diff --git a/ws2012/P2P/uebungen/11/src/node/ChunkIdentifier.java b/ws2012/P2P/uebungen/11/src/node/ChunkIdentifier.java
new file mode 100644
index 00000000..3bc9143f
--- /dev/null
+++ b/ws2012/P2P/uebungen/11/src/node/ChunkIdentifier.java
@@ -0,0 +1,36 @@
+package node;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
+public class ChunkIdentifier extends Identifier {
+	
+	private String chunkID;
+	private FileIdentifier fileID;
+
+	public ChunkIdentifier(int size, byte[] bytes, FileIdentifier fileID, String chunkID) {
+		super(size, bytes);
+		
+		this.fileID = fileID;
+		
+		//calculate SHA-256 Hash of chunckID
+		try {
+			MessageDigest md = MessageDigest.getInstance("SHA-256");
+			md.update(chunkID.getBytes());
+			this.chunkID = md.digest().toString();
+		} catch (NoSuchAlgorithmException e) {
+			// TODO Auto-generated catch block
+			e.printStackTrace();
+		}
+		
+	}
+	
+	public String getChunkID() {
+		return this.chunkID;
+	}
+	
+	public FileIdentifier getFileID(){
+		return this.fileID;
+	}
+
+}
diff --git a/ws2012/P2P/uebungen/11/src/node/FileIdentifier.java b/ws2012/P2P/uebungen/11/src/node/FileIdentifier.java
index 470390a2..bd5cdef1 100644
--- a/ws2012/P2P/uebungen/11/src/node/FileIdentifier.java
+++ b/ws2012/P2P/uebungen/11/src/node/FileIdentifier.java
@@ -5,16 +5,16 @@ import java.security.NoSuchAlgorithmException;
 
 public class FileIdentifier extends Identifier {
 	
-	private String key;
+	private String fileID;
 
-	public FileIdentifier(int size, byte[] bytes, String key) {
+	public FileIdentifier(int size, byte[] bytes, String fileID) {
 		super(size, bytes);
 		
 		//calculate SHA-256 Hash of key
 		try {
 			MessageDigest md = MessageDigest.getInstance("SHA-256");
-			md.update(key.getBytes());
-			this.key = md.digest().toString();
+			md.update(fileID.getBytes());
+			this.fileID = md.digest().toString();
 		} catch (NoSuchAlgorithmException e) {
 			// TODO Auto-generated catch block
 			e.printStackTrace();
@@ -23,6 +23,6 @@ public class FileIdentifier extends Identifier {
 	}
 	
 	public String getKey() {
-		return this.key;
+		return this.fileID;
 	}
 }
diff --git a/ws2012/P2P/uebungen/11/src/node/Node.java b/ws2012/P2P/uebungen/11/src/node/Node.java
index a9a53e76..eb92b7b0 100644
--- a/ws2012/P2P/uebungen/11/src/node/Node.java
+++ b/ws2012/P2P/uebungen/11/src/node/Node.java
@@ -181,6 +181,15 @@ public class Node {
                     new Object[] { fileID, receiver });
         }
     }
+    
+    public void sendData(NodeIdentifier receiver, FileIdentifier fileID, ChunkIdentifier chunckID){
+    	
+    	//TODO: implement
+    	
+    	
+    	
+    }
+    
 
     public void sendPing(NodeIdentifier receiver, MessageCallback cb) {
         boolean successful = send(receiver, MessageType.PING, null, true, cb);