diff --git a/src/com/captainalm/lib/calmnet/marshal/NetMarshalClient.java b/src/com/captainalm/lib/calmnet/marshal/NetMarshalClient.java
index 86c43b2..8827fde 100644
--- a/src/com/captainalm/lib/calmnet/marshal/NetMarshalClient.java
+++ b/src/com/captainalm/lib/calmnet/marshal/NetMarshalClient.java
@@ -64,6 +64,7 @@ public class NetMarshalClient implements Closeable {
     protected final Thread fragmentMonitorThread;
     protected final Thread fragmentFinishReceiveMonitorThread;
     protected final Thread fragmentFinishSendMonitorThread;
+    protected final Thread fragmentSendThread;
 
     private NetMarshalClient(InetAddress remoteAddress, int remotePort, IPacketFactory factory, PacketLoader loader, boolean isMulticast, boolean isSocketNull, FragmentationOptions fragmentationOptions) {
         if (isSocketNull) throw new NullPointerException("socketIn is null");
@@ -85,6 +86,7 @@ public class NetMarshalClient implements Closeable {
             fragmentMonitorThread = null;
             fragmentFinishReceiveMonitorThread = null;
             fragmentFinishSendMonitorThread = null;
+            fragmentSendThread = null;
             receiveThread = new Thread(() -> {
                 while (running) receiveThreadExecuted();
             }, "thread_receive_" + remoteAddress.getHostAddress() + ":" + remotePort);
@@ -148,6 +150,28 @@ public class NetMarshalClient implements Closeable {
                 }
                 fragmentSender.clearLastIDFinished();
             }, "thread_frag_fin_send_monitor_" + remoteAddress.getHostAddress() + ":" + remotePort);
+            fragmentSendThread = new Thread(() -> {
+                while (running) {
+                    try {
+                        synchronized (slocksock) {
+                            slocksock.wait();
+                            IPacket[] packets = fragmentSender.sendPacket();
+                            for (IPacket c : packets) if (c != null) {
+                                updateMState(fragmentSMM, c);
+                                loader.writePacket(outputStream, c, true);
+                            }
+                            packets = fragmentReceiver.sendPacket();
+                            for (IPacket c : packets) if (c != null) {
+                                updateMState(fragmentRMM, c);
+                                loader.writePacket(outputStream, c, true);
+                            }
+                        }
+                    } catch (InterruptedException e) {
+                    } catch (IOException | PacketException e) {
+                        if (receiveExceptionBiConsumer != null) receiveExceptionBiConsumer.accept(e, this);
+                    }
+                }
+            }, "thread_frag_send_" + remoteAddress.getHostAddress() + ":" + remotePort);
             receiveThread = new Thread(() -> {
                 while (running) receiveThreadExecutedWithFragmentation();
                 fragmentReceiver.clearWaitingPackets();
@@ -234,19 +258,6 @@ public class NetMarshalClient implements Closeable {
         }
     }
 
-    protected void sendFragmentData() throws PacketException, IOException {
-        IPacket[] packets = fragmentSender.sendPacket();
-        for (IPacket c : packets) if (c != null) {
-            updateMState(fragmentSMM, c);
-            loader.writePacket(outputStream, c, true);
-        }
-        packets = fragmentReceiver.sendPacket();
-        for (IPacket c : packets) if (c != null) {
-            updateMState(fragmentRMM, c);
-            loader.writePacket(outputStream, c, true);
-        }
-    }
-
     /**
      * Opens the marshal.
      */
@@ -257,6 +268,7 @@ public class NetMarshalClient implements Closeable {
             fragmentMonitorThread.start();
             fragmentFinishReceiveMonitorThread.start();
             fragmentFinishSendMonitorThread.start();
+            fragmentSendThread.start();
         }
         receiveThread.start();
     }
@@ -397,15 +409,17 @@ public class NetMarshalClient implements Closeable {
      * @throws IOException A stream exception has occurred.
      * @throws PacketException An exception has occurred.
      * @throws NullPointerException packetIn is null.
+     * @throws IllegalStateException sendPacket accessed in the receive thread.
      */
     public final void sendPacket(IPacket packetIn, boolean directSend) throws IOException, PacketException {
         if (packetIn == null) throw new NullPointerException("packetIn is null");
+        if (Thread.currentThread() == receiveThread) throw new IllegalStateException("sendPacket accessed in the receive thread");
         synchronized (slocksock) {
             if (fragmentationOptions == null || directSend) {
                 loader.writePacket(outputStream, packetIn, true);
             } else {
                 fragmentSender.sendPacket(packetIn);
-                sendFragmentData();
+                slocksock.notifyAll();
             }
         }
     }
@@ -414,8 +428,10 @@ public class NetMarshalClient implements Closeable {
      * Flushes the output streams.
      *
      * @throws IOException A stream exception has occurred.
+     * @throws IllegalStateException flush accessed in the receive thread.
      */
     public final void flush() throws IOException {
+        if (Thread.currentThread() == receiveThread) throw new IllegalStateException("sendPacket accessed in the receive thread");
         synchronized (slocksock) {
             outputStream.flush();
             rootOutputStream.flush();
@@ -542,6 +558,7 @@ public class NetMarshalClient implements Closeable {
 
