diff --git a/akka-actor/src/main/scala/akka/actor/ActorRef.scala b/akka-actor/src/main/scala/akka/actor/ActorRef.scala
index 1f9e87d50b..3cfea4d22b 100644
--- a/akka-actor/src/main/scala/akka/actor/ActorRef.scala
+++ b/akka-actor/src/main/scala/akka/actor/ActorRef.scala
@@ -707,6 +707,8 @@ class LocalActorRef private[akka] (
             EventHandler.error(e, actor, messageHandle.message.toString)
             throw e
         }
+      } else {
+        // throwing away message if actor is shut down, no use throwing an exception in receiving actor's thread, isShutdown is enforced on caller side
       }
     } finally {
       guard.lock.unlock()
diff --git a/akka-actor/src/main/scala/akka/cluster/ClusterInterface.scala b/akka-actor/src/main/scala/akka/cluster/ClusterInterface.scala
index 2254fbd956..fa28f0a4f3 100644
--- a/akka-actor/src/main/scala/akka/cluster/ClusterInterface.scala
+++ b/akka-actor/src/main/scala/akka/cluster/ClusterInterface.scala
@@ -102,6 +102,9 @@ class NodeAddress(val clusterName: String, val nodeName: String) {
   override def equals(other: Any) = NodeAddress.unapply(this) == NodeAddress.unapply(other)
 }
 
+/**
+ * NodeAddress companion object and factory.
+ */
 object NodeAddress {
   def apply(clusterName: String = Config.clusterName, nodeName: String = Config.nodename): NodeAddress = new NodeAddress(clusterName, nodeName)
 
@@ -119,16 +122,7 @@ object NodeAddress {
 trait ClusterNode {
   import ChangeListener._
 
-  def nodeAddress: NodeAddress
-  def zkServerAddresses: String
-
-  def remoteClientLifeCycleListener: ActorRef
-  def remoteDaemon: ActorRef
-  def remoteService: RemoteSupport
-  def remoteServerAddress: InetSocketAddress
-
   val isConnected = new Switch(false)
-  val electionNumber = new AtomicInteger(Int.MaxValue)
 
   private[cluster] val locallyCachedMembershipNodes = new ConcurrentSkipListSet[String]()
   private[cluster] val nodeNameToAddress: ConcurrentMap[String, InetSocketAddress] = new ConcurrentHashMap[String, InetSocketAddress]
@@ -136,6 +130,14 @@ trait ClusterNode {
 
   def membershipNodes: Array[String]
 
+  def nodeAddress: NodeAddress
+
+  def zkServerAddresses: String
+
+  def remoteService: RemoteSupport
+
+  def remoteServerAddress: InetSocketAddress
+
   def isRunning: Boolean = isConnected.isOn
 
   def start(): ClusterNode
@@ -293,11 +295,6 @@ trait ClusterNode {
    */
   def remove(actorRef: ActorRef)
 
-  /**
-   * Removes actor with uuid from the cluster.
-   */
-  def remove(uuid: UUID)
-
   /**
    * Removes actor with address from the cluster.
    */
@@ -350,11 +347,6 @@ trait ClusterNode {
    */
   def release(actorAddress: String)
 
-  /**
-   * Releases (checking in) all actors with a specific UUID on all nodes in the cluster where the actor is in 'use'.
-   */
-  def releaseActorOnAllNodes(uuid: UUID)
-
   /**
    * Creates an ActorRef with a Router to a set of clustered actors.
    */
@@ -370,51 +362,16 @@ trait ClusterNode {
    */
   def migrate(from: NodeAddress, to: NodeAddress, actorAddress: String)
 
-  /**
-   * Returns the UUIDs of all actors checked out on this node.
-   */
-  def uuidsForActorsInUse: Array[UUID]
-
   /**
    * Returns the addresses of all actors checked out on this node.
    */
   def addressesForActorsInUse: Array[String]
 
-  /**
-   * Returns the UUIDs of all actors registered in this cluster.
-   */
-  def uuidsForClusteredActors: Array[UUID]
-
   /**
    * Returns the addresses of all actors registered in this cluster.
    */
   def addressesForClusteredActors: Array[String]
 
