Internet, especially for the technology that improves P2P shared file system download efficiency.

Background technology

In the last few years, more and more extensive based on the diverse network application of P2P, what wherein have the greatest impact was the application of the large-data documents shared systems such as video, image, and had produced thus huge network traffics.Effectively improve the file transfer efficient of P2P agreement, all have very important realistic meaning for the performance of raising network service, the load of reduction network.

Studies show that before, cooperative between the Strengthens network node, give full play to the uploading bandwidth of all nodes, can effectively improve the download efficiency of network, between existing reinforcement P2P node there be cooperative main method: the method (" Improving BitTorrent Network ' s Performance via Deploying Helpers IEEE " 2008) of disposing the help node in the P2P system that A. Ke Xu etc. propose; B. method (" the Uplink Allocation Beyond Choke/Unchoke of the dynamic assignment uploading bandwidth that proposes of Nikolaos Laoutaris " 2008); C. the utilization of Rafit Izhak-Ratzin proposition is based on the method (" Collaboration in BitTorrent Systems " NETWORKING 2009) of the incentive mechanism of bandwidth; Method (" the Improving BitTorrent Download Times Using Community Partners of the small-scale cooperation team that D Marc Espelt Palau proposes ", IEEE 2011).A helps node by introducing in P2P shared file download system, be high bandwidth, high connection, controllable node, solve the download efficiency that exists in the network low and the incomplete problem of shared resource is provided because provide the kind child node of resource to drop by the wayside, help node only need to download a part less in the shared resource, but better optimization system performance, research finds that more help nodes more produce effect than more seeds, but deployment helps and method in this paper is not conflicted.B dynamically adjusts the method for uploading bandwidth, when selecting the unblock node, each node in the P2P system is as far as possible minimum at the nodes of synchronization acquisition unblock, the higher node of those uploading bandwidths of selection that deflection is arranged simultaneously, allow more download nodes obtain faster a complete fragment, solve because node just begins downloaded resources, the resource that does not have to upload causes being difficult to obtain new piece, so that the problem that their uploading bandwidth is not fully used.But this needs each node in the network must know the amount of bandwidth of his peer node, and realizability is lower in current heterogeneous network.The method of C searching same band node has promoted the operation of incentive mechanism, has promoted even exchange.The node that bandwidth in the network is similar all is put into one " group " the inside, impel between the node of same " group " mutual mutually by the selection that deflection is arranged, reduce the data sharing (namely as far as possible reducing between the different bandwidth node mutual) between different " group ", be that the simple data interaction with between the different bandwidth node is kept apart, thereby be easy to cause the high bandwidth node to be easier to finish download, and low bandwidth node speed of download still slowly.D is the method for cooperation team on a small scale, arrive in one by one little " group " by the node rendezvous that will download same file, the node more to own uploading data among the member in preferential this group of unblock of member in little " group ", simultaneously preferential all minimum resource fragments of " group " member degree of having of downloading.Because the existence of bandwidth difference causes the downloading rate between the inner member of group widely different, the very difficult advantage of bringing to obtain " group " member of " group " inner low bandwidth node.As seen under the prerequisite of other node interests of sacrificial system not, a kind of easy realization, can strengthen fully that P2P downloads node cooperation, the method that improves P2P shared file system download efficiency is active demand.

Summary of the invention

The invention provides a kind of efficient method for down loading of P2P shared file system based on enhancement mode team collaboration, in order to solve in the present P2P shared file system because node lacks cooperation and the low problem of download efficiency.

A kind of efficient method for down loading of P2P shared file system based on enhancement mode team collaboration, when the P2P shared file is downloaded, to download several identical peer(P2P nodes of bandwidth of same file) set up the upload and download shared resource as a team " large node ", the uploading flow (namely uploading flow value) and this value is assigned to the node of uploading the flow maximum in the team of same Team Member node superposes, other nodes are when uploading information in the team, with unblock to upload in the team flow maximum node, make this node obtain faster downloaded resources, simultaneously preferential unblock between Team Member's node, other member node that allow the member node of preferential acquisition downloaded resources faster resource-sharing be given this team, so that all nodes can more effectively utilize bandwidth resources in the team, improve thus the download efficiency of BT.

Technical scheme of the present invention comprises:

A kind of method that promotes P2P net distribution efficient by strengthening team collaboration, its step comprises: set up team.The node that participates in team collaboration sends the handshake data bag that adds team collaboration's request keyword to neighbor node, request adds team.The request that leading node processing is received adds the handshaking information of team collaboration's request keyword, the node of adhereing to team is returned request pre-by bag.If requesting node after sending request data package in the scheduled time (such as desirable 100 seconds, be enough to allow other leading node return the information of passing through) the pre-bag that passes through of the request of not receiving, expression does not have the team that can add in the network, then node will oneself be converted into a leading node, waits for that other nodes add.Each node that participates in team collaboration is set up a team information tabulation, stores the information such as IP address of each known Team Member, certainly also comprises the IP address information of this Team Member.

