diff --git a/utils/netty/src/main/java/org/onlab/netty/MessageDecoder.java b/utils/netty/src/main/java/org/onlab/netty/MessageDecoder.java
index 7997ef0..3ed3216 100644
--- a/utils/netty/src/main/java/org/onlab/netty/MessageDecoder.java
+++ b/utils/netty/src/main/java/org/onlab/netty/MessageDecoder.java
@@ -8,13 +8,18 @@
 import java.util.Arrays;
 import java.util.List;
 
-// TODO: Implement performance enchancements such as those described in the javadoc for ReplayingDecoder.
-public class MessageDecoder extends ReplayingDecoder<InternalMessage> {
+/**
+ * Decoder for inbound messages.
+ */
+public class MessageDecoder extends ReplayingDecoder<DecoderState> {
 
     private final NettyMessagingService messagingService;
     private final Serializer serializer;
 
+    private int contentLength;
+
     public MessageDecoder(NettyMessagingService messagingService, Serializer serializer) {
+        super(DecoderState.READ_HEADER_VERSION);
         this.messagingService = messagingService;
         this.serializer = serializer;
     }
@@ -25,16 +30,31 @@
             ByteBuf buffer,
             List<Object> out) throws Exception {
 
-        byte[] preamble = new byte[MessageEncoder.PREAMBLE.length];
-        buffer.readBytes(preamble);
-        checkState(Arrays.equals(MessageEncoder.PREAMBLE, preamble), "Message has wrong preamble");
-
-        int bodySize = buffer.readInt();
-        byte[] body = new byte[bodySize];
-        buffer.readBytes(body);
-
-        InternalMessage message = serializer.decode(body);
-        message.setMessagingService(messagingService);
-        out.add(message);
+        switch(state()) {
+        case READ_HEADER_VERSION:
+            int headerVersion = buffer.readInt();
+            checkState(headerVersion == MessageEncoder.HEADER_VERSION, "Unexpected header version");
+            checkpoint(DecoderState.READ_PREAMBLE);
+        case READ_PREAMBLE:
+            byte[] preamble = new byte[MessageEncoder.PREAMBLE.length];
+            buffer.readBytes(preamble);
+            checkState(Arrays.equals(MessageEncoder.PREAMBLE, preamble), "Message has wrong preamble");
+            checkpoint(DecoderState.READ_CONTENT_LENGTH);
+        case READ_CONTENT_LENGTH:
+            contentLength = buffer.readInt();
+            checkpoint(DecoderState.READ_SERIALIZER_VERSION);
+        case READ_SERIALIZER_VERSION:
+            int serializerVersion = buffer.readInt();
+            checkState(serializerVersion == MessageEncoder.SERIALIZER_VERSION, "Unexpected serializer version");
+            checkpoint(DecoderState.READ_CONTENT);
+        case READ_CONTENT:
+            InternalMessage message = serializer.deserialize(buffer.readBytes(contentLength).nioBuffer());
+            message.setMessagingService(messagingService);
+            out.add(message);
+            checkpoint(DecoderState.READ_HEADER_VERSION);
+            break;
+         default:
+            checkState(false, "Must not be here");
+        }
     }
 }