diff --git a/src/PamController/PamController.java b/src/PamController/PamController.java
index 227dbdaf..611dd9a2 100644
--- a/src/PamController/PamController.java
+++ b/src/PamController/PamController.java
@@ -55,6 +55,7 @@ import generalDatabase.DBControlUnit;
 import javafx.application.Platform;
 import javafx.stage.Stage;
 import Array.ArrayManager;
+import PamController.command.MultiportController;
 import PamController.command.NetworkController;
 import PamController.command.TerminalController;
 import PamController.command.WatchdogComms;
@@ -255,6 +256,9 @@ public class PamController implements PamControllerInterface, PamSettings {
 		if (pamBuoyGlobals.getNetworkControlPort() != null) {
 			networkController = new NetworkController(this);
 		}
+		if (pamBuoyGlobals.getMultiportAddress() != null) {
+			new MultiportController(this);
+		}
 
 		
 		//		binaryStore = new BinaryStore(this);
diff --git a/src/PamController/command/MultiportController.java b/src/PamController/command/MultiportController.java
new file mode 100644
index 00000000..ead9e397
--- /dev/null
+++ b/src/PamController/command/MultiportController.java
@@ -0,0 +1,118 @@
+package PamController.command;
+
+import java.io.IOException;
+import java.net.DatagramPacket;
+import java.net.DatagramSocket;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.MulticastSocket;
+import java.net.NetworkInterface;
+import java.net.SocketAddress;
+import java.nio.charset.StandardCharsets;
+
+import PamController.PamController;
+import PamController.pamBuoyGlobals;
+
+public class MultiportController extends CommandManager {
+	
+	//The multicast addresses are in the range 224.0.0.0 through 239.255.255.255
+
+	private static String unitName = "Multiport Controller";
+	private PamController pamController;
+	private String mAddress;
+	private int mPort;
+	private MulticastSocket socket;
+	InetAddress inetAddr;
+
+	static private final int MAX_COMMAND_LENGTH = 4096;
+	
+	private byte[] byteBuffer = new byte[MAX_COMMAND_LENGTH];
+	private DatagramPacket lastDatagram;
+
+	public MultiportController(PamController pamController) {
+		super(pamController, unitName);
+		this.pamController = pamController;
+		this.mAddress = pamBuoyGlobals.getMultiportAddress();
+		this.mPort = pamBuoyGlobals.getMuliportPort();
+		
+		Thread t = new Thread(new ListenerThread());
+		t.start();
+	}
+
+	public void runListenerLoop() {
+		try {
+			//			inetAddr = InetAddress.getByName(mAddress);
+			//			SocketAddress sockAddr = new SocketAddress() 
+			//			socket = new MulticastSocket(mPort);
+			//			socket.joinGroup(inetAddr, null);
+			//			socket.joinG
+
+			// open port
+			InetAddress mcastaddr = InetAddress.getByName(mAddress);
+			InetSocketAddress group = new InetSocketAddress(mcastaddr, mPort);
+			NetworkInterface netIf = NetworkInterface.getByName("bge0");
+			socket = new MulticastSocket(mPort);
+			socket.joinGroup(group, netIf);
+			socket.setSoTimeout(0);
+
+			System.out.printf("Waiting for multicast messages at %s port %d\n", mAddress, mPort);
+
+			//  sit in loop
+			while (true) {
+				try {
+					DatagramPacket datagram = new DatagramPacket(byteBuffer, MAX_COMMAND_LENGTH);
+					socket.receive(datagram);
+					processDatagram(datagram);
+				}
+				catch (IOException ioE) {
+					ioE.printStackTrace();
+					break;
+				}
+			}
+
+			// close port.
+
+			socket.leaveGroup(group, netIf);
+		}
+		catch(Exception e)
+		{
+			e.printStackTrace();
+		}
+	}
+
+	private void processDatagram(DatagramPacket datagram) {
+		lastDatagram = datagram;
+		String str = new String(datagram.getData(), 0, datagram.getLength());
+//		str = str.substring(0, datagram.getLength());
+		System.out.println("Datagram received \"" + str + "\"");
+		interpretCommand(str);
+	}
+
+	@Override
+	public boolean sendData(String dataString) {
+		DatagramPacket senderInfo = lastDatagram;
+		System.out.printf("Send back data \"%s\" to %s port %d\n", dataString, senderInfo.getAddress(), senderInfo.getPort());
+//		dataString += "\n";
+		DatagramPacket packet = new DatagramPacket(dataString.getBytes(), dataString.length());
+		packet.setAddress(senderInfo.getAddress());
+		packet.setPort(senderInfo.getPort());
+		try {
+			socket.send(packet);
+//			receiveSocket.
+		} catch (IOException e) {
+			// TODO Auto-generated catch block
+			e.printStackTrace();
+			return false;
+		}
+		return true;
+	}
+
+	private class ListenerThread implements Runnable {
+
+		@Override
+		public void run() {
+			runListenerLoop();
+		}
+
+	}
+}
diff --git a/src/PamController/pamBuoyGlobals.java b/src/PamController/pamBuoyGlobals.java
index 26cc5a90..dee3a1db 100644
--- a/src/PamController/pamBuoyGlobals.java
+++ b/src/PamController/pamBuoyGlobals.java
@@ -14,7 +14,9 @@ public class pamBuoyGlobals {
 //	public static Integer useGstreamer     = 0;
 //	public static boolean useNetworkCont   = false;
 	private static Integer networkControlPort = null;
+private static String multiportAddress;
 //	private static boolean useDSP = false;
+private static int muliportPort;
 