After leading node receives that the node request adds the handshaking information of team collaboration, estimate the download bandwidth of requesting node, if the download bandwidth of requesting node is identical with the average download bandwidth of cooperative node in the team and team's interior nodes upper limit less than (as according to bandwidth and QOS requirement, team's nodes upper limit can be set as 4, the setting of this numerical value namely guarantees the gather strength of team, also to consider to have enough abilities, team's node can't be looked after each node in the team too much), then send request to requesting node pre-by bag, the requesting node request of receiving is pre-by after the bag, transmission becomes a full member of team's request bag and ignores request that other leading nodes send in advance by bag, leading node joins the nodal information (comprising bandwidth and node IP address information) of requesting node in the tabulation of this team information after the team's request that becomes a full member of of receiving the requesting node transmission is wrapped, concurrent carry information is notified team's interior nodes, this requesting node has added in this team, leading node sends a request and by bag requesting node is beamed back in the tabulation of this team simultaneously, and requesting node adds smoothly in the team and begins data to be downloaded.

In the data downloading process, share between the same node member of team and upload flow tabulation (uploaded the flow list records data traffic that other nodes are uploaded to this node in the network), when node is selected the unblock node (as obtaining according to emulation experiment, per 10 seconds nodes are again added up the node of uploading are provided according to the nearest 10 seconds flow of uploading of user, make speed of download reach maximum), all members upload the flow of uploading of corresponding node in the flow tabulation in the cumulative team of each team collaboration's member node, obtain team and upload in real time the flow v that tabulates _All, each Team Member has just possessed and identical has uploaded the flow tabulation like this, thus possessed " large node " and globality, then calculate and upload flow tabulation v _AllIn " large node " and always upload flow, namely Team Member uploads the flow summation, uses the flow of uploading that the amount of spreading summation replaces the node of uploading the flow maximum in the team, namely is assigned to the node of uploading the flow maximum in the team uploading the flow summation.According to TFT algorithm (Tit-for-Tat returns like for like, and namely who is many to data that I download, and I just am uploaded to his data), by uploading flow tabulation v _AllOrdering, node is uploaded flow, can make the download node obtain faster downloaded resources, allow a part of node in the team preferentially obtain downloaded resources, simultaneously preferential unblock between the inner member node of team, Team Member's node allow the node that obtains first downloaded resources rapidly downloaded resources be sent to each member node in the team, so that can more effectively utilize their bandwidth resources, the efficiency of transmission that improves according to this.

The node that participates in team collaboration download finish exit network after neighbor node this node of deletion from the team information tabulation, upgrade simultaneously team's number in the leading node.Take node as the leading factor if withdraw from node, then the random node of selecting this group of leading node sends the left packet, is translated into leading node.

The present invention proposes a kind of method that promotes P2P net distribution efficient by strengthening team collaboration, allow the similar some nodes of bandwidth appear in the network with the form of " large node ", can strengthen to greatest extent saving the cooperative between the P2P node, in order not damage the download efficiency of other ordinary nodes in the network, guarantee to have at least an ordinary node and team's node to obtain unblock simultaneously.This method has the characteristics of compatible team collaboration node and common download node, ordinary node is receiving that the team that adds team information and handshaking information can directly neglect when asking keyword message, do not disturb common P2P to download the operating mechanism of node, these information only need to take seldom byte, can not increase offered load, have realizability.Superpose by the flow of uploading with the low bandwidth node simultaneously, can effectively promote the download efficiency of low bandwidth node.The method of this reinforcement P2P download efficiency can effectively promote the raising of node download efficiency, is widely used in existing P2P class and downloads in the downloading process of software: BT, electric donkey, a sudden peal of thunder.

Description of drawings

Fig. 1 team node adds flow through a network figure;

Fig. 2 team node unblock flow chart;

Fig. 3 team request data package structure chart.

Embodiment

Below for accompanying drawing and instantiation enforcement of the present invention is described in further detail.Be illustrated in figure 1 as node and add team's flow chart.

A. node adds team, makes up team.

According to network environment and scale team's nodes upper limit is set, each team collaboration's node is set up a team information tabulation, store the IP address information of each Team Member of the IP address information that comprises all members of this team, this request keyword only takies 1 byte, can not increase offered load.Simultaneously the leading node of non-team can be ignored this request keyword, its structure as shown in Figure 3, packet comprises Ethernet head, IP head, agreement, purpose IP, TCP head, load data message format.

