diff --git a/core/gen/com/riiablo/net/packet/d2gs/Ping.java b/core/gen/com/riiablo/net/packet/d2gs/Ping.java
index 1bf7cf17..84a94d11 100644
--- a/core/gen/com/riiablo/net/packet/d2gs/Ping.java
+++ b/core/gen/com/riiablo/net/packet/d2gs/Ping.java
@@ -17,22 +17,26 @@ public final class Ping extends Table {
   public int tickCount() { int o = __offset(4); return o != 0 ? bb.getInt(o + bb_pos) : 0; }
   public long sendTime() { int o = __offset(6); return o != 0 ? bb.getLong(o + bb_pos) : 0L; }
   public long processTime() { int o = __offset(8); return o != 0 ? bb.getLong(o + bb_pos) : 0L; }
+  public boolean ack() { int o = __offset(10); return o != 0 ? 0!=bb.get(o + bb_pos) : false; }
 
   public static int createPing(FlatBufferBuilder builder,
       int tickCount,
       long sendTime,
-      long processTime) {
-    builder.startObject(3);
+      long processTime,
+      boolean ack) {
+    builder.startObject(4);
     Ping.addProcessTime(builder, processTime);
     Ping.addSendTime(builder, sendTime);
     Ping.addTickCount(builder, tickCount);
+    Ping.addAck(builder, ack);
     return Ping.endPing(builder);
   }
 
-  public static void startPing(FlatBufferBuilder builder) { builder.startObject(3); }
+  public static void startPing(FlatBufferBuilder builder) { builder.startObject(4); }
   public static void addTickCount(FlatBufferBuilder builder, int tickCount) { builder.addInt(0, tickCount, 0); }
   public static void addSendTime(FlatBufferBuilder builder, long sendTime) { builder.addLong(1, sendTime, 0L); }
   public static void addProcessTime(FlatBufferBuilder builder, long processTime) { builder.addLong(2, processTime, 0L); }
+  public static void addAck(FlatBufferBuilder builder, boolean ack) { builder.addBoolean(3, ack, false); }
   public static int endPing(FlatBufferBuilder builder) {
     int o = builder.endObject();
     return o;
diff --git a/core/src/com/riiablo/engine/client/NetworkProfiler.java b/core/src/com/riiablo/engine/client/NetworkProfiler.java
index 088fffef..360068e3 100644
--- a/core/src/com/riiablo/engine/client/NetworkProfiler.java
+++ b/core/src/com/riiablo/engine/client/NetworkProfiler.java
@@ -49,8 +49,11 @@ public class NetworkProfiler extends IntervalBaseSystem implements Pinger.Packet
   }
 
   @Override
-  public void onPingResponse(Pinger pinger, Ping packet, long ping, long rtt) {
-    this.ping = ping;
-    this.rtt = rtt;
+  public void onPingResponse(Pinger pinger, Ping packet, long ping, long rtt, boolean ack) {
+    if (ack){
+      this.ping = ping;
+    } else {
+      this.rtt = rtt;
+    }
   }
 }
diff --git a/core/src/com/riiablo/engine/client/Pinger.java b/core/src/com/riiablo/engine/client/Pinger.java
index 8b79d933..220fb366 100644
--- a/core/src/com/riiablo/engine/client/Pinger.java
+++ b/core/src/com/riiablo/engine/client/Pinger.java
@@ -30,8 +30,8 @@ public class Pinger extends IntervalBaseSystem {
   //       it may be possible to use Gdx.graphics.getFrameId() -- but that isn't related to engine tick
   private int tick;
 
-  public long ping;
-  public long rtt;
+  private long ping;
+  private long rtt;
 
   public Pinger() {
     super(1.0f);
@@ -40,7 +40,7 @@ public class Pinger extends IntervalBaseSystem {
   @Override
   protected void processSystem() {
     FlatBufferBuilder builder = new FlatBufferBuilder(0);
-    int dataOffset = Ping.createPing(builder, tick++, TimeUtils.millis(), 0);
+    int dataOffset = Ping.createPing(builder, tick++, TimeUtils.millis(), 0, false);
     int root = D2GS.createD2GS(builder, D2GSData.Ping, dataOffset);
     D2GS.finishSizePrefixedD2GSBuffer(builder, root);
 
