Merge branch 'master' of ssh://gerrit.onlab.us:29418/onos-next

Conflicts:
	core/net/src/main/java/org/onlab/onos/net/proxyarp/impl/package-info.java

Change-Id: I7bf076fae02c619ff0d57ffcbff4a4189716c474

@@ -28,10 +28,6 @@
             <version>${project.version}</version>
             <version>${project.version}</version>
         </dependency>
         </dependency>
         <dependency>
         <dependency>
-            <groupId>org.livetribe.slp</groupId>
-            <artifactId>livetribe-slp</artifactId>
-        </dependency>
-        <dependency>
             <groupId>org.apache.karaf.shell</groupId>
             <groupId>org.apache.karaf.shell</groupId>
             <artifactId>org.apache.karaf.shell.console</artifactId>
             <artifactId>org.apache.karaf.shell.console</artifactId>
         </dependency>
         </dependency>

@@ -233,7 +233,7 @@ public class IOLoopTestClient {
         }
         }
 
 
         @Override
         @Override
-        protected void connect(SelectionKey key) {
+        protected void connect(SelectionKey key) throws IOException {
             super.connect(key);
             super.connect(key);
             TestMessageStream b = (TestMessageStream) key.attachment();
             TestMessageStream b = (TestMessageStream) key.attachment();
             Worker w = ((CustomIOLoop) b.loop()).worker;
             Worker w = ((CustomIOLoop) b.loop()).worker;

+livetribe.slp.da.expired.services.purge.period=60
+livetribe.slp.sa.client.connect.address=127.0.0.1
+livetribe.slp.sa.client.factory=org.livetribe.slp.sa.StandardServiceAgentClient$Factory
+livetribe.slp.sa.factory=org.livetribe.slp.sa.StandardServiceAgent$Factory
+livetribe.slp.sa.service.renewal.enabled=true
+livetribe.slp.sa.unicast.prefer.tcp=false
+livetribe.slp.tcp.connector.factory=org.livetribe.slp.spi.net.SocketTCPConnector$Factory
+livetribe.slp.tcp.connector.server.factory=org.livetribe.slp.spi.net.SocketTCPConnectorServer$Factory
+livetribe.slp.tcp.message.max.length=4096
+livetribe.slp.tcp.read.timeout=300000
+livetribe.slp.ua.client.factory=org.livetribe.slp.ua.StandardUserAgentClient$Factory
+livetribe.slp.ua.factory=org.livetribe.slp.ua.StandardUserAgent$Factory
+livetribe.slp.ua.unicast.prefer.tcp=false
+livetribe.slp.udp.connector.factory=org.livetribe.slp.spi.net.SocketUDPConnector$Factory
+livetribe.slp.udp.connector.server.factory=org.livetribe.slp.spi.net.SocketUDPConnectorServer$Factory
+net.slp.DAAddresses=
+net.slp.DAAttributes=
+net.slp.DAHeartBeat=10800
+net.slp.MTU=1400
+net.slp.SAAttributes=
+net.slp.broadcastAddress=255.255.255.255
+net.slp.datagramTimeouts=150,250,400
+net.slp.interfaces=0.0.0.0
+net.slp.isBroadcastOnly=false
+net.slp.locale=en
+net.slp.multicastAddress=239.255.255.253
+net.slp.multicastMaximumWait=15000
+net.slp.multicastTTL=255
+net.slp.multicastTimeouts=150,250,400,600,1000
+net.slp.notificationPort=1847
+net.slp.port=427
+net.slp.useScopes=default
+
+org.onlab.cluster.name = TV-ONOS

+package org.onlab.onos.cli;
+
+import org.apache.karaf.shell.commands.Argument;
+import org.apache.karaf.shell.commands.Command;
+import org.onlab.onos.cluster.ClusterAdminService;
+import org.onlab.onos.cluster.NodeId;
+import org.onlab.packet.IpPrefix;
+
+/**
+ * Adds a new controller cluster node.
+ */
+@Command(scope = "onos", name = "add-node",
+         description = "Adds a new controller cluster node")
+public class NodeAddCommand extends AbstractShellCommand {
+
+    @Argument(index = 0, name = "nodeId", description = "Node ID",
+              required = true, multiValued = false)
+    String nodeId = null;
+
+    @Argument(index = 1, name = "ip", description = "Node IP address",
+              required = true, multiValued = false)
+    String ip = null;
+
+    @Argument(index = 2, name = "tcpPort", description = "Node TCP listen port",
+              required = false, multiValued = false)
+    int tcpPort = 9876;
+
+    @Override
+    protected void execute() {
+        ClusterAdminService service = get(ClusterAdminService.class);
+        service.addNode(new NodeId(nodeId), IpPrefix.valueOf(ip), tcpPort);
+    }
+
+}

+package org.onlab.onos.cli;
+
+import org.apache.karaf.shell.commands.Argument;
+import org.apache.karaf.shell.commands.Command;
+import org.onlab.onos.cluster.ClusterAdminService;
+import org.onlab.onos.cluster.NodeId;
+
+/**
+ * Removes a controller cluster node.
+ */
+@Command(scope = "onos", name = "remove-node",
+         description = "Removes a new controller cluster node")
+public class NodeRemoveCommand extends AbstractShellCommand {
+
+    @Argument(index = 0, name = "nodeId", description = "Node ID",
+              required = true, multiValued = false)
+    String nodeId = null;
+
+    @Override
+    protected void execute() {
+        ClusterAdminService service = get(ClusterAdminService.class);
+        service.removeNode(new NodeId(nodeId));
+    }
+
+}

@@ -17,7 +17,7 @@ import static com.google.common.collect.Lists.newArrayList;
 public class NodesListCommand extends AbstractShellCommand {
 public class NodesListCommand extends AbstractShellCommand {
 
 
     private static final String FMT =
     private static final String FMT =
-            "id=%s, ip=%s, state=%s %s";
+            "id=%s, address=%s:%s, state=%s %s";
 
 
     @Override
     @Override
     protected void execute() {
     protected void execute() {
@@ -26,7 +26,7 @@ public class NodesListCommand extends AbstractShellCommand {
         Collections.sort(nodes, Comparators.NODE_COMPARATOR);
         Collections.sort(nodes, Comparators.NODE_COMPARATOR);
         ControllerNode self = service.getLocalNode();
         ControllerNode self = service.getLocalNode();
         for (ControllerNode node : nodes) {
         for (ControllerNode node : nodes) {
-            print(FMT, node.id(), node.ip(),
+            print(FMT, node.id(), node.ip(), node.tcpPort(),
                   service.getState(node.id()),
                   service.getState(node.id()),
                   node.equals(self) ? "*" : "");
                   node.equals(self) ? "*" : "");
         }
         }

@@ -5,6 +5,12 @@
             <action class="org.onlab.onos.cli.NodesListCommand"/>
             <action class="org.onlab.onos.cli.NodesListCommand"/>
         </command>
         </command>
         <command>
         <command>
+            <action class="org.onlab.onos.cli.NodeAddCommand"/>
+        </command>
+        <command>
+            <action class="org.onlab.onos.cli.NodeRemoveCommand"/>
+        </command>
+        <command>
             <action class="org.onlab.onos.cli.MastersListCommand"/>
             <action class="org.onlab.onos.cli.MastersListCommand"/>
             <completers>
             <completers>
                 <ref component-id="clusterIdCompleter"/>
                 <ref component-id="clusterIdCompleter"/>

 package org.onlab.onos.cluster;
 package org.onlab.onos.cluster;
 
 
+import org.onlab.packet.IpPrefix;
+
 /**
 /**
  * Service for administering the cluster node membership.
  * Service for administering the cluster node membership.
  */
  */
 public interface ClusterAdminService {
 public interface ClusterAdminService {
 
 
     /**
     /**
+     * Adds a new controller node to the cluster.
+     *
+     * @param nodeId  controller node identifier
+     * @param ip      node IP listen address
+     * @param tcpPort tcp listen port
+     * @return newly added node
+     */
+    ControllerNode addNode(NodeId nodeId, IpPrefix ip, int tcpPort);
+
+    /**
      * Removes the specified node from the cluster node list.
      * Removes the specified node from the cluster node list.
      *
      *
      * @param nodeId controller node identifier
      * @param nodeId controller node identifier

 package org.onlab.onos.cluster;
 package org.onlab.onos.cluster;
 
 
 import org.onlab.onos.store.Store;
 import org.onlab.onos.store.Store;
+import org.onlab.packet.IpPrefix;
 
 
 import java.util.Set;
 import java.util.Set;
 
 
@@ -40,6 +41,16 @@ public interface ClusterStore extends Store<ClusterEvent, ClusterStoreDelegate>
     ControllerNode.State getState(NodeId nodeId);
     ControllerNode.State getState(NodeId nodeId);
 
 
     /**
     /**
+     * Adds a new controller node to the cluster.
+     *
+     * @param nodeId  controller node identifier
+     * @param ip      node IP listen address
+     * @param tcpPort tcp listen port
+     * @return newly added node
+     */
+    ControllerNode addNode(NodeId nodeId, IpPrefix ip, int tcpPort);
+
+    /**
      * Removes the specified node from the inventory of cluster nodes.
      * Removes the specified node from the inventory of cluster nodes.
      *
      *
      * @param nodeId controller instance identifier
      * @param nodeId controller instance identifier

@@ -35,4 +35,12 @@ public interface ControllerNode {
      */
      */
     IpPrefix ip();
     IpPrefix ip();
 
 
+
+    /**
+     * Returns the TCP port on which the node listens for connections.
+     *
+     * @return TCP port
+     */
+    int tcpPort();
+
 }
 }

@@ -11,13 +11,17 @@ import static com.google.common.base.MoreObjects.toStringHelper;
  */
  */
 public class DefaultControllerNode implements ControllerNode {
 public class DefaultControllerNode implements ControllerNode {
 
 
+    private static final int DEFAULT_PORT = 9876;
+
     private final NodeId id;
     private final NodeId id;
     private final IpPrefix ip;
     private final IpPrefix ip;
+    private final int tcpPort;
 
 
     // For serialization
     // For serialization
     private DefaultControllerNode() {
     private DefaultControllerNode() {
         this.id = null;
         this.id = null;
         this.ip = null;
         this.ip = null;
+        this.tcpPort = 0;
     }
     }
 
