multicast problems

[Daniil Sosonkin]

Hello, I have two small programs, one server that sends out messages and clients that receive it. Server runs on Linux with two (2) NICs and broadcasts. I've set it to broadcast to 192.168.110.255:6666 and then client joins 230.0.0.1:6666. Otherwise nothing is being received. So the problem is that this client receives one packet twice. Maybe I'm doing something totally wrong. I'd really appreciate if someone took a look at simple code below and point it where its wrong cause I'm totally lost. Btw, if I set server to broadcast to 230.0.0.1:6666 then client receives nothing.

The server:

import java.io.*;
import java.net.*;
import java.util.*;
 
public class MulticastServer
{
        public static void main(String[] args) throws Exception
        {
                int port = 6666;
                InetAddress group = InetAddress.getByName("192.168.110.255");
                MulticastSocket soc = new MulticastSocket(port);
 
                System.out.println(group);
                while (true)
                {
                        byte[] buf = new Date().toString().getBytes();
 
                        DatagramPacket packet = new DatagramPacket(buf, buf.length, group, port);
                        soc.send(packet);
                        System.out.println("Sent: " + new String(buf));
 
                        Thread.sleep(1000);
                }
        }
}

The client:

package com;
 
import java.net.*;
 
public class Test
    {
        public static void main(String[] args) throws Exception
            {
                MulticastSocket socket = new MulticastSocket(6666);
                socket.joinGroup(InetAddress.getByName("230.0.0.1"));
 
                int  i =0;
                while (true)
                    {
                        byte[] buf = new byte[1024 * 46];
                        DatagramPacket packet = new DatagramPacket(buf, buf.length);
                        socket.receive(packet);
 
                        System.out.println((i++) + ") " + new String(packet.getData(), packet.getOffset(), packet.getLength()));
                        System.out.println("Address: " + packet.getSocketAddress());
                    }
            }
    }

[ November 12, 2004: Message edited by: Daniil Sosonkin ]