The node request adds team, and node adds request and adds team's keyword (teamq) in handshaking information, and sends handshaking information to neighbor node, and request adds team.The request that leading node processing is received in the network adds the handshaking information of team collaboration's request keyword, leading node at first passes through the download bandwidth of bandwidth estimation analysis request node, if the download bandwidth of requesting node is identical with the average download bandwidth of Team Member's node, and team's internal segment is counted and is not reached node upper limit number, and the request that then sends agrees that to requesting node node adds this team by bag in advance.Wherein can be according to formula, download/k of the continuous k of an EB=requesting node time is to node j estimated bandwidth EB.

Node sends download request, the leading node of team judges that the handshaking information of receiving is that ordinary node sends, or team collaboration's node sends, and ordinary node sends in this way, or team collaboration's nodes of this team reached the node upper limit, then carries out normal common download.The requesting node request of receiving is pre-by after the bag, send become a full member of team's request bag send in advance the leading node by bag to first and ignore after the request that sends over of other leading nodes in advance by bag.Leading node is after the team's request that becomes a full member of of receiving the requesting node transmission is wrapped, leading node joins the nodal information (comprising bandwidth and node IP address information) of this requesting node in the team information tabulation, send a request and return requesting node by bag and team's tabulation, all team's nodes and neighbor node send " adding team information " in tabulating to team information simultaneously, Team Member's node updates team information tabulation, wherein, add team information and mainly comprise the IP address information that adds Team Member.Then requesting node will oneself be converted into a leading node by bag if requesting node (according to emulation experiment, optimum can be 10 unblock time intervals, namely 100 seconds) in the predetermined time interval request of not receiving is pre-, waits for that other nodes add.The requesting node request of receiving participates in data and downloads by wrapping the corresponding team of rear adding and beginning as a Team Member.

Better, request also can be converted into a request by keyword by bag, when node sends handshaking information and exchanges bitmap list, is carried in the bitmap list that the neighbor node tabulation returns, and only needs the space of a byte.By to the neighbor node bandwidth estimation, prevent that wrong report from appearring in node, the situation of false newspaper.Before node adds team, leading node preferentially gives requesting node and (generally gets k=3 unblock time with form k unblock time interval of download of ordinary node, can effectively estimate the bandwidth of requesting node), be convenient to the bandwidth that allows leading node add up him.

B. team's node downloading data stage.

Team's node is selected the unblock node.In the team during a certain member node downloading data, from this Team Member and ordinary node, extract respectively a node to this node uploading data amount maximum and preferentially add the unblock formation, and then with other nodes in other nodes and the neighbor list in the team by uploading flow ordering, can utilize the TFT algorithm, the residue unblock node (being that uploading data is to the maximum node of this team node) of flow maximum is uploaded in searching, and gives and its unblock.Upload the consistency that flow tabulates to guarantee Team Member's unblock node by sharing between team's node simultaneously.

As shown in Figure 2, in order not damage the download efficiency of other ordinary nodes in the network, other nodes is indispensable alternately in while team's node and the network, guarantees to have at least a non-team node and team's node to obtain unblock.Simultaneously in order to guarantee the consistency of Team Member's unblock node, cooperative node in a team by Fixed Time Interval (as being made as per 10 seconds once) mutually send separately upload flow tabulation (Team Member's tabulation and to upload the flow tabulation very little, data traffic can increase hardly).Team Member's node when determining unblock, at first with Team Member upload corresponding node in the flow tabulation to upload flow cumulative, obtain a team and upload in real time flow tabulation v _All, each Team Member has just possessed and identical has uploaded the flow tabulation like this, thus this team possessed " large node " and globality, then calculate v _AllIn each " large node " and always upload flow, be that Team Member uploads the flow summation, and use that the amount of spreading summation replaces the node of uploading the flow maximum in the team upload in real time flow, and the flow of uploading in real time that will remain Team Member sets to 0, then node decides the neighbor node that will obtain unblock by the tabulate flow of uploading in real time of each node of ordering flow, must guarantee to have at least this team node and an ordinary node acquisition unblock.

Setting up the flow of uploading of arbitrary node i tabulates:

, wherein,

N the neighbor node that expression is recorded in the node i upload in real time flow (wherein, n for upload flow tabulate in the neighbor node number).