 
     /**
     /**
@@ -27,8 +31,19 @@ public class DefaultControllerNode implements ControllerNode {
      * @param ip instance IP address
      * @param ip instance IP address
      */
      */
     public DefaultControllerNode(NodeId id, IpPrefix ip) {
     public DefaultControllerNode(NodeId id, IpPrefix ip) {
+        this(id, ip, DEFAULT_PORT);
+    }
+
+    /**
+     * Creates a new instance with the specified id and IP address and TCP port.
+     *
+     * @param id instance identifier
+     * @param ip instance IP address
+     */
+    public DefaultControllerNode(NodeId id, IpPrefix ip, int tcpPort) {
         this.id = id;
         this.id = id;
         this.ip = ip;
         this.ip = ip;
+        this.tcpPort = tcpPort;
     }
     }
 
 
     @Override
     @Override
@@ -42,6 +57,11 @@ public class DefaultControllerNode implements ControllerNode {
     }
     }
 
 
     @Override
     @Override
+    public int tcpPort() {
+        return tcpPort;
+    }
+
+    @Override
     public int hashCode() {
     public int hashCode() {
         return Objects.hash(id);
         return Objects.hash(id);
     }
     }
@@ -60,7 +80,8 @@ public class DefaultControllerNode implements ControllerNode {
 
 
     @Override
     @Override
     public String toString() {
     public String toString() {
-        return toStringHelper(this).add("id", id).add("ip", ip).toString();
+        return toStringHelper(this).add("id", id)
+                .add("ip", ip).add("tcpPort", tcpPort).toString();
     }
     }
 
 
 }
 }

 /**
 /**
  * Base abstractions related to the proxy arp service.
  * Base abstractions related to the proxy arp service.
  */
  */
-package org.onlab.onos.net.proxyarp;
\ No newline at end of file
+package org.onlab.onos.net.proxyarp;

@@ -16,10 +16,12 @@ import org.onlab.onos.cluster.ControllerNode;
 import org.onlab.onos.cluster.NodeId;
 import org.onlab.onos.cluster.NodeId;
 import org.onlab.onos.event.AbstractListenerRegistry;
 import org.onlab.onos.event.AbstractListenerRegistry;
 import org.onlab.onos.event.EventDeliveryService;
 import org.onlab.onos.event.EventDeliveryService;
+import org.onlab.packet.IpPrefix;
 import org.slf4j.Logger;
 import org.slf4j.Logger;
 
 
 import java.util.Set;
 import java.util.Set;
 
 
+import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkNotNull;
 import static org.slf4j.LoggerFactory.getLogger;
 import static org.slf4j.LoggerFactory.getLogger;
 
 
@@ -81,6 +83,14 @@ public class ClusterManager implements ClusterService, ClusterAdminService {
     }
     }
 
 
     @Override
     @Override
+    public ControllerNode addNode(NodeId nodeId, IpPrefix ip, int tcpPort) {
+        checkNotNull(nodeId, INSTANCE_ID_NULL);
+        checkNotNull(ip, "IP address cannot be null");
+        checkArgument(tcpPort > 5000, "TCP port must be > 5000");
+        return store.addNode(nodeId, ip, tcpPort);
+    }
+
+    @Override
     public void removeNode(NodeId nodeId) {
     public void removeNode(NodeId nodeId) {
         checkNotNull(nodeId, INSTANCE_ID_NULL);
         checkNotNull(nodeId, INSTANCE_ID_NULL);
         store.removeNode(nodeId);
         store.removeNode(nodeId);

 /**
 /**
  * Core subsystem for responding to arp requests.
  * Core subsystem for responding to arp requests.
  */
  */
-package org.onlab.onos.net.proxyarp.impl;
\ No newline at end of file
+package org.onlab.onos.net.proxyarp.impl;

@@ -33,8 +33,11 @@ import org.onlab.onos.net.device.PortDescription;
 import org.onlab.onos.net.provider.AbstractProvider;
 import org.onlab.onos.net.provider.AbstractProvider;
 import org.onlab.onos.net.provider.ProviderId;
 import org.onlab.onos.net.provider.ProviderId;
 import org.onlab.onos.store.common.StoreManager;
 import org.onlab.onos.store.common.StoreManager;
+import org.onlab.onos.store.common.StoreService;
 import org.onlab.onos.store.common.TestStoreManager;
 import org.onlab.onos.store.common.TestStoreManager;
 import org.onlab.onos.store.device.impl.DistributedDeviceStore;
 import org.onlab.onos.store.device.impl.DistributedDeviceStore;
+import org.onlab.onos.store.serializers.KryoSerializationManager;
+import org.onlab.onos.store.serializers.KryoSerializationService;
 import org.onlab.packet.IpPrefix;
 import org.onlab.packet.IpPrefix;
 
 
 import java.util.ArrayList;
 import java.util.ArrayList;
@@ -92,6 +95,7 @@ public class DistributedDeviceManagerTest {
     private DistributedDeviceStore dstore;
     private DistributedDeviceStore dstore;
     private TestMastershipManager masterManager;
     private TestMastershipManager masterManager;
     private EventDeliveryService eventService;
     private EventDeliveryService eventService;
+    private KryoSerializationManager serializationMgr;
 
 
     @Before
     @Before
     public void setUp() {
     public void setUp() {
@@ -107,7 +111,10 @@ public class DistributedDeviceManagerTest {
         storeManager = new TestStoreManager(Hazelcast.newHazelcastInstance(config));
         storeManager = new TestStoreManager(Hazelcast.newHazelcastInstance(config));
         storeManager.activate();
         storeManager.activate();
 
 
-        dstore = new TestDistributedDeviceStore();
+        serializationMgr = new KryoSerializationManager();
+        serializationMgr.activate();
+
+        dstore = new TestDistributedDeviceStore(storeManager, serializationMgr);
         dstore.activate();
         dstore.activate();
 
 
         mgr.store = dstore;
         mgr.store = dstore;
@@ -133,6 +140,7 @@ public class DistributedDeviceManagerTest {
         mgr.deactivate();
         mgr.deactivate();
 
 
         dstore.deactivate();
         dstore.deactivate();
+        serializationMgr.deactivate();
         storeManager.deactivate();
         storeManager.deactivate();
     }
     }
 
 
@@ -163,7 +171,7 @@ public class DistributedDeviceManagerTest {
     public void deviceDisconnected() {
     public void deviceDisconnected() {
         connectDevice(DID1, SW1);
         connectDevice(DID1, SW1);
         connectDevice(DID2, SW1);
         connectDevice(DID2, SW1);
-        validateEvents(DEVICE_ADDED, DEVICE_ADDED, DEVICE_ADDED, DEVICE_ADDED);
+        validateEvents(DEVICE_ADDED, DEVICE_ADDED);
         assertTrue("device should be available", service.isAvailable(DID1));
         assertTrue("device should be available", service.isAvailable(DID1));
 
 
         // Disconnect
         // Disconnect
@@ -182,10 +190,10 @@ public class DistributedDeviceManagerTest {
     @Test
     @Test
     public void deviceUpdated() {
     public void deviceUpdated() {
         connectDevice(DID1, SW1);
         connectDevice(DID1, SW1);
-        validateEvents(DEVICE_ADDED, DEVICE_ADDED);
+        validateEvents(DEVICE_ADDED);
 
 
         connectDevice(DID1, SW2);
         connectDevice(DID1, SW2);
-        validateEvents(DEVICE_UPDATED, DEVICE_UPDATED);
+        validateEvents(DEVICE_UPDATED);
     }
     }
 
 
     @Test
     @Test
@@ -202,7 +210,7 @@ public class DistributedDeviceManagerTest {
         pds.add(new DefaultPortDescription(P2, true));
         pds.add(new DefaultPortDescription(P2, true));
         pds.add(new DefaultPortDescription(P3, true));
         pds.add(new DefaultPortDescription(P3, true));
         providerService.updatePorts(DID1, pds);
         providerService.updatePorts(DID1, pds);
-        validateEvents(DEVICE_ADDED, DEVICE_ADDED, PORT_ADDED, PORT_ADDED, PORT_ADDED);
+        validateEvents(DEVICE_ADDED, PORT_ADDED, PORT_ADDED, PORT_ADDED);
         pds.clear();
         pds.clear();
 
 
         pds.add(new DefaultPortDescription(P1, false));
         pds.add(new DefaultPortDescription(P1, false));
@@ -218,7 +226,7 @@ public class DistributedDeviceManagerTest {
         pds.add(new DefaultPortDescription(P1, true));
         pds.add(new DefaultPortDescription(P1, true));
         pds.add(new DefaultPortDescription(P2, true));
         pds.add(new DefaultPortDescription(P2, true));
         providerService.updatePorts(DID1, pds);
         providerService.updatePorts(DID1, pds);
-        validateEvents(DEVICE_ADDED, DEVICE_ADDED, PORT_ADDED, PORT_ADDED);
+        validateEvents(DEVICE_ADDED, PORT_ADDED, PORT_ADDED);
 
 
         providerService.portStatusChanged(DID1, new DefaultPortDescription(P1, false));
         providerService.portStatusChanged(DID1, new DefaultPortDescription(P1, false));
         validateEvents(PORT_UPDATED);
         validateEvents(PORT_UPDATED);
@@ -233,7 +241,7 @@ public class DistributedDeviceManagerTest {
         pds.add(new DefaultPortDescription(P1, true));
         pds.add(new DefaultPortDescription(P1, true));
         pds.add(new DefaultPortDescription(P2, true));
         pds.add(new DefaultPortDescription(P2, true));
         providerService.updatePorts(DID1, pds);
         providerService.updatePorts(DID1, pds);
-        validateEvents(DEVICE_ADDED, DEVICE_ADDED, PORT_ADDED, PORT_ADDED);
+        validateEvents(DEVICE_ADDED, PORT_ADDED, PORT_ADDED);
         assertEquals("wrong port count", 2, service.getPorts(DID1).size());
         assertEquals("wrong port count", 2, service.getPorts(DID1).size());
 
