/// <summary>
            /// Starts operation processing.
            /// </summary>
            /// <param name="owner">Owner TCP client.</param>
            /// <returns>Returns true if asynchronous operation in progress or false if operation completed synchronously.</returns>
            /// <exception cref="ArgumentNullException">Is raised when <b>owner</b> is null reference.</exception>
            internal bool Start(TCP_Client owner)
            {
                if(owner == null){
                    throw new ArgumentNullException("owner");
                }

                m_pTcpClient = owner;

                SetState(AsyncOP_State.Active);

                try{
                    // Create socket.
                    if(m_pRemoteEP.AddressFamily == AddressFamily.InterNetwork){
                        m_pSocket = new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);
                        m_pSocket.ReceiveTimeout = m_pTcpClient.m_Timeout;
                        m_pSocket.SendTimeout = m_pTcpClient.m_Timeout;
                    }
                    else if(m_pRemoteEP.AddressFamily == AddressFamily.InterNetworkV6){
                        m_pSocket = new Socket(AddressFamily.InterNetworkV6,SocketType.Stream,ProtocolType.Tcp);
                        m_pSocket.ReceiveTimeout = m_pTcpClient.m_Timeout;
                        m_pSocket.SendTimeout = m_pTcpClient.m_Timeout;
                    }
                    // Bind socket to the specified end point.
                    if(m_pLocalEP != null){
                        m_pSocket.Bind(m_pLocalEP);
                    }

                    m_pTcpClient.LogAddText("Connecting to " + m_pRemoteEP.ToString() + ".");

                    // Start connecting.
                    m_pSocket.BeginConnect(m_pRemoteEP,this.BeginConnectCompleted,null);
                }
                catch(Exception x){
                    m_pException = x;
                    CleanupSocketRelated();
                    m_pTcpClient.LogAddException("Exception: " + x.Message,x);
                    SetState(AsyncOP_State.Completed);

                    return false;
                }

                // Set flag rise CompletedAsync event flag. The event is raised when async op completes.
                // If already completed sync, that flag has no effect.
                lock(m_pLock){
                    m_RiseCompleted = true;

                    return m_State == AsyncOP_State.Active;
                }
            }
            /// <summary>
            /// Starts operation processing.
            /// </summary>
            /// <param name="owner">Owner TCP client.</param>
            /// <returns>Returns true if asynchronous operation in progress or false if operation completed synchronously.</returns>
            /// <exception cref="ArgumentNullException">Is raised when <b>owner</b> is null reference.</exception>
            internal bool Start(TCP_Client owner)
            {
                if(owner == null){
                    throw new ArgumentNullException("owner");
                }

                m_pTcpClient = owner;

                try{
                    m_pSslStream = new SslStream(m_pTcpClient.m_pTcpStream.SourceStream,false,this.RemoteCertificateValidationCallback);
                    m_pSslStream.BeginAuthenticateAsClient("dummy",this.BeginAuthenticateAsClientCompleted,null);                  
                }
                catch(Exception x){
                    m_pException = x;
                    SetState(AsyncOP_State.Completed);
                }

                // NOTE: If operation completed synchronously, then this.State is AsyncOP_State.Completed and we don't have pending operation.
                return this.State != AsyncOP_State.Completed;
            }
            /// <summary>
            /// Cleans up any resource being used.
            /// </summary>
            public void Dispose()
            {
                if(m_State == AsyncOP_State.Disposed){
                    return;
                }
                SetState(AsyncOP_State.Disposed);

                m_pException    = null;
                m_pLocalEP      = null;
                m_pRemoteEP     = null;
                m_SSL           = false;
                m_pCertCallback = null;
                m_pTcpClient    = null;
                m_pSocket       = null;
                m_pStream       = null;

                this.CompletedAsync = null;
            }