@@ -65,10 +65,11 @@ public class Pinger extends IntervalBaseSystem {
   }
 
   private void notifyPing(Ping packet, long ping, long rtt) {
-    for (PacketListener l : packetListeners) l.onPingResponse(this, packet, ping, rtt);
+    boolean ack = packet.ack();
+    for (PacketListener l : packetListeners) l.onPingResponse(this, packet, ping, rtt, ack);
   }
 
   public interface PacketListener {
-    void onPingResponse(Pinger pinger, Ping packet, long ping, long rtt);
+    void onPingResponse(Pinger pinger, Ping packet, long ping, long rtt, boolean ack);
   }
 }
diff --git a/core/src/com/riiablo/net/d2gs/Networking.fbs b/core/src/com/riiablo/net/d2gs/Networking.fbs
index 9c37bbde..49b0e608 100644
--- a/core/src/com/riiablo/net/d2gs/Networking.fbs
+++ b/core/src/com/riiablo/net/d2gs/Networking.fbs
@@ -27,4 +27,5 @@ table Ping {
   processTime:int64;
 
   // response
+  ack:bool;
 }
\ No newline at end of file
diff --git a/server/d2gs/src/com/riiablo/server/d2gs/D2GS.java b/server/d2gs/src/com/riiablo/server/d2gs/D2GS.java
index 3831351a..7782501f 100644
--- a/server/d2gs/src/com/riiablo/server/d2gs/D2GS.java
+++ b/server/d2gs/src/com/riiablo/server/d2gs/D2GS.java
@@ -537,7 +537,7 @@ public class D2GS extends ApplicationAdapter {
   private void Ping(Packet packet) {
     Ping ping = (Ping) packet.data.data(new Ping());
     FlatBufferBuilder builder = new FlatBufferBuilder(0);
-    int dataOffset = Ping.createPing(builder, ping.tickCount(), ping.sendTime(), TimeUtils.millis() - packet.time);
+    int dataOffset = Ping.createPing(builder, ping.tickCount(), ping.sendTime(), TimeUtils.millis() - packet.time, false);
     int root = com.riiablo.net.packet.d2gs.D2GS.createD2GS(builder, D2GSData.Ping, dataOffset);
     com.riiablo.net.packet.d2gs.D2GS.finishSizePrefixedD2GSBuffer(builder, root);
     Packet response = Packet.obtain(1 << packet.id, builder.dataBuffer());
@@ -706,6 +706,19 @@ public class D2GS extends ApplicationAdapter {
           if (!success) {
             Gdx.app.log(TAG, "failed to add to queue -- closing " + socket.getRemoteAddress());
             kill = true;
+          } else if (packet.data.dataType() == D2GSData.Ping) {
+            try {
+              Ping ping = (Ping) packet.data.data(new Ping());
+              FlatBufferBuilder builder = new FlatBufferBuilder(0);
+              int dataOffset = Ping.createPing(builder, ping.tickCount(), ping.sendTime(), 0, true);
+              int root = com.riiablo.net.packet.d2gs.D2GS.createD2GS(builder, D2GSData.Ping, dataOffset);
+              com.riiablo.net.packet.d2gs.D2GS.finishSizePrefixedD2GSBuffer(builder, root);
+              Packet response = Packet.obtain(1 << packet.id, builder.dataBuffer());
+              if (DEBUG_SENT_PACKETS && !ignoredPackets.get(packet.data.dataType())) Gdx.app.log(TAG, "dispatching " + D2GSData.name(packet.data.dataType()) + " ACK packet to " + String.format("0x%08X", packet.id));
+              send(response);
+            } catch (Throwable t) {
+              Gdx.app.log(TAG, t.getMessage(), t);
+            }
           }
         } catch (Throwable t) {
           Gdx.app.log(TAG, t.getMessage(), t);