 
         Port port = service.getPort(DID1, P1);
         Port port = service.getPort(DID1, P1);
@@ -247,7 +255,7 @@ public class DistributedDeviceManagerTest {
         connectDevice(DID2, SW2);
         connectDevice(DID2, SW2);
         assertEquals("incorrect device count", 2, service.getDeviceCount());
         assertEquals("incorrect device count", 2, service.getDeviceCount());
         admin.removeDevice(DID1);
         admin.removeDevice(DID1);
-        validateEvents(DEVICE_ADDED, DEVICE_ADDED, DEVICE_ADDED, DEVICE_ADDED, DEVICE_REMOVED, DEVICE_REMOVED);
+        validateEvents(DEVICE_ADDED, DEVICE_ADDED, DEVICE_REMOVED);
         assertNull("device should not be found", service.getDevice(DID1));
         assertNull("device should not be found", service.getDevice(DID1));
         assertNotNull("device should be found", service.getDevice(DID2));
         assertNotNull("device should be found", service.getDevice(DID2));
         assertEquals("incorrect device count", 1, service.getDeviceCount());
         assertEquals("incorrect device count", 1, service.getDeviceCount());
@@ -298,8 +306,10 @@ public class DistributedDeviceManagerTest {
 
 
     private class TestDistributedDeviceStore extends DistributedDeviceStore {
     private class TestDistributedDeviceStore extends DistributedDeviceStore {
 
 
-        public TestDistributedDeviceStore() {
-            this.storeService = storeManager;
+        public TestDistributedDeviceStore(StoreService storeService,
+                                    KryoSerializationService kryoSerializationService) {
+            this.storeService = storeService;
+            this.kryoSerializationService = kryoSerializationService;
         }
         }
     }
     }
 
 

@@ -26,6 +26,23 @@
             <artifactId>onos-core-serializers</artifactId>
             <artifactId>onos-core-serializers</artifactId>
             <version>${project.version}</version>
             <version>${project.version}</version>
         </dependency>
         </dependency>
+
+
+        <dependency>
+            <groupId>org.onlab.onos</groupId>
+            <artifactId>onlab-nio</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-annotations</artifactId>
+        </dependency>
+
         <dependency>
         <dependency>
             <groupId>org.apache.felix</groupId>
             <groupId>org.apache.felix</groupId>
             <artifactId>org.apache.felix.scr.annotations</artifactId>
             <artifactId>org.apache.felix.scr.annotations</artifactId>

+package org.onlab.onos.store.cluster.impl;
+
+import com.fasterxml.jackson.core.JsonEncoding;
+import com.fasterxml.jackson.core.JsonFactory;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onlab.onos.cluster.DefaultControllerNode;
+import org.onlab.onos.cluster.NodeId;
+import org.onlab.packet.IpPrefix;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Set;
+
+/**
+ * Allows for reading and writing cluster definition as a JSON file.
+ */
+public class ClusterDefinitionStore {
+
+    private final File file;
+
+    /**
+     * Creates a reader/writer of the cluster definition file.
+     *
+     * @param filePath location of the definition file
+     */
+    public ClusterDefinitionStore(String filePath) {
+        file = new File(filePath);
+    }
+
+    /**
+     * Returns set of the controller nodes, including self.
+     *
+     * @return set of controller nodes
+     */
+    public Set<DefaultControllerNode> read() throws IOException {
+        Set<DefaultControllerNode> nodes = new HashSet<>();
+        ObjectMapper mapper = new ObjectMapper();
+        ObjectNode clusterNodeDef = (ObjectNode) mapper.readTree(file);
+        Iterator<JsonNode> it = ((ArrayNode) clusterNodeDef.get("nodes")).elements();
+        while (it.hasNext()) {
+            ObjectNode nodeDef = (ObjectNode) it.next();
+            nodes.add(new DefaultControllerNode(new NodeId(nodeDef.get("id").asText()),
+                                                IpPrefix.valueOf(nodeDef.get("ip").asText()),
+                                                nodeDef.get("tcpPort").asInt(9876)));
+        }
+        return nodes;
+    }
+
+    /**
+     * Writes the given set of the controller nodes.
+     *
+     * @param nodes set of controller nodes
+     */
+    public void write(Set<DefaultControllerNode> nodes) throws IOException {
+        ObjectMapper mapper = new ObjectMapper();
+        ObjectNode clusterNodeDef = mapper.createObjectNode();
+        ArrayNode nodeDefs = mapper.createArrayNode();
+        clusterNodeDef.set("nodes", nodeDefs);
+        for (DefaultControllerNode node : nodes) {
+            ObjectNode nodeDef = mapper.createObjectNode();
+            nodeDef.put("id", node.id().toString())
+                    .put("ip", node.ip().toString())
+                    .put("tcpPort", node.tcpPort());
+            nodeDefs.add(nodeDef);
+        }
+        mapper.writeTree(new JsonFactory().createGenerator(file, JsonEncoding.UTF8),
+                         clusterNodeDef);
+    }
+
+}

