gistfile1.cs

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

public class serv
{
    public static void Main()
    {
        try
        {
            IPAddress ipAd = IPAddress.Parse("192.168.0.100");
            // use local m/c IP address, and 
            // use the same in the client

            /* Initializes the Listener */
            TcpListener myList = new TcpListener(ipAd, 8080);

            /* Start Listeneting at the specified port */
            myList.Start();

            Console.WriteLine("The server is running at port 8080...");
            Console.WriteLine("The local End point is  :" +
                              myList.LocalEndpoint);
            Console.WriteLine("Waiting for a connection.....");
            Socket s = myList.AcceptSocket();
            Console.WriteLine("Connection accepted from " + s.RemoteEndPoint);

            byte[] b = new byte[100];
            int k = s.Receive(b);
            Console.WriteLine("Recieved...");
            for (int i = 0; i < k; i++)
                Console.Write(Convert.ToChar(b[i]));

            ASCIIEncoding asen = new ASCIIEncoding();

            s.Send(asen.GetBytes(Console.ReadLine()));
            Console.WriteLine("\nSent Acknowledgement");
            s.Close();
            myList.Stop();
        }
        catch (Exception e)
        {
            Console.WriteLine("Error..... " + e.StackTrace);
        }
    }

}

gistfile2.cs

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


public class clnt
{

    public static void Main()
    {
        while (true)
        {

            try
            {
                TcpClient tcpclnt = new TcpClient();
                Console.WriteLine("Connecting.....");

                tcpclnt.Connect("192.168.0.100", 8080);
                // use the ipaddress as in the server program

                Console.WriteLine("Connected");
                Console.Write("Enter the string to be transmitted : ");

                String str = Console.ReadLine();
                Stream stm = tcpclnt.GetStream();

                ASCIIEncoding asen = new ASCIIEncoding();
                byte[] ba = asen.GetBytes(str);
                Console.WriteLine("Transmitting.....");

                stm.Write(ba, 0, ba.Length);

                byte[] bb = new byte[100];
                int k = stm.Read(bb, 0, 100);

                for (int i = 0; i < k; i++)
                    Console.Write(Convert.ToChar(bb[i]));

                tcpclnt.Close();
            }

            catch (Exception e)
            {
                Console.WriteLine("Error..... " + e.StackTrace);
            }
        }
    }

}