Peer-to-Peer Connections
using JXTA
情報科学部ディジタルメディア学科
n00k1042 山崎 剛
Peer-to-peer Connections
PDP: Peer Discovery Protocol
他のpeerへリソースなど(Advertisement)を公開
公開されたAdvertisementの取得
PBP: Pipe Binding Protocol
Pipeは他のpeerとのコミュニケーションに使用
Pipe Advertisementの公開(publish)
Pipe Advertisementの検索・獲得(discovery/get)
入出力Pipeの作成
1. アドバータイズメント公開
Peer
Pipe
Adv.
2. アドバータイズメント検索
3.応答からPipe Adv.取得
4.Pipe入出力でMessageやり取り
(Peer間で共通)
Pipe
Peer
Peer-to-peer Connections(Cont.)
1. アドバータイズメント作成 ( Pipe Advertisementを公開するpeerのみ )
Get Discovery Service from NetPeerGroup
Creating Pipe Advertisement
discSvc = netPeerGourp.getDiscoveryService();
PipeAdvertisement pipeAdv= (PipeAdvertisement)
AdvertisementFactory.newAdvertisement(PipeAdvertisement.getAdvertise
mentType);
publish Pipe Advertisement (Local/Remote)
discSvc.publish(pipeAdv, DiscoveryService.ADV);
discSvc.remotePublish(pipeAdv, DiscoveryService.ADV);
1. アドバータイズメント公開(publish)
Peer
Pipe
Adv.
Peer
Peer-to-peer Connections(Cont.)
2. アドバータイズメント検索 ( Pipe Advertisementを公開するpeerのみ )
Get Discovery Service from NetPeerGroup
discSvc = netPeerGourp.getDiscoveryService();
Discovering Pipe Advertisement (Remote:相手のPeerのPipeAdv.検索)
discSvc.getRemoteAdvertisements(null, DiscoveryService.ADV, null, null, 5, this);
3. 応答からPipeAdvertisementを取得
Creating Pipe – Get Pipe Advertisement from response
Peer
public void discoveryEvent(DiscoveryEvent evt) {
DiscoveryResponseMsg res = evt.getResponse(); // 応答の取得
…
// 応答がPipeAdvertisementだった場合
if (adv instanceof PipeAdvertisement)
pipeAdv = (PipeAdvertisement) adv;
}
2. アドバータイズメント検索
(Discovery)
Pipe
Adv.
3.応答からPipe Adv.取得
Pipe
Peer
Peer-to-peer Connections(Cont.)
4. 入出力Pipeの作成 (両方のPeerで行う)
Creating Pipe(input/output)
pipeSvc = netPeerGroup.getPipeService();
inputPipe = pipeSvc.createInputPipe(pipeAdv,this);
(このクラスはPipeMsgListenerをインプリメントする必要がある)
outputPipe = pipeSvc.createOutputPipe(pipeAdv,TIME_TO_WAIT);
Send Message
Message msg = pipeSvc.createMessage(); …
outputPipe.send(msg);
Receive Message (inputPipeのPipeMsgEventを受け取る)
public void pipeMsgEvent(PipeMsgEvent evt)
{ Message msg= evt.getMessage(); … }
Peer
Pipe 4.Pipe入出力でMessageやり取り
Pipe
Adv.
Peer
Example:Stream Socket Connections
(TCP:transmission control protocol)
CloseWindowAndExit.java
The basic life cycle of a server is:
ServerTCP.java
•A creation of a ServerSocket
-- ServerSocket server = new ServerSocket(5000,100);
•Listen for incoming connection
-- Socket connection = server.accept();
•Receive data
-- DataInputStream input = new DataInputStream(connection.getInputStream());
•Send data
-- DataOutputStream output = new DataOutputStream(connection.getOutputStream());
input.readUTF();
output.writeUTF(“connected!”);
•Close the connection
-- connection.close();
•Wait for the next connection.
What a client does:
ClientTCP.java
•Connect to a remote machine -- Socket client = new Socket(InetAddress.getLocalHost(),5000);
•Receive data
-- DataInputStream input = new DataInputStream(client.getInputStream());
input.readUTF();
•Send data
-- DataOutputStream output = new DataOutputStream(client.getOutputStream());
output.writeUTF(“Thanks!”);
•Close a connection
-- client.close();
Socket connection
Output.writeUTF
Client
Input.readUTF(
)
Input.readUTF(
)
Output.writeUTF
Socket client
5000
Server
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