+package org.onlab.onos.store.cluster.impl;
+
+import com.google.common.collect.ImmutableSet;
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Service;
+import org.onlab.nio.AcceptorLoop;
+import org.onlab.nio.IOLoop;
+import org.onlab.nio.MessageStream;
+import org.onlab.onos.cluster.ClusterEvent;
+import org.onlab.onos.cluster.ClusterStore;
+import org.onlab.onos.cluster.ClusterStoreDelegate;
+import org.onlab.onos.cluster.ControllerNode;
+import org.onlab.onos.cluster.DefaultControllerNode;
+import org.onlab.onos.cluster.NodeId;
+import org.onlab.onos.store.AbstractStore;
+import org.onlab.packet.IpPrefix;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.Socket;
+import java.net.SocketAddress;
+import java.nio.channels.ByteChannel;
+import java.nio.channels.SelectionKey;
+import java.nio.channels.ServerSocketChannel;
+import java.nio.channels.SocketChannel;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+import java.util.Timer;
+import java.util.TimerTask;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+import static java.net.InetAddress.getByAddress;
+import static org.onlab.onos.cluster.ControllerNode.State;
+import static org.onlab.packet.IpPrefix.valueOf;
+import static org.onlab.util.Tools.namedThreads;
+
+/**
+ * Distributed implementation of the cluster nodes store.
+ */
+@Component(immediate = true)
+@Service
+public class DistributedClusterStore
+        extends AbstractStore<ClusterEvent, ClusterStoreDelegate>
+        implements ClusterStore {
+
+    private static final int HELLO_MSG = 1;
+    private static final int ECHO_MSG = 2;
+
+    private final Logger log = LoggerFactory.getLogger(getClass());
+
+    private static final long CONNECTION_CUSTODIAN_DELAY = 1000L;
+    private static final long CONNECTION_CUSTODIAN_FREQUENCY = 5000;
+
+    private static final long START_TIMEOUT = 1000;
+    private static final long SELECT_TIMEOUT = 50;
+    private static final int WORKERS = 3;
+    private static final int COMM_BUFFER_SIZE = 32 * 1024;
+    private static final int COMM_IDLE_TIME = 500;
+
+    private static final boolean SO_NO_DELAY = false;
+    private static final int SO_SEND_BUFFER_SIZE = COMM_BUFFER_SIZE;
+    private static final int SO_RCV_BUFFER_SIZE = COMM_BUFFER_SIZE;
+
+    private DefaultControllerNode self;
+    private final Map<NodeId, DefaultControllerNode> nodes = new ConcurrentHashMap<>();
+    private final Map<NodeId, State> states = new ConcurrentHashMap<>();
+
+    // Means to track message streams to other nodes.
+    private final Map<NodeId, TLVMessageStream> streams = new ConcurrentHashMap<>();
+    private final Map<SocketChannel, DefaultControllerNode> nodesByChannel = new ConcurrentHashMap<>();
+
+    // Executor pools for listening and managing connections to other nodes.
+    private final ExecutorService listenExecutor =
+            Executors.newSingleThreadExecutor(namedThreads("onos-comm-listen"));
+    private final ExecutorService commExecutors =
+            Executors.newFixedThreadPool(WORKERS, namedThreads("onos-comm-cluster"));
+    private final ExecutorService heartbeatExecutor =
+            Executors.newSingleThreadExecutor(namedThreads("onos-comm-heartbeat"));
+
+    private final Timer timer = new Timer("onos-comm-initiator");
+    private final TimerTask connectionCustodian = new ConnectionCustodian();
+
+    private ListenLoop listenLoop;
+    private List<CommLoop> commLoops = new ArrayList<>(WORKERS);
+
+    @Activate
+    public void activate() {
+        loadClusterDefinition();
+        startCommunications();
+        startListening();
+        startInitiating();
+        log.info("Started");
+    }
+
+    @Deactivate
+    public void deactivate() {
+        listenLoop.shutdown();
+        for (CommLoop loop : commLoops) {
+            loop.shutdown();
+        }
+        log.info("Stopped");
+    }
+
+    // Loads the cluster definition file
+    private void loadClusterDefinition() {
+//        ClusterDefinitionStore cds = new ClusterDefinitionStore("../config/cluster.json");
+//        try {
+//            Set<DefaultControllerNode> storedNodes = cds.read();
+//            for (DefaultControllerNode node : storedNodes) {
+//                nodes.put(node.id(), node);
+//            }
+//        } catch (IOException e) {
+//            log.error("Unable to read cluster definitions", e);
+//        }
+
+        // Establishes the controller's own identity.
+        IpPrefix ip = valueOf(System.getProperty("onos.ip", "127.0.1.1"));
+        self = nodes.get(new NodeId(ip.toString()));
+
+        // As a fall-back, let's make sure we at least know who we are.
+        if (self == null) {
+            self = new DefaultControllerNode(new NodeId(ip.toString()), ip);
+            nodes.put(self.id(), self);
+            states.put(self.id(), State.ACTIVE);
+        }
+    }
+
+    // Kicks off the IO loops.
+    private void startCommunications() {
+        for (int i = 0; i < WORKERS; i++) {
+            try {
+                CommLoop loop = new CommLoop();
+                commLoops.add(loop);
+                commExecutors.execute(loop);
+            } catch (IOException e) {
+                log.warn("Unable to start comm IO loop", e);
+            }
+        }
+
+        // Wait for the IO loops to start
+        for (CommLoop loop : commLoops) {
+            if (!loop.awaitStart(START_TIMEOUT)) {
+                log.warn("Comm loop did not start on-time; moving on...");
+            }
+        }
+    }
+
+    // Starts listening for connections from peer cluster members.
+    private void startListening() {
+        try {
+            listenLoop = new ListenLoop(self.ip(), self.tcpPort());
+            listenExecutor.execute(listenLoop);
+            if (!listenLoop.awaitStart(START_TIMEOUT)) {
+                log.warn("Listen loop did not start on-time; moving on...");
+            }
+        } catch (IOException e) {
+            log.error("Unable to listen for cluster connections", e);
+        }
+    }
+
+    /**
+     * Initiates open connection request and registers the pending socket
+     * channel with the given IO loop.
+     *
+     * @param loop loop with which the channel should be registered
+     * @throws java.io.IOException if the socket could not be open or connected
+     */
+    private void openConnection(DefaultControllerNode node, CommLoop loop) throws IOException {
+        SocketAddress sa = new InetSocketAddress(getByAddress(node.ip().toOctets()), node.tcpPort());
+        SocketChannel ch = SocketChannel.open();
+        nodesByChannel.put(ch, node);
+        ch.configureBlocking(false);
+        ch.connect(sa);
+        loop.connectStream(ch);
+    }
+
+
+    // Attempts to connect to any nodes that do not have an associated connection.
+    private void startInitiating() {
+        timer.schedule(connectionCustodian, CONNECTION_CUSTODIAN_DELAY, CONNECTION_CUSTODIAN_FREQUENCY);
+    }
+
+    @Override
+    public ControllerNode getLocalNode() {
+        return self;
+    }
+
+    @Override
+    public Set<ControllerNode> getNodes() {
+        ImmutableSet.Builder<ControllerNode> builder = ImmutableSet.builder();
+        return builder.addAll(nodes.values()).build();
+    }
+
+    @Override
+    public ControllerNode getNode(NodeId nodeId) {
+        return nodes.get(nodeId);
+    }
+
+    @Override
+    public State getState(NodeId nodeId) {
+        State state = states.get(nodeId);
+        return state == null ? State.INACTIVE : state;
+    }
+
+    @Override
+    public ControllerNode addNode(NodeId nodeId, IpPrefix ip, int tcpPort) {
+        DefaultControllerNode node = new DefaultControllerNode(nodeId, ip, tcpPort);
+        nodes.put(nodeId, node);
+        return node;
+    }
+
+    @Override
+    public void removeNode(NodeId nodeId) {
+        nodes.remove(nodeId);
+        TLVMessageStream stream = streams.remove(nodeId);
+        if (stream != null) {
+            stream.close();
+        }
+    }
+
+    // Listens and accepts inbound connections from other cluster nodes.
+    private class ListenLoop extends AcceptorLoop {
+        ListenLoop(IpPrefix ip, int tcpPort) throws IOException {
+            super(SELECT_TIMEOUT, new InetSocketAddress(getByAddress(ip.toOctets()), tcpPort));
+        }
+
+        @Override
+        protected void acceptConnection(ServerSocketChannel channel) throws IOException {
+            SocketChannel sc = channel.accept();
+            sc.configureBlocking(false);
+
+            Socket so = sc.socket();
+            so.setTcpNoDelay(SO_NO_DELAY);
+            so.setReceiveBufferSize(SO_RCV_BUFFER_SIZE);
+            so.setSendBufferSize(SO_SEND_BUFFER_SIZE);
+
+            findLeastUtilizedLoop().acceptStream(sc);
+        }
+    }
+
+    private class CommLoop extends IOLoop<TLVMessage, TLVMessageStream> {
+        CommLoop() throws IOException {
+            super(SELECT_TIMEOUT);
+        }
+
+        @Override
+        protected TLVMessageStream createStream(ByteChannel byteChannel) {
+            return new TLVMessageStream(this, byteChannel, COMM_BUFFER_SIZE, COMM_IDLE_TIME);
+        }
+
+        @Override
+        protected void processMessages(List<TLVMessage> messages, MessageStream<TLVMessage> stream) {
+            TLVMessageStream tlvStream = (TLVMessageStream) stream;
+            for (TLVMessage message : messages) {
+                // TODO: add type-based dispatching here... this is just a hack to get going
+                if (message.type() == HELLO_MSG) {
+                    processHello(message, tlvStream);
+                } else if (message.type() == ECHO_MSG) {
+                    processEcho(message, tlvStream);
+                } else {
+                    log.info("Deal with other messages");
+                }
+            }
+        }
+
+        @Override
+        public TLVMessageStream acceptStream(SocketChannel channel) {
+            TLVMessageStream stream = super.acceptStream(channel);
+            try {
+                InetSocketAddress sa = (InetSocketAddress) channel.getRemoteAddress();
+                log.info("Accepted connection from node {}", valueOf(sa.getAddress().getAddress()));
+                stream.write(createHello(self));
+
+            } catch (IOException e) {
+                log.warn("Unable to accept connection from an unknown end-point", e);
+            }
+            return stream;
+        }
+
+        @Override
+        public TLVMessageStream connectStream(SocketChannel channel) {
+            TLVMessageStream stream = super.connectStream(channel);
+            DefaultControllerNode node = nodesByChannel.get(channel);
+            if (node != null) {
+                log.debug("Opened connection to node {}", node.id());
+                nodesByChannel.remove(channel);
+            }
+            return stream;
+        }
+
+        @Override
+        protected void connect(SelectionKey key) throws IOException {
+            try {
+                super.connect(key);
+                TLVMessageStream stream = (TLVMessageStream) key.attachment();
+                send(stream, createHello(self));
+            } catch (IOException e) {
+                if (!Objects.equals(e.getMessage(), "Connection refused")) {
+                    throw e;
+                }
+            }
+        }
+
+        @Override
+        protected void removeStream(MessageStream<TLVMessage> stream) {
+            DefaultControllerNode node = ((TLVMessageStream) stream).node();
+            if (node != null) {
+                log.info("Closed connection to node {}", node.id());
+                states.put(node.id(), State.INACTIVE);
+                streams.remove(node.id());
+            }
+            super.removeStream(stream);
+        }
+    }
+
+    // Processes a HELLO message from a peer controller node.
+    private void processHello(TLVMessage message, TLVMessageStream stream) {
+        // FIXME: pure hack for now
+        String data = new String(message.data());
+        String[] fields = data.split(":");
+        DefaultControllerNode node = new DefaultControllerNode(new NodeId(fields[0]),
+                                                               valueOf(fields[1]),
+                                                               Integer.parseInt(fields[2]));
+        stream.setNode(node);
+        nodes.put(node.id(), node);
+        streams.put(node.id(), stream);
+        states.put(node.id(), State.ACTIVE);
+    }
+
+    // Processes an ECHO message from a peer controller node.
+    private void processEcho(TLVMessage message, TLVMessageStream tlvStream) {
+        // TODO: implement heart-beat refresh
+        log.info("Dealing with echoes...");
+    }
+
+    // Sends message to the specified stream.
+    private void send(TLVMessageStream stream, TLVMessage message) {
+        try {
+            stream.write(message);
+        } catch (IOException e) {
+            log.warn("Unable to send message to {}", stream.node().id());
+        }
+    }
+
+    // Creates a hello message to be sent to a peer controller node.
+    private TLVMessage createHello(DefaultControllerNode self) {
+        return new TLVMessage(HELLO_MSG, (self.id() + ":" + self.ip() + ":" + self.tcpPort()).getBytes());
+    }
+
+    // Sweeps through all controller nodes and attempts to open connection to
+    // those that presently do not have one.
+    private class ConnectionCustodian extends TimerTask {
+        @Override
+        public void run() {
+            for (DefaultControllerNode node : nodes.values()) {
+                if (node != self && !streams.containsKey(node.id())) {
+                    try {
+                        openConnection(node, findLeastUtilizedLoop());
+                    } catch (IOException e) {
+                        log.debug("Unable to connect", e);
+                    }
+                }
+            }
+        }
+    }
+
+    // Finds the least utilities IO loop.
+    private CommLoop findLeastUtilizedLoop() {
+        CommLoop leastUtilized = null;
+        int minCount = Integer.MAX_VALUE;
+        for (CommLoop loop : commLoops) {
+            int count = loop.streamCount();
+            if (count == 0) {
+                return loop;
+            }
+
+            if (count < minCount) {
+                leastUtilized = loop;
+                minCount = count;
+            }
+        }
+        return leastUtilized;
+    }
+}

+package org.onlab.onos.store.cluster.impl;
+
+import org.onlab.nio.AbstractMessage;
+
+import java.util.Objects;
+
+import static com.google.common.base.MoreObjects.toStringHelper;
+
+/**
+ * Base message for cluster-wide communications using TLVs.
+ */
+public class TLVMessage extends AbstractMessage {
+
+    private final int type;
+    private final byte[] data;
+
+    /**
+     * Creates an immutable TLV message.
+     *
+     * @param type   message type
+     * @param data   message data bytes
+     */
+    public TLVMessage(int type, byte[] data) {
+        this.length = data.length + TLVMessageStream.METADATA_LENGTH;
+        this.type = type;
+        this.data = data;
+    }
+
+    /**
+     * Returns the message type indicator.
+     *
+     * @return message type
+     */
+    public int type() {
+        return type;
+    }
+
+    /**
+     * Returns the data bytes.
+     *
+     * @return message data
+     */
+    public byte[] data() {
+        return data;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(type, data);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj == null || getClass() != obj.getClass()) {
+            return false;
+        }
+        final TLVMessage other = (TLVMessage) obj;
+        return Objects.equals(this.type, other.type) &&
+                Objects.equals(this.data, other.data);
+    }
+
+    @Override
+    public String toString() {
+        return toStringHelper(this).add("type", type).add("length", length).toString();
+    }
+
+}

