/// <summary>
        /// Attaches a tracer to this connection. Only allowed in state 'Initializing'. To avoid race conditions,
        /// this method should only be used  in conjunction with the parameterless constructor (no auto-connect).
        /// Call this method *before* calling Connect.
        /// </summary>
        /// <param name="tracer">Tracer to attach</param>
        /// <exception cref="ArgumentNullException"><paramref name="tracer"/> is null</exception>
        /// <exception cref="InvalidOperationException">Connection is not in state 'Initializing'</exception>
        public void AttachTracer(IFrameTracer tracer)
        {
            if (tracer == null)
            {
                throw new ArgumentNullException(nameof(tracer));
            }

            if (State != ConnectionState.Initializing)
            {
                throw new InvalidOperationException("Connection is not in state 'Initializing'");
            }

            _attachTracerAction += () =>
            {
                _pump?.AttachTracer(tracer);
            };
        }
            public void Start()
            {
                Pump = new FramePump(_stream);

                foreach (var tracer in _tracers)
                {
                    Pump.AttachTracer(tracer);
                }
                _tracers.Clear();

                OutboundEp          = new OutboundTcpEndpoint(_server, Pump);
                InboundEp           = _server._rpcEngine.AddEndpoint(OutboundEp);
                Pump.FrameReceived += InboundEp.Forward;

                State = ConnectionState.Active;

                PumpRunner = new Thread(o =>
                {
                    try
                    {
                        Thread.CurrentThread.Name = $"TCP RPC Server Thread {Thread.CurrentThread.ManagedThreadId}";

                        Pump.Run();
                    }
                    catch (ThreadInterruptedException)
                    {
                        Logger.LogError($"{Thread.CurrentThread.Name} interrupted at {Environment.StackTrace}");
                    }
                    finally
                    {
                        OutboundEp.Dismiss();
                        InboundEp.Dismiss();
                        Pump.Dispose();
                        Client.Dispose();
                        lock (_server._reentrancyBlocker)
                        {
                            --_server.ConnectionCount;
                            _server._connections.Remove(this);
                            State = ConnectionState.Down;
                            _server.OnConnectionChanged?.Invoke(_server, new ConnectionEventArgs(this));
                        }
                    }
                });
                PumpRunner.Start();
            }