# 체크 메소드

private static bool ConnectTest(string ip, int port) {
            bool result = false;
            Socket socket = null;
            try {
                socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
                socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.DontLinger, false);
                IAsyncResult ret = socket.BeginConnect(ip, port, null, null);
                result = ret.AsyncWaitHandle.WaitOne(100, true);
            }
            catch (Exception e)
            {
                System.Console.WriteLine(e);
            }
            finally
            {
                if (socket != null) {
                    socket.Close();
                }
            }
            return result;
        }