+package org.onlab.onos.store.cluster.impl;
+
+import org.onlab.nio.IOLoop;
+import org.onlab.nio.MessageStream;
+import org.onlab.onos.cluster.DefaultControllerNode;
+
+import java.nio.ByteBuffer;
+import java.nio.channels.ByteChannel;
+
+import static com.google.common.base.Preconditions.checkState;
+
+/**
+ * Stream for transferring TLV messages between cluster members.
+ */
+public class TLVMessageStream extends MessageStream<TLVMessage> {
+
+    public static final int METADATA_LENGTH = 16; // 8 + 4 + 4
+
+    private static final int LENGTH_OFFSET = 12;
+    private static final long MARKER = 0xfeedcafecafefeedL;
+
+    private DefaultControllerNode node;
+
+    /**
+     * Creates a message stream associated with the specified IO loop and
+     * backed by the given byte channel.
+     *
+     * @param loop          IO loop
+     * @param byteChannel   backing byte channel
+     * @param bufferSize    size of the backing byte buffers
+     * @param maxIdleMillis maximum number of millis the stream can be idle
+     */
+    protected TLVMessageStream(IOLoop<TLVMessage, ?> loop, ByteChannel byteChannel,
+                               int bufferSize, int maxIdleMillis) {
+        super(loop, byteChannel, bufferSize, maxIdleMillis);
+    }
+
+    /**
+     * Returns the node with which this stream is associated.
+     *
+     * @return controller node
+     */
+    DefaultControllerNode node() {
+        return node;
+    }
+
+    /**
+     * Sets the node with which this stream is affiliated.
+     *
+     * @param node controller node
+     */
+    void setNode(DefaultControllerNode node) {
+        checkState(this.node == null, "Stream is already bound to a node");
+        this.node = node;
+    }
+
+    @Override
+    protected TLVMessage read(ByteBuffer buffer) {
+        // Do we have enough bytes to read the header? If not, bail.
+        if (buffer.remaining() < METADATA_LENGTH) {
+            return null;
+        }
+
+        // Peek at the length and if we have enough to read the entire message
+        // go ahead, otherwise bail.
+        int length = buffer.getInt(buffer.position() + LENGTH_OFFSET);
+        if (buffer.remaining() < length) {
+            return null;
+        }
+
+        // At this point, we have enough data to read a complete message.
+        long marker = buffer.getLong();
+        checkState(marker == MARKER, "Incorrect message marker");
+
+        int type = buffer.getInt();
+        length = buffer.getInt();
+
+        // TODO: add deserialization hook here
+        byte[] data = new byte[length - METADATA_LENGTH];
+        buffer.get(data);
+
+        return new TLVMessage(type, data);
+    }
+
+    @Override
+    protected void write(TLVMessage message, ByteBuffer buffer) {
+        buffer.putLong(MARKER);
+        buffer.putInt(message.type());
+        buffer.putInt(message.length());
+
+        // TODO: add serialization hook here
+        buffer.put(message.data());
+    }
+
+}

@@ -86,46 +86,48 @@ public class OnosDistributedDeviceStore
 
 
     @Override
     @Override
     public Iterable<Device> getDevices() {
     public Iterable<Device> getDevices() {
-        // TODO builder v.s. copyOf. Guava semms to be using copyOf?
-        // FIXME: synchronize.
         Builder<Device> builder = ImmutableSet.builder();
         Builder<Device> builder = ImmutableSet.builder();
-        for (VersionedValue<? extends Device> device : devices.values()) {
-            builder.add(device.entity());
+        synchronized (this) {
+            for (VersionedValue<Device> device : devices.values()) {
+                builder.add(device.entity());
+            }
+            return builder.build();
         }
         }
-        return builder.build();
     }
     }
 
 
     @Override
     @Override
     public Device getDevice(DeviceId deviceId) {
     public Device getDevice(DeviceId deviceId) {
-        return devices.get(deviceId).entity();
+        VersionedValue<Device> device = devices.get(deviceId);
+        checkArgument(device != null, DEVICE_NOT_FOUND, deviceId);
+        return device.entity();
     }
     }
 
 
     @Override
     @Override
     public DeviceEvent createOrUpdateDevice(ProviderId providerId, DeviceId deviceId,
     public DeviceEvent createOrUpdateDevice(ProviderId providerId, DeviceId deviceId,
                                             DeviceDescription deviceDescription) {
                                             DeviceDescription deviceDescription) {
-        Timestamp now = clockService.getTimestamp(deviceId);
+        Timestamp newTimestamp = clockService.getTimestamp(deviceId);
         VersionedValue<Device> device = devices.get(deviceId);
         VersionedValue<Device> device = devices.get(deviceId);
 
 
         if (device == null) {
         if (device == null) {
-            return createDevice(providerId, deviceId, deviceDescription, now);
+            return createDevice(providerId, deviceId, deviceDescription, newTimestamp);
         }
         }
 
 
-        checkState(now.compareTo(device.timestamp()) > 0,
+        checkState(newTimestamp.compareTo(device.timestamp()) > 0,
                 "Existing device has a timestamp in the future!");
                 "Existing device has a timestamp in the future!");
 
 
-        return updateDevice(providerId, device.entity(), deviceDescription, now);
+        return updateDevice(providerId, device.entity(), deviceDescription, newTimestamp);
     }
     }
 
 
     // Creates the device and returns the appropriate event if necessary.
     // Creates the device and returns the appropriate event if necessary.
     private DeviceEvent createDevice(ProviderId providerId, DeviceId deviceId,
     private DeviceEvent createDevice(ProviderId providerId, DeviceId deviceId,
                                      DeviceDescription desc, Timestamp timestamp) {
                                      DeviceDescription desc, Timestamp timestamp) {
-        DefaultDevice device = new DefaultDevice(providerId, deviceId, desc.type(),
+        Device device = new DefaultDevice(providerId, deviceId, desc.type(),
                                                  desc.manufacturer(),
                                                  desc.manufacturer(),
                                                  desc.hwVersion(), desc.swVersion(),
                                                  desc.hwVersion(), desc.swVersion(),
                                                  desc.serialNumber());
                                                  desc.serialNumber());
 
 
-        devices.put(deviceId, new VersionedValue<Device>(device, true, timestamp));
-        // FIXME: broadcast a message telling peers of a device event.
+        devices.put(deviceId, new VersionedValue<>(device, true, timestamp));
+        // TODO,FIXME: broadcast a message telling peers of a device event.
         return new DeviceEvent(DEVICE_ADDED, device, null);
         return new DeviceEvent(DEVICE_ADDED, device, null);
     }
     }
 
 
@@ -148,7 +150,7 @@ public class OnosDistributedDeviceStore
         }
         }
 
 
         // Otherwise merely attempt to change availability
         // Otherwise merely attempt to change availability
-        DefaultDevice updated = new DefaultDevice(providerId, device.id(),
+        Device updated = new DefaultDevice(providerId, device.id(),
                 desc.type(),
                 desc.type(),
                 desc.manufacturer(),
                 desc.manufacturer(),
                 desc.hwVersion(),
                 desc.hwVersion(),
@@ -196,18 +198,18 @@ public class OnosDistributedDeviceStore
             VersionedValue<Device> device = devices.get(deviceId);
             VersionedValue<Device> device = devices.get(deviceId);
             checkArgument(device != null, DEVICE_NOT_FOUND, deviceId);
             checkArgument(device != null, DEVICE_NOT_FOUND, deviceId);
             Map<PortNumber, VersionedValue<Port>> ports = getPortMap(deviceId);
             Map<PortNumber, VersionedValue<Port>> ports = getPortMap(deviceId);
-            Timestamp timestamp = clockService.getTimestamp(deviceId);
+            Timestamp newTimestamp = clockService.getTimestamp(deviceId);
 
 
             // Add new ports
             // Add new ports
             Set<PortNumber> processed = new HashSet<>();
             Set<PortNumber> processed = new HashSet<>();
             for (PortDescription portDescription : portDescriptions) {
             for (PortDescription portDescription : portDescriptions) {
                 VersionedValue<Port> port = ports.get(portDescription.portNumber());
                 VersionedValue<Port> port = ports.get(portDescription.portNumber());
                 if (port == null) {
                 if (port == null) {
-                    events.add(createPort(device, portDescription, ports, timestamp));
+                    events.add(createPort(device, portDescription, ports, newTimestamp));
                 }
                 }
-                checkState(timestamp.compareTo(port.timestamp()) > 0,
+                checkState(newTimestamp.compareTo(port.timestamp()) > 0,
                         "Existing port state has a timestamp in the future!");
                         "Existing port state has a timestamp in the future!");
-                events.add(updatePort(device, port, portDescription, ports, timestamp));
+                events.add(updatePort(device.entity(), port.entity(), portDescription, ports, newTimestamp));
                 processed.add(portDescription.portNumber());
                 processed.add(portDescription.portNumber());
             }
             }
 
 
@@ -233,19 +235,19 @@ public class OnosDistributedDeviceStore
     // Checks if the specified port requires update and if so, it replaces the
     // Checks if the specified port requires update and if so, it replaces the
     // existing entry in the map and returns corresponding event.
     // existing entry in the map and returns corresponding event.
     //@GuardedBy("this")
     //@GuardedBy("this")
-    private DeviceEvent updatePort(VersionedValue<Device> device, VersionedValue<Port> port,
+    private DeviceEvent updatePort(Device device, Port port,
                                    PortDescription portDescription,
                                    PortDescription portDescription,
                                    Map<PortNumber, VersionedValue<Port>> ports,
                                    Map<PortNumber, VersionedValue<Port>> ports,
                                    Timestamp timestamp) {
                                    Timestamp timestamp) {
-        if (port.entity().isEnabled() != portDescription.isEnabled()) {
+        if (port.isEnabled() != portDescription.isEnabled()) {
             VersionedValue<Port> updatedPort = new VersionedValue<Port>(
             VersionedValue<Port> updatedPort = new VersionedValue<Port>(
-                    new DefaultPort(device.entity(), portDescription.portNumber(),
+                    new DefaultPort(device, portDescription.portNumber(),
                                     portDescription.isEnabled()),
                                     portDescription.isEnabled()),
                     portDescription.isEnabled(),
                     portDescription.isEnabled(),
                     timestamp);
                     timestamp);
-            ports.put(port.entity().number(), updatedPort);
-            updatePortMap(device.entity().id(), ports);
-            return new DeviceEvent(PORT_UPDATED, device.entity(), updatedPort.entity());
+            ports.put(port.number(), updatedPort);
+            updatePortMap(device.id(), ports);
+            return new DeviceEvent(PORT_UPDATED, device, updatedPort.entity());
         }
         }
         return null;
         return null;
     }
     }
@@ -300,7 +302,7 @@ public class OnosDistributedDeviceStore
         Map<PortNumber, VersionedValue<Port>> ports = getPortMap(deviceId);
         Map<PortNumber, VersionedValue<Port>> ports = getPortMap(deviceId);
         VersionedValue<Port> port = ports.get(portDescription.portNumber());
         VersionedValue<Port> port = ports.get(portDescription.portNumber());
         Timestamp timestamp = clockService.getTimestamp(deviceId);
         Timestamp timestamp = clockService.getTimestamp(deviceId);
-        return updatePort(device, port, portDescription, ports, timestamp);
+        return updatePort(device.entity(), port.entity(), portDescription, ports, timestamp);
     }
     }
 