-  /**
-   * Returns the actor id for the actor with a specific UUID.
-   */
-  def actorAddressForUuid(uuid: UUID): Option[String]
-
-  /**
-   * Returns the actor ids for all the actors with a specific UUID.
-   */
-  def actorAddressForUuids(uuids: Array[UUID]): Array[String]
-
-  /**
-   * Returns the actor UUIDs for actor ID.
-   */
-  def uuidsForActorAddress(actorAddress: String): Array[UUID]
-
-  /**
-   * Returns the node names of all actors in use with UUID.
-   */
-  def nodesForActorsInUseWithUuid(uuid: UUID): Array[String]
-
-  /**
-   * Returns the UUIDs of all actors in use registered on a specific node.
-   */
-  def uuidsForActorsInUseOnNode(nodeName: String): Array[UUID]
-
   /**
    * Returns the addresses of all actors in use registered on a specific node.
    */
@@ -477,6 +434,56 @@ trait ClusterNode {
    */
   def getConfigElementKeys: Array[String]
 
+  // =============== PRIVATE METHODS ===============
+
+  private[cluster] def remoteClientLifeCycleListener: ActorRef
+  private[cluster] def remoteDaemon: ActorRef
+
+  /**
+   * Removes actor with uuid from the cluster.
+   */
+  private[cluster] def remove(uuid: UUID)
+
+  /**
+   * Releases (checking in) all actors with a specific UUID on all nodes in the cluster where the actor is in 'use'.
+   */
+  private[cluster] def releaseActorOnAllNodes(uuid: UUID)
+
+  /**
+   * Returns the UUIDs of all actors checked out on this node.
+   */
+  private[cluster] def uuidsForActorsInUse: Array[UUID]
+
+  /**
+   * Returns the UUIDs of all actors registered in this cluster.
+   */
+  private[cluster] def uuidsForClusteredActors: Array[UUID]
+
+  /**
+   * Returns the actor id for the actor with a specific UUID.
+   */
+  private[cluster] def actorAddressForUuid(uuid: UUID): Option[String]
+
+  /**
+   * Returns the actor ids for all the actors with a specific UUID.
+   */
+  private[cluster] def actorAddressForUuids(uuids: Array[UUID]): Array[String]
+
+  /**
+   * Returns the actor UUIDs for actor ID.
+   */
+  private[cluster] def uuidsForActorAddress(actorAddress: String): Array[UUID]
+
+  /**
+   * Returns the node names of all actors in use with UUID.
+   */
+  private[cluster] def nodesForActorsInUseWithUuid(uuid: UUID): Array[String]
+
+  /**
+   * Returns the UUIDs of all actors in use registered on a specific node.
+   */
+  private[cluster] def uuidsForActorsInUseOnNode(nodeName: String): Array[UUID]
+
   private[cluster] def initializeNode()
 
   private[cluster] def publish(change: ChangeNotification)
diff --git a/akka-cluster/src/main/scala/akka/cluster/Cluster.scala b/akka-cluster/src/main/scala/akka/cluster/Cluster.scala
index f85d3484ff..1ef271f52b 100644
--- a/akka-cluster/src/main/scala/akka/cluster/Cluster.scala
+++ b/akka-cluster/src/main/scala/akka/cluster/Cluster.scala
@@ -286,7 +286,7 @@ class DefaultClusterNode private[akka] (
 
   import Cluster._
 
-  lazy val remoteClientLifeCycleListener = localActorOf(new Actor {
+  private[cluster] lazy val remoteClientLifeCycleListener = localActorOf(new Actor {
     def receive = {
       case RemoteClientError(cause, client, address) ⇒ client.shutdownClientModule()
       case RemoteClientDisconnected(client, address) ⇒ client.shutdownClientModule()
@@ -294,9 +294,9 @@ class DefaultClusterNode private[akka] (
     }
   }, "akka.cluster.RemoteClientLifeCycleListener").start()
 
-  lazy val remoteDaemon = localActorOf(new RemoteClusterDaemon(this), RemoteClusterDaemon.ADDRESS).start()
+  private[cluster] lazy val remoteDaemon = localActorOf(new RemoteClusterDaemon(this), RemoteClusterDaemon.ADDRESS).start()
 
