diff --git a/gms/HeartBeatState.java b/gms/HeartBeatState.java
new file mode 100644
index 0000000000..b33ef92829
--- /dev/null
+++ b/gms/HeartBeatState.java
@@ -0,0 +1,90 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.cassandra.gms;
+
+import java.io.*;
+
+import org.apache.cassandra.db.TypeSizes;
+import org.apache.cassandra.io.IVersionedSerializer;
+import org.apache.cassandra.io.util.DataOutputPlus;
+
+/**
+ * HeartBeat State associated with any given endpoint.
+ */
+class HeartBeatState
+{
+    public static final IVersionedSerializer<HeartBeatState> serializer = new HeartBeatStateSerializer();
+
+    private int generation;
+    private int version;
+
+    HeartBeatState(int gen)
+    {
+        this(gen, 0);
+    }
+
+    HeartBeatState(int gen, int ver)
+    {
+        generation = gen;
+        version = ver;
+    }
+
+    int getGeneration()
+    {
+        return generation;
+    }
+
+    void updateHeartBeat()
+    {
+        version = VersionGenerator.getNextVersion();
+    }
+
+    int getHeartBeatVersion()
+    {
+        return version;
+    }
+
+    void forceNewerGenerationUnsafe()
+    {
+        generation += 1;
+    }
+
+    public String toString()
+    {
+        return String.format("HeartBeat: generation = %d, version = %d", generation, version);
+    }
+}
+
+class HeartBeatStateSerializer implements IVersionedSerializer<HeartBeatState>
+{
+    public void serialize(HeartBeatState hbState, DataOutputPlus out, int version) throws IOException
+    {
+        out.writeInt(hbState.getGeneration());
+        out.writeInt(hbState.getHeartBeatVersion());
+    }
+
+    public HeartBeatState deserialize(DataInput in, int version) throws IOException
+    {
+        return new HeartBeatState(in.readInt(), in.readInt());
+    }
+
+    public long serializedSize(HeartBeatState state, int version)
+    {
+        return TypeSizes.NATIVE.sizeof(state.getGeneration()) + TypeSizes.NATIVE.sizeof(state.getHeartBeatVersion());
+    }
+}