 
     @Override
     @Override

+package org.onlab.onos.store.link.impl;
+
+import static org.onlab.onos.net.Link.Type.DIRECT;
+import static org.onlab.onos.net.Link.Type.INDIRECT;
+import static org.onlab.onos.net.link.LinkEvent.Type.LINK_ADDED;
+import static org.onlab.onos.net.link.LinkEvent.Type.LINK_REMOVED;
+import static org.onlab.onos.net.link.LinkEvent.Type.LINK_UPDATED;
+import static org.slf4j.LoggerFactory.getLogger;
+
+import java.util.HashSet;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.apache.felix.scr.annotations.Service;
+import org.onlab.onos.net.ConnectPoint;
+import org.onlab.onos.net.DefaultLink;
+import org.onlab.onos.net.DeviceId;
+import org.onlab.onos.net.Link;
+import org.onlab.onos.net.LinkKey;
+import org.onlab.onos.net.link.LinkDescription;
+import org.onlab.onos.net.link.LinkEvent;
+import org.onlab.onos.net.link.LinkStore;
+import org.onlab.onos.net.link.LinkStoreDelegate;
+import org.onlab.onos.net.provider.ProviderId;
+import org.onlab.onos.store.AbstractStore;
+import org.onlab.onos.store.ClockService;
+import org.onlab.onos.store.Timestamp;
+import org.onlab.onos.store.device.impl.VersionedValue;
+import org.slf4j.Logger;
+
+import com.google.common.collect.HashMultimap;
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Multimap;
+import com.google.common.collect.ImmutableSet.Builder;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Preconditions.checkState;
+
+/**
+ * Manages inventory of infrastructure links using a protocol that takes into consideration
+ * the order in which events occur.
+ */
+// FIXME: This does not yet implement the full protocol.
+// The full protocol requires the sender of LLDP message to include the
+// version information of src device/port and the receiver to
+// take that into account when figuring out if a more recent src
+// device/port down event renders the link discovery obsolete.
+@Component(immediate = true)
+@Service
+public class OnosDistributedLinkStore
+    extends AbstractStore<LinkEvent, LinkStoreDelegate>
+    implements LinkStore {
+
+    private final Logger log = getLogger(getClass());
+
+    // Link inventory
+    private ConcurrentMap<LinkKey, VersionedValue<Link>> links;
+
+    public static final String LINK_NOT_FOUND = "Link between %s and %s not found";
+
+    // TODO synchronize?
+    // Egress and ingress link sets
+    private final Multimap<DeviceId, VersionedValue<Link>> srcLinks = HashMultimap.create();
+    private final Multimap<DeviceId, VersionedValue<Link>> dstLinks = HashMultimap.create();
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected ClockService clockService;
+
+    @Activate
+    public void activate() {
+
+        links = new ConcurrentHashMap<>();
+
+        log.info("Started");
+    }
+
+    @Deactivate
+    public void deactivate() {
+        log.info("Stopped");
+    }
+
+    @Override
+    public int getLinkCount() {
+        return links.size();
+    }
+
+    @Override
+    public Iterable<Link> getLinks() {
+        Builder<Link> builder = ImmutableSet.builder();
+        synchronized (this) {
+            for (VersionedValue<Link> link : links.values()) {
+                builder.add(link.entity());
+            }
+            return builder.build();
+        }
+    }
+
+    @Override
+    public Set<Link> getDeviceEgressLinks(DeviceId deviceId) {
+        Set<VersionedValue<Link>> egressLinks = ImmutableSet.copyOf(srcLinks.get(deviceId));
+        Set<Link> rawEgressLinks = new HashSet<>();
+        for (VersionedValue<Link> link : egressLinks) {
+            rawEgressLinks.add(link.entity());
+        }
+        return rawEgressLinks;
+    }
+
+    @Override
+    public Set<Link> getDeviceIngressLinks(DeviceId deviceId) {
+        Set<VersionedValue<Link>> ingressLinks = ImmutableSet.copyOf(dstLinks.get(deviceId));
+        Set<Link> rawIngressLinks = new HashSet<>();
+        for (VersionedValue<Link> link : ingressLinks) {
+            rawIngressLinks.add(link.entity());
+        }
+        return rawIngressLinks;
+    }
+
+    @Override
+    public Link getLink(ConnectPoint src, ConnectPoint dst) {
+        VersionedValue<Link> link = links.get(new LinkKey(src, dst));
+        checkArgument(link != null, "LINK_NOT_FOUND", src, dst);
+        return link.entity();
+    }
+
+    @Override
+    public Set<Link> getEgressLinks(ConnectPoint src) {
+        Set<Link> egressLinks = new HashSet<>();
+        for (VersionedValue<Link> link : srcLinks.get(src.deviceId())) {
+            if (link.entity().src().equals(src)) {
+                egressLinks.add(link.entity());
+            }
+        }
+        return egressLinks;
+    }
+
+    @Override
+    public Set<Link> getIngressLinks(ConnectPoint dst) {
+        Set<Link> ingressLinks = new HashSet<>();
+        for (VersionedValue<Link> link : dstLinks.get(dst.deviceId())) {
+            if (link.entity().dst().equals(dst)) {
+                ingressLinks.add(link.entity());
+            }
+        }
+        return ingressLinks;
+    }
+
+    @Override
+    public LinkEvent createOrUpdateLink(ProviderId providerId,
+                                        LinkDescription linkDescription) {
+
+        final DeviceId destinationDeviceId = linkDescription.dst().deviceId();
+        final Timestamp newTimestamp = clockService.getTimestamp(destinationDeviceId);
+
+        LinkKey key = new LinkKey(linkDescription.src(), linkDescription.dst());
+        VersionedValue<Link> link = links.get(key);
+        if (link == null) {
+            return createLink(providerId, key, linkDescription, newTimestamp);
+        }
+
+        checkState(newTimestamp.compareTo(link.timestamp()) > 0,
+                "Existing Link has a timestamp in the future!");
+
+        return updateLink(providerId, link, key, linkDescription, newTimestamp);
+    }
+
+    // Creates and stores the link and returns the appropriate event.
+    private LinkEvent createLink(ProviderId providerId, LinkKey key,
+            LinkDescription linkDescription, Timestamp timestamp) {
+        VersionedValue<Link> link = new VersionedValue<Link>(new DefaultLink(providerId, key.src(), key.dst(),
+                linkDescription.type()), true, timestamp);
+        synchronized (this) {
+            links.put(key, link);
+            addNewLink(link, timestamp);
+        }
+        // FIXME: notify peers.
+        return new LinkEvent(LINK_ADDED, link.entity());
+    }
+
+    // update Egress and ingress link sets
+    private void addNewLink(VersionedValue<Link> link, Timestamp timestamp) {
+        Link rawLink = link.entity();
+        synchronized (this) {
+            srcLinks.put(rawLink.src().deviceId(), link);
+            dstLinks.put(rawLink.dst().deviceId(), link);
+        }
+    }
+
+    // Updates, if necessary the specified link and returns the appropriate event.
+    private LinkEvent updateLink(ProviderId providerId, VersionedValue<Link> existingLink,
+                                 LinkKey key, LinkDescription linkDescription, Timestamp timestamp) {
+        // FIXME confirm Link update condition is OK
+        if (existingLink.entity().type() == INDIRECT && linkDescription.type() == DIRECT) {
+            synchronized (this) {
+
+                VersionedValue<Link> updatedLink = new VersionedValue<Link>(
+                        new DefaultLink(providerId, existingLink.entity().src(), existingLink.entity().dst(),
+                                        linkDescription.type()), true, timestamp);
+                links.replace(key, existingLink, updatedLink);
+
+                replaceLink(existingLink, updatedLink);
+                // FIXME: notify peers.
+                return new LinkEvent(LINK_UPDATED, updatedLink.entity());
+            }
+        }
+        return null;
+    }
+
+    // update Egress and ingress link sets
+    private void replaceLink(VersionedValue<Link> current, VersionedValue<Link> updated) {
+        synchronized (this) {
+            srcLinks.remove(current.entity().src().deviceId(), current);
+            dstLinks.remove(current.entity().dst().deviceId(), current);
+
+            srcLinks.put(current.entity().src().deviceId(), updated);
+            dstLinks.put(current.entity().dst().deviceId(), updated);
+        }
+    }
+
+    @Override
+    public LinkEvent removeLink(ConnectPoint src, ConnectPoint dst) {
+        synchronized (this) {
+            LinkKey key = new LinkKey(src, dst);
+            VersionedValue<Link> link = links.remove(key);
+            if (link != null) {
+                removeLink(link);
+                // notify peers
+                return new LinkEvent(LINK_REMOVED, link.entity());
+            }
+            return null;
+        }
+    }
+
+    // update Egress and ingress link sets
+    private void removeLink(VersionedValue<Link> link) {
+        synchronized (this) {
+            srcLinks.remove(link.entity().src().deviceId(), link);
+            dstLinks.remove(link.entity().dst().deviceId(), link);
+        }
+    }
+}

@@ -49,6 +49,7 @@ public class DistributedClusterStore
     private final MembershipListener listener = new InternalMembershipListener();
     private final MembershipListener listener = new InternalMembershipListener();
     private final Map<NodeId, State> states = new ConcurrentHashMap<>();
     private final Map<NodeId, State> states = new ConcurrentHashMap<>();
 
 
+    @Override
     @Activate
     @Activate
     public void activate() {
     public void activate() {
         super.activate();
         super.activate();
@@ -56,9 +57,9 @@ public class DistributedClusterStore
 
 
         rawNodes = theInstance.getMap("nodes");
         rawNodes = theInstance.getMap("nodes");
         OptionalCacheLoader<NodeId, DefaultControllerNode> nodeLoader
         OptionalCacheLoader<NodeId, DefaultControllerNode> nodeLoader
-                = new OptionalCacheLoader<>(storeService, rawNodes);
+                = new OptionalCacheLoader<>(kryoSerializationService, rawNodes);
         nodes = new AbsentInvalidatingLoadingCache<>(newBuilder().build(nodeLoader));
         nodes = new AbsentInvalidatingLoadingCache<>(newBuilder().build(nodeLoader));
-        rawNodes.addEntryListener(new RemoteEventHandler<>(nodes), true);
+        rawNodes.addEntryListener(new RemoteCacheEventHandler<>(nodes), true);
 
 
         loadClusterNodes();
         loadClusterNodes();
 
