diff --git a/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/GossipDeviceStore.java b/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/GossipDeviceStore.java
index da0a292..ab9ae3c 100644
--- a/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/GossipDeviceStore.java
+++ b/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/GossipDeviceStore.java
@@ -37,7 +37,6 @@
 import org.onlab.onos.store.cluster.messaging.ClusterCommunicationService;
 import org.onlab.onos.store.cluster.messaging.ClusterMessage;
 import org.onlab.onos.store.cluster.messaging.ClusterMessageHandler;
-import org.onlab.onos.store.cluster.messaging.MessageSubject;
 import org.onlab.onos.store.common.impl.Timestamped;
 import org.onlab.util.NewConcurrentHashMap;
 import org.slf4j.Logger;
@@ -107,6 +106,12 @@
 
     @Activate
     public void activate() {
+        clusterCommunicator.addSubscriber(
+                GossipDeviceStoreMessageSubjects.DEVICE_UPDATE, new InternalDeviceEventListener());
+        clusterCommunicator.addSubscriber(
+                GossipDeviceStoreMessageSubjects.PORT_UPDATE, new InternalPortEventListener());
+        clusterCommunicator.addSubscriber(
+                GossipDeviceStoreMessageSubjects.PORT_STATUS_UPDATE, new InternalPortStatusEventListener());
         log.info("Started");
     }
 
@@ -774,17 +779,17 @@
     }
 
     private void notifyPeers(InternalDeviceEvent event) throws IOException {
-        ClusterMessage message = new ClusterMessage(null, new MessageSubject("peer-device-updates"), event);
+        ClusterMessage message = new ClusterMessage(null, GossipDeviceStoreMessageSubjects.DEVICE_UPDATE, event);
         clusterCommunicator.broadcast(message);
     }
 
     private void notifyPeers(InternalPortEvent event) throws IOException {
-        ClusterMessage message = new ClusterMessage(null, new MessageSubject("peer-port-updates"), event);
+        ClusterMessage message = new ClusterMessage(null, GossipDeviceStoreMessageSubjects.PORT_UPDATE, event);
         clusterCommunicator.broadcast(message);
     }
 
     private void notifyPeers(InternalPortStatusEvent event) throws IOException {
-        ClusterMessage message = new ClusterMessage(null, new MessageSubject("peer-port-status-updates"), event);
+        ClusterMessage message = new ClusterMessage(null, GossipDeviceStoreMessageSubjects.PORT_STATUS_UPDATE, event);
         clusterCommunicator.broadcast(message);
     }
 
diff --git a/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/GossipDeviceStoreMessageSubjects.java b/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/GossipDeviceStoreMessageSubjects.java
new file mode 100644
index 0000000..58fed70
--- /dev/null
+++ b/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/GossipDeviceStoreMessageSubjects.java
@@ -0,0 +1,15 @@
+package org.onlab.onos.store.device.impl;
+
+import org.onlab.onos.store.cluster.messaging.MessageSubject;
+
+/**
+ * MessageSubjects used by GossipDeviceStore.
+ */
+public final class GossipDeviceStoreMessageSubjects {
+
+    private GossipDeviceStoreMessageSubjects() {}
+
+    public static final MessageSubject DEVICE_UPDATE = new MessageSubject("peer-device-update");
+    public static final MessageSubject PORT_UPDATE = new MessageSubject("peer-port-update");
+    public static final MessageSubject PORT_STATUS_UPDATE = new MessageSubject("peer-port-status-update");
+}
diff --git a/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalDeviceEvent.java b/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalDeviceEvent.java
index 2d97d25..26f1d7f 100644
--- a/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalDeviceEvent.java
+++ b/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalDeviceEvent.java
@@ -5,6 +5,10 @@
 import org.onlab.onos.net.provider.ProviderId;
 import org.onlab.onos.store.common.impl.Timestamped;
 
+/**
+ * Information published by GossipDeviceStore to notify peers of a device
+ * change event.
+ */
 public class InternalDeviceEvent {
 
     private final ProviderId providerId;
diff --git a/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalPortEvent.java b/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalPortEvent.java
index 327c185..48e3be6 100644
--- a/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalPortEvent.java
+++ b/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalPortEvent.java
@@ -7,6 +7,10 @@
 import org.onlab.onos.net.provider.ProviderId;
 import org.onlab.onos.store.common.impl.Timestamped;
 
+/**
+ * Information published by GossipDeviceStore to notify peers of a port
+ * change event.
+ */
 public class InternalPortEvent {
 
     private final ProviderId providerId;
diff --git a/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalPortStatusEvent.java b/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalPortStatusEvent.java
index 822ba7a..0bdfdbf 100644
--- a/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalPortStatusEvent.java
+++ b/core/store/dist/src/main/java/org/onlab/onos/store/device/impl/InternalPortStatusEvent.java
@@ -5,6 +5,10 @@
 import org.onlab.onos.net.provider.ProviderId;
 import org.onlab.onos.store.common.impl.Timestamped;
 
+/**
+ * Information published by GossipDeviceStore to notify peers of a port
+ * status change event.
+ */
 public class InternalPortStatusEvent {
 
     private final ProviderId providerId;