     /**
      * Gets the {@link BiConsumer} receiver consumer.
+     * WARNING: {@link #sendPacket(IPacket, boolean)} and {@link #flush()} cannot be called within the consumer.
      *
      * @return The receiver consumer or null.
      */
@@ -551,6 +568,7 @@ public class NetMarshalClient implements Closeable {
 
     /**
      * Sets the {@link BiConsumer} receiver consumer.
+     * WARNING: {@link #sendPacket(IPacket, boolean)} and {@link #flush()} cannot be called within the consumer.
      *
      * @param consumer The new receiver consumer.
      * @throws NullPointerException consumer is null.
@@ -614,6 +632,7 @@ public class NetMarshalClient implements Closeable {
                 fragmentMonitorThread.interrupt();
                 fragmentFinishReceiveMonitorThread.interrupt();
                 fragmentFinishSendMonitorThread.interrupt();
+                fragmentSendThread.interrupt();
             }
             receivedPackets.clear();
             synchronized (slockReceive) {
@@ -681,7 +700,7 @@ public class NetMarshalClient implements Closeable {
                         }
                     }
                     synchronized (slocksock) {
-                        sendFragmentData();
+                        slocksock.notifyAll();
                     }
                 } else {
                     if (receiveBiConsumer != null) receiveBiConsumer.accept(packet, this);
diff --git a/src/com/captainalm/lib/calmnet/marshal/NetMarshalServer.java b/src/com/captainalm/lib/calmnet/marshal/NetMarshalServer.java
index ff9cab0..5d01821 100644
--- a/src/com/captainalm/lib/calmnet/marshal/NetMarshalServer.java
+++ b/src/com/captainalm/lib/calmnet/marshal/NetMarshalServer.java
@@ -194,6 +194,7 @@ public class NetMarshalServer implements Closeable {
      * @throws IOException A stream exception has occurred.
      * @throws PacketException An exception has occurred.
      * @throws NullPointerException packetIn is null.
+     * @throws IllegalStateException sendPacket accessed in the receive thread.
      */
     public final void broadcastPacket(IPacket packetIn, boolean directSend) throws IOException, PacketException {
         if (packetIn == null) throw new NullPointerException("packetIn is null");
@@ -207,6 +208,7 @@ public class NetMarshalServer implements Closeable {
      * Flushes all the output streams on all the clients.
      *
      * @throws IOException A stream exception has occurred.
+     * @throws IllegalStateException flush accessed in the receive thread.
      */
     public final void flush() throws IOException {
         synchronized (slocksock) {
@@ -226,6 +228,7 @@ public class NetMarshalServer implements Closeable {
 
     /**
      * Gets the {@link BiConsumer} receiver consumer.
+     * WARNING: {@link #broadcastPacket(IPacket, boolean)} and {@link #flush()} cannot be called within the consumer.
      *
      * @return The receiver consumer or null.
      */
@@ -235,6 +238,7 @@ public class NetMarshalServer implements Closeable {
 
     /**
      * Sets the {@link BiConsumer} receiver consumer.
+     * WARNING: {@link #broadcastPacket(IPacket, boolean)} and {@link #flush()} cannot be called within the consumer.
      *
      * @param consumer The new receiver consumer.
      * @throws NullPointerException consumer is null.