 
@@ -68,7 +69,7 @@ public class DistributedClusterStore
     // Loads the initial set of cluster nodes
     // Loads the initial set of cluster nodes
     private void loadClusterNodes() {
     private void loadClusterNodes() {
         for (Member member : theInstance.getCluster().getMembers()) {
         for (Member member : theInstance.getCluster().getMembers()) {
-            addMember(member);
+            addNode(node(member));
         }
         }
     }
     }
 
 
@@ -104,6 +105,11 @@ public class DistributedClusterStore
     }
     }
 
 
     @Override
     @Override
+    public ControllerNode addNode(NodeId nodeId, IpPrefix ip, int tcpPort) {
+        return addNode(new DefaultControllerNode(nodeId, ip, tcpPort));
+    }
+
+    @Override
     public void removeNode(NodeId nodeId) {
     public void removeNode(NodeId nodeId) {
         synchronized (this) {
         synchronized (this) {
             rawNodes.remove(serialize(nodeId));
             rawNodes.remove(serialize(nodeId));
@@ -112,8 +118,7 @@ public class DistributedClusterStore
     }
     }
 
 
     // Adds a new node based on the specified member
     // Adds a new node based on the specified member
-    private synchronized ControllerNode addMember(Member member) {
-        DefaultControllerNode node = node(member);
+    private synchronized ControllerNode addNode(DefaultControllerNode node) {
         rawNodes.put(serialize(node.id()), serialize(node));
         rawNodes.put(serialize(node.id()), serialize(node));
         nodes.put(node.id(), Optional.of(node));
         nodes.put(node.id(), Optional.of(node));
         states.put(node.id(), State.ACTIVE);
         states.put(node.id(), State.ACTIVE);
@@ -136,7 +141,7 @@ public class DistributedClusterStore
         @Override
         @Override
         public void memberAdded(MembershipEvent membershipEvent) {
         public void memberAdded(MembershipEvent membershipEvent) {
             log.info("Member {} added", membershipEvent.getMember());
             log.info("Member {} added", membershipEvent.getMember());
-            ControllerNode node = addMember(membershipEvent.getMember());
+            ControllerNode node = addNode(node(membershipEvent.getMember()));
             notifyDelegate(new ClusterEvent(INSTANCE_ACTIVATED, node));
             notifyDelegate(new ClusterEvent(INSTANCE_ACTIVATED, node));
         }
         }
 
 

@@ -52,7 +52,7 @@ implements MastershipStore {
 
 
         rawMasters = theInstance.getMap("masters");
         rawMasters = theInstance.getMap("masters");
         OptionalCacheLoader<DeviceId, NodeId> nodeLoader
         OptionalCacheLoader<DeviceId, NodeId> nodeLoader
-        = new OptionalCacheLoader<>(storeService, rawMasters);
+        = new OptionalCacheLoader<>(kryoSerializationService, rawMasters);
         masters = new AbsentInvalidatingLoadingCache<>(newBuilder().build(nodeLoader));
         masters = new AbsentInvalidatingLoadingCache<>(newBuilder().build(nodeLoader));
         rawMasters.addEntryListener(new RemoteMasterShipEventHandler(masters), true);
         rawMasters.addEntryListener(new RemoteMasterShipEventHandler(masters), true);
 
 
@@ -123,7 +123,7 @@ implements MastershipStore {
         return null;
         return null;
     }
     }
 
 
-    private class RemoteMasterShipEventHandler extends RemoteEventHandler<DeviceId, NodeId> {
+    private class RemoteMasterShipEventHandler extends RemoteCacheEventHandler<DeviceId, NodeId> {
         public RemoteMasterShipEventHandler(LoadingCache<DeviceId, Optional<NodeId>> cache) {
         public RemoteMasterShipEventHandler(LoadingCache<DeviceId, Optional<NodeId>> cache) {
             super(cache);
             super(cache);
         }
         }

@@ -6,6 +6,7 @@ import com.hazelcast.core.EntryAdapter;
 import com.hazelcast.core.EntryEvent;
 import com.hazelcast.core.EntryEvent;
 import com.hazelcast.core.HazelcastInstance;
 import com.hazelcast.core.HazelcastInstance;
 import com.hazelcast.core.MapEvent;
 import com.hazelcast.core.MapEvent;
+import com.hazelcast.core.Member;
 
 
 import org.apache.felix.scr.annotations.Activate;
 import org.apache.felix.scr.annotations.Activate;
 import org.apache.felix.scr.annotations.Component;
 import org.apache.felix.scr.annotations.Component;
@@ -14,6 +15,7 @@ import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.onlab.onos.event.Event;
 import org.onlab.onos.event.Event;
 import org.onlab.onos.store.AbstractStore;
 import org.onlab.onos.store.AbstractStore;
 import org.onlab.onos.store.StoreDelegate;
 import org.onlab.onos.store.StoreDelegate;
+import org.onlab.onos.store.serializers.KryoSerializationService;
 import org.slf4j.Logger;
 import org.slf4j.Logger;
 
 
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkNotNull;
@@ -31,6 +33,9 @@ public abstract class AbstractHazelcastStore<E extends Event, D extends StoreDel
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected StoreService storeService;
     protected StoreService storeService;
 
 
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected KryoSerializationService kryoSerializationService;
+
     protected HazelcastInstance theInstance;
     protected HazelcastInstance theInstance;
 
 
     @Activate
     @Activate
@@ -45,7 +50,7 @@ public abstract class AbstractHazelcastStore<E extends Event, D extends StoreDel
      * @return serialized object
      * @return serialized object
      */
      */
     protected byte[] serialize(Object obj) {
     protected byte[] serialize(Object obj) {
-        return storeService.serialize(obj);
+        return kryoSerializationService.serialize(obj);
     }
     }
 
 
     /**
     /**
@@ -56,7 +61,7 @@ public abstract class AbstractHazelcastStore<E extends Event, D extends StoreDel
      * @return deserialized object
      * @return deserialized object
      */
      */
     protected <T> T deserialize(byte[] bytes) {
     protected <T> T deserialize(byte[] bytes) {
-        return storeService.deserialize(bytes);
+        return kryoSerializationService.deserialize(bytes);
     }
     }
 
 
 
 
@@ -66,8 +71,9 @@ public abstract class AbstractHazelcastStore<E extends Event, D extends StoreDel
      * @param <K> IMap key type after deserialization
      * @param <K> IMap key type after deserialization
      * @param <V> IMap value type after deserialization
      * @param <V> IMap value type after deserialization
      */
      */
-    public class RemoteEventHandler<K, V> extends EntryAdapter<byte[], byte[]> {
+    public class RemoteCacheEventHandler<K, V> extends EntryAdapter<byte[], byte[]> {
 
 
+        private final Member localMember;
         private LoadingCache<K, Optional<V>> cache;
         private LoadingCache<K, Optional<V>> cache;
 
 
         /**
         /**
@@ -75,17 +81,26 @@ public abstract class AbstractHazelcastStore<E extends Event, D extends StoreDel
          *
          *
          * @param cache cache to update
          * @param cache cache to update
          */
          */
-        public RemoteEventHandler(LoadingCache<K, Optional<V>> cache) {
+        public RemoteCacheEventHandler(LoadingCache<K, Optional<V>> cache) {
+            this.localMember = theInstance.getCluster().getLocalMember();
             this.cache = checkNotNull(cache);
             this.cache = checkNotNull(cache);
         }
         }
 
 
         @Override
         @Override
         public void mapCleared(MapEvent event) {
         public void mapCleared(MapEvent event) {
+            if (localMember.equals(event.getMember())) {
+                // ignore locally triggered event
+                return;
+            }
             cache.invalidateAll();
             cache.invalidateAll();
         }
         }
 
 
         @Override
         @Override
         public void entryAdded(EntryEvent<byte[], byte[]> event) {
         public void entryAdded(EntryEvent<byte[], byte[]> event) {
+            if (localMember.equals(event.getMember())) {
+                // ignore locally triggered event
+                return;
+            }
             K key = deserialize(event.getKey());
             K key = deserialize(event.getKey());
             V newVal = deserialize(event.getValue());
             V newVal = deserialize(event.getValue());
             Optional<V> newValue = Optional.of(newVal);
             Optional<V> newValue = Optional.of(newVal);
@@ -95,6 +110,10 @@ public abstract class AbstractHazelcastStore<E extends Event, D extends StoreDel
 
 
         @Override
         @Override
         public void entryUpdated(EntryEvent<byte[], byte[]> event) {
         public void entryUpdated(EntryEvent<byte[], byte[]> event) {
+            if (localMember.equals(event.getMember())) {
+                // ignore locally triggered event
+                return;
+            }
             K key = deserialize(event.getKey());
             K key = deserialize(event.getKey());
             V oldVal = deserialize(event.getOldValue());
             V oldVal = deserialize(event.getOldValue());
             Optional<V> oldValue = Optional.fromNullable(oldVal);
             Optional<V> oldValue = Optional.fromNullable(oldVal);
@@ -106,6 +125,10 @@ public abstract class AbstractHazelcastStore<E extends Event, D extends StoreDel
 
 
         @Override
         @Override
         public void entryRemoved(EntryEvent<byte[], byte[]> event) {
         public void entryRemoved(EntryEvent<byte[], byte[]> event) {
+            if (localMember.equals(event.getMember())) {
+                // ignore locally triggered event
+                return;
+            }
             K key = deserialize(event.getKey());
             K key = deserialize(event.getKey());
             V val = deserialize(event.getOldValue());
             V val = deserialize(event.getOldValue());
             cache.invalidate(key);
             cache.invalidate(key);
@@ -141,4 +164,80 @@ public abstract class AbstractHazelcastStore<E extends Event, D extends StoreDel
         }
         }
     }
     }
 
