ForeignAgent.java

import java.io.*;
import java.net.*;
import java.util.*;

public class ForeignAgent
    {
    public static void main(String[] args) throws Exception
        {
        /* creates a socket with the local broadcast address, 192.168.1.255 */
        DatagramSocket broadcastSocket = new DatagramSocket();
        InetAddress broadcastIP = InetAddress.getByName("192.168.1.255");
        InetAddress myIP = InetAddress.getByName("hostid");
        byte[] data;
        /* encapsulates a message in "data" containing myIP and a message that means the unit is available to serve as a foreign agent */
        /* sends the message */
        DatagramPacket packet = new DatagramPacket (data, data.length, broadcastIP, 8001);
        broadcastSocket.send(packet);
        /* performs other functions */

        broadcastSocket.close();
        }
    }