-  lazy val remoteDaemonSupervisor = Supervisor(
+  private[cluster] lazy val remoteDaemonSupervisor = Supervisor(
     SupervisorConfig(
       OneForOneStrategy(List(classOf[Exception]), Int.MaxValue, Int.MaxValue), // is infinite restart what we want?
       Supervise(
@@ -853,7 +853,7 @@ class DefaultClusterNode private[akka] (
   /**
    * Releases (checking in) all actors with a specific UUID on all nodes in the cluster where the actor is in 'use'.
    */
-  def releaseActorOnAllNodes(uuid: UUID) {
+  private[akka] def releaseActorOnAllNodes(uuid: UUID) {
     isConnected ifOn {
       EventHandler.debug(this,
         "Releasing (checking in) all actors with UUID [%s] on all nodes in cluster".format(uuid))
@@ -914,7 +914,7 @@ class DefaultClusterNode private[akka] (
   /**
    * Returns the UUIDs of all actors checked out on this node.
    */
-  def uuidsForActorsInUse: Array[UUID] = uuidsForActorsInUseOnNode(nodeAddress.nodeName)
+  private[akka] def uuidsForActorsInUse: Array[UUID] = uuidsForActorsInUseOnNode(nodeAddress.nodeName)
 
   /**
    * Returns the addresses of all actors checked out on this node.
@@ -924,7 +924,7 @@ class DefaultClusterNode private[akka] (
   /**
    * Returns the UUIDs of all actors registered in this cluster.
    */
-  def uuidsForClusteredActors: Array[UUID] = if (isConnected.isOn) {
+  private[akka] def uuidsForClusteredActors: Array[UUID] = if (isConnected.isOn) {
     zkClient.getChildren(ACTOR_REGISTRY_PATH).toList.map(new UUID(_)).toArray.asInstanceOf[Array[UUID]]
   } else Array.empty[UUID]
 
@@ -936,7 +936,7 @@ class DefaultClusterNode private[akka] (
   /**
    * Returns the actor id for the actor with a specific UUID.
    */
-  def actorAddressForUuid(uuid: UUID): Option[String] = if (isConnected.isOn) {
+  private[akka] def actorAddressForUuid(uuid: UUID): Option[String] = if (isConnected.isOn) {
     try {
       Some(zkClient.readData(actorRegistryActorAddressPathFor(uuid)).asInstanceOf[String])
     } catch {
@@ -947,13 +947,13 @@ class DefaultClusterNode private[akka] (
   /**
    * Returns the actor ids for all the actors with a specific UUID.
    */
-  def actorAddressForUuids(uuids: Array[UUID]): Array[String] =
+  private[akka] def actorAddressForUuids(uuids: Array[UUID]): Array[String] =
     uuids map (actorAddressForUuid(_)) filter (_.isDefined) map (_.get)
 
   /**
    * Returns the actor UUIDs for actor ID.
    */
-  def uuidsForActorAddress(actorAddress: String): Array[UUID] = if (isConnected.isOn) {
+  private[akka] def uuidsForActorAddress(actorAddress: String): Array[UUID] = if (isConnected.isOn) {
     try {
       zkClient.getChildren(actorAddressToUuidsPathFor(actorAddress)).toArray map {
         case c: CharSequence ⇒ new UUID(c)
@@ -966,7 +966,7 @@ class DefaultClusterNode private[akka] (
   /**
    * Returns the node names of all actors in use with UUID.
    */
-  def nodesForActorsInUseWithUuid(uuid: UUID): Array[String] = if (isConnected.isOn) {
+  private[akka] def nodesForActorsInUseWithUuid(uuid: UUID): Array[String] = if (isConnected.isOn) {
     try {
       zkClient.getChildren(actorLocationsPathFor(uuid)).toArray.asInstanceOf[Array[String]]
     } catch {
@@ -992,7 +992,7 @@ class DefaultClusterNode private[akka] (
   /**
    * Returns the UUIDs of all actors in use registered on a specific node.
    */
-  def uuidsForActorsInUseOnNode(nodeName: String): Array[UUID] = if (isConnected.isOn) {
+  private[akka] def uuidsForActorsInUseOnNode(nodeName: String): Array[UUID] = if (isConnected.isOn) {
     try {
       zkClient.getChildren(actorsAtNodePathFor(nodeName)).toArray map {
         case c: CharSequence ⇒ new UUID(c)