using System;
using System.Net;
using System.Net.Sockets;
using System.Text;

public class Broadcst
{
    public static void Main()
    {
        Socket sock = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

        int portnumber = 9050;



            IPEndPoint iep1 = new IPEndPoint(IPAddress.Broadcast, portnumber);

            IPEndPoint iep2 = new IPEndPoint(IPAddress.Parse("192.168.1.255"), portnumber);

            string hostname = Dns.GetHostName();
            byte[] data = Encoding.ASCII.GetBytes(hostname);

            sock.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.Broadcast, 1);
            sock.SendTo(data, iep1);
            sock.SendTo(data, iep2);

           // portnumber--;
            sock.Close();
    }
}

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;

public class RecvBroadcst
{
    public static void Main()
    {
       Socket sock = new Socket(AddressFamily.InterNetwork,
                           SocketType.Dgram, ProtocolType.Udp);
     //  int port_no=Convert.ToInt32(sock.RemoteEndPoint);


         int portnumber = 9050;

            sock = new Socket(AddressFamily.InterNetwork,
                           SocketType.Dgram, ProtocolType.Udp);
            IPEndPoint iep = new IPEndPoint(IPAddress.Any,portnumber);
            sock.Bind(iep);
            EndPoint ep = (EndPoint)iep;
            Console.WriteLine("Ready to receive...");
          // int port_no = Convert.ToInt32(sock.RemoteEndPoint);
            while (true)
            {

                byte[] data = new byte[1024];
                int recv = sock.ReceiveFrom(data, ref ep);
                string stringData = Encoding.ASCII.GetString(data, 0, recv);
                Console.WriteLine("received: {0}  from: {1}",
                                      stringData, ep.ToString());

                //data = new byte[1024];
                //recv = sock.ReceiveFrom(data, ref ep);
                //stringData = Encoding.ASCII.GetString(data, 0, recv);
                //Console.WriteLine("received: {0}  from: {1}",
                //                      stringData, ep.ToString());

                data = null;
            }
            //portnumber--;


        sock.Close();
    }
}