 	/**
 	 * @return the networkControlPort
@@ -29,6 +31,31 @@ public class pamBuoyGlobals {
 	public static void setNetworkControlPort(Integer networkControlPort) {
 		pamBuoyGlobals.networkControlPort = networkControlPort;
 	}
+
+	/**
+	 * Set parameters for mulitport configutation.
+	 * @param mAddr
+	 * @param mPort
+	 */
+	public static void setMultiportConfig(String mAddr, int mPort) {
+		multiportAddress = mAddr;
+		muliportPort = mPort;
+		
+	}
+
+	/**
+	 * @return the multiportAddress
+	 */
+	public static String getMultiportAddress() {
+		return multiportAddress;
+	}
+
+	/**
+	 * @return the muliportPort
+	 */
+	public static int getMuliportPort() {
+		return muliportPort;
+	}
 	
 
 	//public static HashMap pbHash = new HashMap(10,0.75);
diff --git a/src/pamguard/GlobalArguments.java b/src/pamguard/GlobalArguments.java
index c8c6599a..4f601911 100644
--- a/src/pamguard/GlobalArguments.java
+++ b/src/pamguard/GlobalArguments.java
@@ -24,10 +24,23 @@ public class GlobalArguments {
 	/**
 	 * Get a global parameter value
 	 * @param name value name
-	 * @return value
+	 * @return value in original String format
 	 */
 	public static String getParam(String name) {
 		return globalFlags.get(name);
 	}
 	
+	/**
+	 * Get a param read as an integer
+	 * @param name
+	 * @return value as integer or null if not set. Throws exception if invalid integer. 
+	 */
+	public static Integer getParamI(String name) {
+		String val = getParam(name);
+		if (val == null) {
+			return null;
+		}
+		return Integer.valueOf(val);
+	}
+	
 }
diff --git a/src/pamguard/Pamguard.java b/src/pamguard/Pamguard.java
index f1f7aaa1..c955192a 100644
--- a/src/pamguard/Pamguard.java
+++ b/src/pamguard/Pamguard.java
@@ -212,8 +212,15 @@ public class Pamguard {
 					System.out.println("Running using settings from " + autoPsf);
 				}
 				else if (anArg.equalsIgnoreCase("-port")) {
+					// port id to open a udp port to receive commands
 					pamBuoyGlobals.setNetworkControlPort(Integer.parseInt(args[iArg++]));
 				}
+				else if (anArg.equalsIgnoreCase("-mport")) {
+					// multicast control (for multiple PAMGuards) 
+					String mAddr = args[iArg++];
+					int mPort = Integer.parseInt(args[iArg++]);
+					pamBuoyGlobals.setMultiportConfig(mAddr, mPort);
+				}
 				else if (anArg.equalsIgnoreCase("-nolog")) {
 					System.out.println("Disabling log file from command line switch...");
 					ProxyPrintStream.disableLogFile();