--- a/net/minecraft/server/network/ServerHandshakePacketListenerImpl.java
+++ b/net/minecraft/server/network/ServerHandshakePacketListenerImpl.java
@@ -11,8 +11,17 @@
 import net.minecraft.network.protocol.status.ServerStatus;
 import net.minecraft.server.MinecraftServer;
 
+// CraftBukkit start
+import java.net.InetAddress;
+import java.util.HashMap;
+// CraftBukkit end
+
 public class ServerHandshakePacketListenerImpl implements ServerHandshakePacketListener {
 
+    // CraftBukkit start - add fields
+    private static final HashMap<InetAddress, Long> throttleTracker = new HashMap<InetAddress, Long>();
+    private static int throttleCounter = 0;
+    // CraftBukkit end
     private static final Component IGNORE_STATUS_REASON = Component.translatable("disconnect.ignoring_status_request");
     private final MinecraftServer server;
     private final Connection connection;
@@ -23,16 +32,50 @@
     }
 
     @Override
-    @Override
-    public void handleIntention(ClientIntentionPacket clientintentionpacket) {
-        switch (clientintentionpacket.intention()) {
+    public void handleIntention(ClientIntentionPacket packet) {
+        this.connection.hostname = packet.hostName() + ":" + packet.port(); // CraftBukkit  - set hostname
+        switch (packet.intention()) {
             case LOGIN:
                 this.connection.setClientboundProtocolAfterHandshake(ClientIntent.LOGIN);
-                if (clientintentionpacket.protocolVersion() != SharedConstants.getCurrentVersion().getProtocolVersion()) {
-                    MutableComponent mutablecomponent;
+                // CraftBukkit start - Connection throttle
+                try {
+                    long currentTime = System.currentTimeMillis();
+                    long connectionThrottle = this.server.server.getConnectionThrottle();
+                    InetAddress address = ((java.net.InetSocketAddress) this.connection.getRemoteAddress()).getAddress();
 
-                    if (clientintentionpacket.protocolVersion() < 754) {
-                        mutablecomponent = Component.translatable("multiplayer.disconnect.outdated_client", SharedConstants.getCurrentVersion().getName());
+                    synchronized (throttleTracker) {
+                        if (throttleTracker.containsKey(address) && !"127.0.0.1".equals(address.getHostAddress()) && currentTime - throttleTracker.get(address) < connectionThrottle) {
+                            throttleTracker.put(address, currentTime);
+                            MutableComponent chatmessage = Component.literal("Connection throttled! Please wait before reconnecting.");
+                            this.connection.send(new ClientboundLoginDisconnectPacket(chatmessage));
+                            this.connection.disconnect(chatmessage);
+                            return;
+                        }
+
+                        throttleTracker.put(address, currentTime);
+                        throttleCounter++;
+                        if (throttleCounter > 200) {
+                            throttleCounter = 0;
+
+                            // Cleanup stale entries
+                            java.util.Iterator iter = throttleTracker.entrySet().iterator();
+                            while (iter.hasNext()) {
+                                java.util.Map.Entry<InetAddress, Long> entry = (java.util.Map.Entry) iter.next();
+                                if (entry.getValue() > connectionThrottle) {
+                                    iter.remove();
+                                }
+                            }
+                        }
+                    }
+                } catch (Throwable t) {
+                    org.apache.logging.log4j.LogManager.getLogger().debug("Failed to check connection throttle", t);
+                }
+                // CraftBukkit end
+                if (packet.protocolVersion() != SharedConstants.getCurrentVersion().getProtocolVersion()) {
+                    MutableComponent ichatmutablecomponent;
+
+                    if (packet.protocolVersion() < 754) {
+                        ichatmutablecomponent = Component.translatable("multiplayer.disconnect.outdated_client", SharedConstants.getCurrentVersion().getName());
                     } else {
                         mutablecomponent = Component.translatable("multiplayer.disconnect.incompatible", SharedConstants.getCurrentVersion().getName());
                     }