Set such as all nodes in the network is N, and defined node i place team set of node is g _i={ n _T1, n _T2..., n _Tlast,

, for each node n _Tj∈ g _iThe flow tabulation of uploading in real time of its correspondence is respectively V _TjNode i is carried out team collaboration when download selecting the unblock node, at first, uploads flow tabulation V with what Team Member shared _T1, V _T2..., V _TlastMiddle corresponding node upload in real time flow cumulative the new flow tabulation v that uploads _All:

$v_{\mathrm{all}}=\left\{v_{\mathrm{all}}^k\right|v_{\mathrm{all}}^k=\underset{j=1}{\overset{\mathrm{last}}{\mathrm{\Σ}}}{v}_{\mathrm{tj}}^k,1\≤k\≤n\}$

Suppose the neighbor node collection fn={n of nodes i ₁, n ₂..., n _TeamnumBe all node members of another team, correspondence is uploaded flow tabulation v in node i _AllIn the flow of uploading be:

, node i find set of node fn corresponding upload flow

Middle maximum:

$v_{\mathrm{all}}^N=\max \{v_{\mathrm{all}}^1,v_{\mathrm{all}}^2,...,v_{\mathrm{all}}^{\mathrm{teamnum}}\}$

Suppose the node n that it is corresponding _x∈ fn (1≤x≤teamnum), then put node n _xThe flow of uploading in real time be

$v_{\mathrm{all}}^x=\underset{j=1}{\overset{\mathrm{teamnum}}{\mathrm{\Σ}}}{v}_{\mathrm{all}}^j$ , and put: $v_{\mathrm{all}}^1=v_{\mathrm{all}}^2=...=v_{\mathrm{all}}^{x-1}=v_{\mathrm{all}}^{x+1}=0$

Wherein, teamnum is nodes among the node set fn, and last is nodes in the team.

Like this, can be so that node n _xPreferential acquisition unblock is as node n _xWhen downloading to a piece, their Team Member can be from n _xThe there preferentially obtains this piece, takes full advantage of like this bandwidth resources of team's node.

Team's node is finished in download and is exitted network, and will send each neighbor node in the network and withdraw from packet, and the friendly neighbour of team collaboration node is this node of deletion from the team information tabulation.Take node as the leading factor if withdraw from node, leading node is then selected the node of this group at random, is assumed to be N, tells this team all members by sending the left packet, and node N will be converted into the leading node of this team.

Claims (6)

1. P2P shared file system method for down loading based on enhancement mode team collaboration, it is characterized in that, comprise: several the identical P2P nodes of bandwidth that will download same file form team, cumulative same Team Member node upload flow, and will upload flow value and be assigned to the node of uploading the flow maximum in the team, when Team Member's node is uploaded information, Team Member's node determination unblock, and with unblock to the node of uploading the flow maximum in the team, make this node preferentially obtain downloaded resources, simultaneously preferential unblock between Team Member's node allows the member node of preferential acquisition downloaded resources downloaded resources be shared to other member node of team.

2. method for down loading according to claim 1, it is characterized in that, described composition team specifically comprises: ask team to be added node to add request in handshaking information and add team's keyword, and to neighbor node transmission handshaking information request adding team, the handshaking information that contains request adding team keyword that leading node is received is returned request to the node of adhereing to team pre-by bag; Ask the request of receiving of team to be added node pre-by bag, add team's request bag and ignore request that other leading nodes send in advance by bag to leading the transmission, after leading node is received and is become a full member of team's request bag, the nodal information of request team to be added node is joined in the tabulation of this team information, concurrent carry information is notified other member node in the team, Team Member's node is set up a team information tabulation, stores the IP address information of each known Team Member.

3. method for down loading according to claim 1, it is characterized in that, after the request of receiving of leading node adds the handshaking information of team collaboration, download bandwidth according to bandwidth estimation request team to be added node, if the download bandwidth of asking team to be added node is identical with the team average download bandwidth of interior nodes and team's interior nodes upper limit less than, then send request to requesting node pre-by bag.

4. method for down loading according to claim 1, it is characterized in that, described method further comprises: in the team during a certain member node downloading data, from this Team Member and ordinary node, extract respectively a node to this node uploading data amount maximum and preferentially add the unblock formation, other nodes in other nodes and the neighbor list in the team are sorted by uploading flow, the residue unblock node of flow maximum is uploaded in searching, and gives and its unblock.

5. method for down loading according to claim 1 is characterized in that, Team Member's node when determining unblock, with Team Member upload node in the flow tabulation to upload flow cumulative, obtain team and upload in real time flow tabulation v _All, calculate and upload flow tabulation v _AllMiddle Team Member uploads the flow summation, and use that the amount of spreading summation replaces the node of uploading the flow maximum in the team upload in real time flow, and the flow of uploading in real time that will remain Team Member sets to 0.

6. method for down loading according to claim 2 is characterized in that, if the request of not receiving is in advance by bag in the scheduled time after sending handshaking information for requesting node, requesting node will oneself be converted into a leading node, waits for that other nodes add.

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