diff --git a/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/BufferedNetworkStack.java b/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/BufferedNetworkStack.java
index 3f5c8e27..3d6e8ee2 100644
--- a/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/BufferedNetworkStack.java
+++ b/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/BufferedNetworkStack.java
@@ -114,9 +114,9 @@ class BufferedNetworkStack {
 
 			case MessageType.CMD_POP:
 				try {
-					// Element popped = stack.pop();
-					// send(popped.toString(), client);
-					// System.out.println("Pop " + popped);
+					String popped = stack.pop();
+					send(popped, client);
+					System.out.println("Pop " + popped);
 				} catch (EmptyStackException e) {
 					System.out.println("Received pop but stack is empty");
 				}
diff --git a/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/BufferedNetworkStackClient.java b/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/BufferedNetworkStackClient.java
index 626be28f..41d72f86 100644
--- a/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/BufferedNetworkStackClient.java
+++ b/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/BufferedNetworkStackClient.java
@@ -6,6 +6,8 @@ import java.nio.ByteBuffer;
 import java.nio.channels.DatagramChannel;
 
 public class BufferedNetworkStackClient {
+	protected static final long TIMEOUT = 5000;
+
 	protected static final int BUF_SIZE = 128;
 
 	private DatagramChannel channel = null;
@@ -15,7 +17,8 @@ public class BufferedNetworkStackClient {
 		buf = ByteBuffer.allocate(BUF_SIZE);
 	}
 
-	public void push(String s, String host, int port) throws IOException {
+	public void push(String s, String host, int port) throws IOException,
+			TimeoutException {
 		if (channel == null) {
 			channel = DatagramChannel.open();
 		}
@@ -33,7 +36,16 @@ public class BufferedNetworkStackClient {
 
 		buf.flip();
 		buf = ByteBuffer.allocate(BUF_SIZE);
-		channel.receive(buf);
+
+		channel.configureBlocking(false);
+		long time = System.currentTimeMillis() + TIMEOUT;
+		while (buf.remaining() == BUF_SIZE && System.currentTimeMillis() < time) {
+			channel.receive(buf);
+		}
+		if (buf.remaining() == BUF_SIZE) {
+			throw new TimeoutException("ERROR: Buffer empty - no data recieved");
+		}
+		channel.configureBlocking(true);
 
 		byte[] receivedData = buf.array();
 		String infoPacket = new String(receivedData).trim();
@@ -43,6 +55,7 @@ public class BufferedNetworkStackClient {
 		int remoteBufSize = Integer.valueOf(info[0]);
 		int sessionId = Integer.valueOf(info[1]);
 
+		System.out.println('4');
 		sendChunks(s, dest, remoteBufSize, sessionId);
 	}
 
@@ -77,7 +90,8 @@ public class BufferedNetworkStackClient {
 		}
 	}
 
-	public String pop(String host, int port) throws IOException {
+	public String pop(String host, int port) throws IOException,
+			TimeoutException {
 		if (channel == null) {
 			channel = DatagramChannel.open();
 		}
@@ -85,11 +99,19 @@ public class BufferedNetworkStackClient {
 		InetSocketAddress dest = new InetSocketAddress(host, port);
 		channel.send(ByteBuffer.wrap(new byte[] { MessageType.CMD_POP }), dest);
 
-		channel.receive(buf);
+		channel.configureBlocking(false);
+		long time = System.currentTimeMillis() + TIMEOUT;
+		while (buf.remaining() == BUF_SIZE && System.currentTimeMillis() < time) {
+			channel.receive(buf);
+		}
+		if (buf.remaining() == BUF_SIZE) {
+			throw new TimeoutException("ERROR: Buffer empty - no data recieved");
+		}
+		channel.configureBlocking(true);
+
 		byte[] receivedData = buf.array();
 		String strReceived = new String(receivedData).toString().trim();
 
-		System.out.println(strReceived);
 		return strReceived;
 	}
 
diff --git a/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/ClientGUI.java b/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/ClientGUI.java
index 4baca129..e78b2eb5 100644
--- a/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/ClientGUI.java
+++ b/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/ClientGUI.java
@@ -97,9 +97,11 @@ public class ClientGUI extends JFrame {
 					client.print(txtHost.getText(),
 							Integer.valueOf(txtPort.getText()));
 				} catch (NumberFormatException e1) {
-					e1.printStackTrace();
+					textPane.setText(textPane.getText()
+							+ "\nErroneous port number. " + e1.getMessage());
 				} catch (IOException e1) {
-					e1.printStackTrace();
+					textPane.setText(textPane.getText()
+							+ "\nCould not send to server. " + e1.getMessage());
 				}
 			}
 		});
@@ -110,14 +112,18 @@ public class ClientGUI extends JFrame {
 				try {
 					received = client.pop(txtHost.getText(),
 							Integer.valueOf(txtPort.getText()));
-					textPane.setText(textPane.getText() + "\n" + received);
+					textPane.setText(textPane.getText() + "\nPopped: "
+							+ received);
 				} catch (NumberFormatException e1) {
-					e1.printStackTrace();
-				} catch (IOException e2) {
-					e2.printStackTrace();
+					textPane.setText(textPane.getText()
+							+ "\nErroneous port number. " + e1.getMessage());
+				} catch (TimeoutException e2) {
+					textPane.setText(textPane.getText() + "\nServer timed out."
+							+ e2.getMessage());
+				} catch (IOException e1) {
+					textPane.setText(textPane.getText()
+							+ "\nCould not send to server. " + e1.getMessage());
 				}
-
-				textPane.setText(textPane.getText() + "\n" + received);
 			}
 		});
 		btnPush.addActionListener(new ActionListener() {
@@ -126,9 +132,15 @@ public class ClientGUI extends JFrame {
 					String host = txtHost.getText();
 					int port = Integer.valueOf(txtPort.getText());
 					client.push(userinput.getText(), host, port);
-				} catch (IOException e) {
-					// TODO Auto-generated catch block
-					e.printStackTrace();
+				} catch (NumberFormatException e1) {
+					textPane.setText(textPane.getText()
+							+ "\nErroneous port number. " + e1.getMessage());
+				} catch (IOException e1) {
+					textPane.setText(textPane.getText()
+							+ "\nCould not send to server. " + e1.getMessage());
+				} catch (TimeoutException e) {
+					textPane.setText(textPane.getText() + "\nServer timed out."
+							+ e.getMessage());
 				}
 			}
 		});
diff --git a/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/MessageType.java b/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/MessageType.java
new file mode 100644
index 00000000..17911086
--- /dev/null
+++ b/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/MessageType.java
@@ -0,0 +1,8 @@
+package buffered;
+
+public class MessageType {
+	protected static final byte CMD_PUSH = '0';
+	protected static final byte CMD_DATA = '1';
+	protected static final byte CMD_POP = '2';
+	protected static final byte CMD_PRINT = '3';
+}
diff --git a/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/TimeoutException.java b/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/TimeoutException.java
new file mode 100644
index 00000000..99da07b7
--- /dev/null
+++ b/ws2012/P2P/uebungen/2/p2p_ex2/src/buffered/TimeoutException.java
@@ -0,0 +1,7 @@
+package buffered;
+
+public class TimeoutException extends Exception {
+	public TimeoutException(String msg) {
+		super(msg);
+	}
+}