 
+    /**
+     * Distributed object remote event entry listener.
+     *
+     * @param <K> Entry key type after deserialization
+     * @param <V> Entry value type after deserialization
+     */
+    public class RemoteEventHandler<K, V> extends EntryAdapter<byte[], byte[]> {
+
+        private final Member localMember;
+
+        public RemoteEventHandler() {
+            this.localMember = theInstance.getCluster().getLocalMember();
+        }
+        @Override
+        public void entryAdded(EntryEvent<byte[], byte[]> event) {
+            if (localMember.equals(event.getMember())) {
+                // ignore locally triggered event
+                return;
+            }
+            K key = deserialize(event.getKey());
+            V newVal = deserialize(event.getValue());
+            onAdd(key, newVal);
+        }
+
+        @Override
+        public void entryRemoved(EntryEvent<byte[], byte[]> event) {
+            if (localMember.equals(event.getMember())) {
+                // ignore locally triggered event
+                return;
+            }
+            K key = deserialize(event.getKey());
+            V val = deserialize(event.getValue());
+            onRemove(key, val);
+        }
+
+        @Override
+        public void entryUpdated(EntryEvent<byte[], byte[]> event) {
+            if (localMember.equals(event.getMember())) {
+                // ignore locally triggered event
+                return;
+            }
+            K key = deserialize(event.getKey());
+            V oldVal = deserialize(event.getOldValue());
+            V newVal = deserialize(event.getValue());
+            onUpdate(key, oldVal, newVal);
+        }
+
+        /**
+         * Remote entry addition hook.
+         *
+         * @param key    new key
+         * @param newVal new value
+         */
+        protected void onAdd(K key, V newVal) {
+        }
+
+        /**
+         * Remote entry update hook.
+         *
+         * @param key    new key
+         * @param oldValue old value
+         * @param newVal new value
+         */
+        protected void onUpdate(K key, V oldValue, V newVal) {
+        }
+
+        /**
+         * Remote entry remove hook.
+         *
+         * @param key new key
+         * @param val old value
+         */
+        protected void onRemove(K key, V val) {
+        }
+    }
+
 }
 }

@@ -2,6 +2,8 @@ package org.onlab.onos.store.common;
 
 
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkNotNull;
 
 
+import org.onlab.onos.store.serializers.KryoSerializationService;
+
 import com.google.common.base.Optional;
 import com.google.common.base.Optional;
 import com.google.common.cache.CacheLoader;
 import com.google.common.cache.CacheLoader;
 import com.hazelcast.core.IMap;
 import com.hazelcast.core.IMap;
@@ -16,28 +18,28 @@ import com.hazelcast.core.IMap;
 public final class OptionalCacheLoader<K, V> extends
 public final class OptionalCacheLoader<K, V> extends
         CacheLoader<K, Optional<V>> {
         CacheLoader<K, Optional<V>> {
 
 
-    private final StoreService storeService;
+    private final KryoSerializationService kryoSerializationService;
     private IMap<byte[], byte[]> rawMap;
     private IMap<byte[], byte[]> rawMap;
 
 
     /**
     /**
      * Constructor.
      * Constructor.
      *
      *
-     * @param storeService to use for serialization
+     * @param kryoSerializationService to use for serialization
      * @param rawMap underlying IMap
      * @param rawMap underlying IMap
      */
      */
-    public OptionalCacheLoader(StoreService storeService, IMap<byte[], byte[]> rawMap) {
-        this.storeService = checkNotNull(storeService);
+    public OptionalCacheLoader(KryoSerializationService kryoSerializationService, IMap<byte[], byte[]> rawMap) {
+        this.kryoSerializationService = checkNotNull(kryoSerializationService);
         this.rawMap = checkNotNull(rawMap);
         this.rawMap = checkNotNull(rawMap);
     }
     }
 
 
     @Override
     @Override
     public Optional<V> load(K key) throws Exception {
     public Optional<V> load(K key) throws Exception {
-        byte[] keyBytes = storeService.serialize(key);
+        byte[] keyBytes = kryoSerializationService.serialize(key);
         byte[] valBytes = rawMap.get(keyBytes);
         byte[] valBytes = rawMap.get(keyBytes);
         if (valBytes == null) {
         if (valBytes == null) {
             return Optional.absent();
             return Optional.absent();
         }
         }
-        V dev = storeService.deserialize(valBytes);
+        V dev = kryoSerializationService.deserialize(valBytes);
         return Optional.of(dev);
         return Optional.of(dev);
     }
     }
 }
 }

@@ -5,46 +5,14 @@ import com.hazelcast.config.FileSystemXmlConfig;
 import com.hazelcast.core.Hazelcast;
 import com.hazelcast.core.Hazelcast;
 import com.hazelcast.core.HazelcastInstance;
 import com.hazelcast.core.HazelcastInstance;
 
 
-import de.javakaffee.kryoserializers.URISerializer;
-
 import org.apache.felix.scr.annotations.Activate;
 import org.apache.felix.scr.annotations.Activate;
 import org.apache.felix.scr.annotations.Component;
 import org.apache.felix.scr.annotations.Component;
 import org.apache.felix.scr.annotations.Deactivate;
 import org.apache.felix.scr.annotations.Deactivate;
 import org.apache.felix.scr.annotations.Service;
 import org.apache.felix.scr.annotations.Service;
-import org.onlab.onos.cluster.ControllerNode;
-import org.onlab.onos.cluster.DefaultControllerNode;
-import org.onlab.onos.cluster.NodeId;
-import org.onlab.onos.net.ConnectPoint;
-import org.onlab.onos.net.DefaultDevice;
-import org.onlab.onos.net.DefaultLink;
-import org.onlab.onos.net.DefaultPort;
-import org.onlab.onos.net.Device;
-import org.onlab.onos.net.DeviceId;
-import org.onlab.onos.net.Element;
-import org.onlab.onos.net.Link;
-import org.onlab.onos.net.LinkKey;
-import org.onlab.onos.net.MastershipRole;
-import org.onlab.onos.net.Port;
-import org.onlab.onos.net.PortNumber;
-import org.onlab.onos.net.provider.ProviderId;
-import org.onlab.onos.store.serializers.ConnectPointSerializer;
-import org.onlab.onos.store.serializers.DefaultLinkSerializer;
-import org.onlab.onos.store.serializers.DefaultPortSerializer;
-import org.onlab.onos.store.serializers.DeviceIdSerializer;
-import org.onlab.onos.store.serializers.IpPrefixSerializer;
-import org.onlab.onos.store.serializers.LinkKeySerializer;
-import org.onlab.onos.store.serializers.NodeIdSerializer;
-import org.onlab.onos.store.serializers.PortNumberSerializer;
-import org.onlab.onos.store.serializers.ProviderIdSerializer;
-import org.onlab.packet.IpPrefix;
-import org.onlab.util.KryoPool;
 import org.slf4j.Logger;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.slf4j.LoggerFactory;
 
 
 import java.io.FileNotFoundException;
 import java.io.FileNotFoundException;
-import java.net.URI;
-import java.util.ArrayList;
-import java.util.HashMap;
 
 
 /**
 /**
  * Auxiliary bootstrap of distributed store.
  * Auxiliary bootstrap of distributed store.
@@ -58,55 +26,18 @@ public class StoreManager implements StoreService {
     private final Logger log = LoggerFactory.getLogger(getClass());
     private final Logger log = LoggerFactory.getLogger(getClass());
 
 
     protected HazelcastInstance instance;
     protected HazelcastInstance instance;
-    private KryoPool serializerPool;
-
 
 
     @Activate
     @Activate
     public void activate() {
     public void activate() {
         try {
         try {
             Config config = new FileSystemXmlConfig(HAZELCAST_XML_FILE);
             Config config = new FileSystemXmlConfig(HAZELCAST_XML_FILE);
             instance = Hazelcast.newHazelcastInstance(config);
             instance = Hazelcast.newHazelcastInstance(config);
-            setupKryoPool();
             log.info("Started");
             log.info("Started");
         } catch (FileNotFoundException e) {
         } catch (FileNotFoundException e) {
             log.error("Unable to configure Hazelcast", e);
             log.error("Unable to configure Hazelcast", e);
         }
         }
     }
     }
 
 
-    /**
-     * Sets up the common serialzers pool.
-     */
-    protected void setupKryoPool() {
-        // FIXME Slice out types used in common to separate pool/namespace.
-        serializerPool = KryoPool.newBuilder()
-                .register(ArrayList.class,
-                          HashMap.class,
-
-                          ControllerNode.State.class,
-                          Device.Type.class,
-
-                          DefaultControllerNode.class,
-                          DefaultDevice.class,
-                          MastershipRole.class,
-                          Port.class,
-                          Element.class,
-
-                          Link.Type.class
-                )
-                .register(IpPrefix.class, new IpPrefixSerializer())
-                .register(URI.class, new URISerializer())
-                .register(NodeId.class, new NodeIdSerializer())
-                .register(ProviderId.class, new ProviderIdSerializer())
-                .register(DeviceId.class, new DeviceIdSerializer())
-                .register(PortNumber.class, new PortNumberSerializer())
-                .register(DefaultPort.class, new DefaultPortSerializer())
-                .register(LinkKey.class, new LinkKeySerializer())
-                .register(ConnectPoint.class, new ConnectPointSerializer())
-                .register(DefaultLink.class, new DefaultLinkSerializer())
-                .build()
-                .populate(10);
-    }
-
     @Deactivate
     @Deactivate
     public void deactivate() {
     public void deactivate() {
         instance.shutdown();
         instance.shutdown();
@@ -118,18 +49,4 @@ public class StoreManager implements StoreService {
         return instance;
         return instance;
     }
     }
 
 
-
-    @Override
-    public byte[] serialize(final Object obj) {
-        return serializerPool.serialize(obj);
-    }
-
-    @Override
-    public <T> T deserialize(final byte[] bytes) {
-        if (bytes == null) {
-            return null;
-        }
-        return serializerPool.deserialize(bytes);
-    }
-
 }
 }

@@ -15,22 +15,4 @@ public interface StoreService {
      */
      */
     HazelcastInstance getHazelcastInstance();
     HazelcastInstance getHazelcastInstance();
 
 
-    /**
-     * Serializes the specified object into bytes using one of the
-     * pre-registered serializers.
-     *
-     * @param obj object to be serialized
-     * @return serialized bytes
-     */
-    public byte[] serialize(final Object obj);
-
-    /**
-     * Deserializes the specified bytes into an object using one of the
-     * pre-registered serializers.
-     *
-     * @param bytes bytes to be deserialized
-     * @return deserialized object
-     */
-    public <T> T deserialize(final byte[] bytes);
-
 }
 }

@@ -46,9 +46,8 @@ public class TestStoreManager extends StoreManager {
         this.instance = instance;
         this.instance = instance;
     }
     }
 
 
-    // Hazelcast setup removed from original code.
     @Override
     @Override
     public void activate() {
     public void activate() {
-        setupKryoPool();
+        // Hazelcast setup removed from original code.
     }
     }
 }
 }

@@ -72,6 +72,10 @@ public class DistributedDeviceStore
     private IMap<byte[], byte[]> rawDevicePorts;
     private IMap<byte[], byte[]> rawDevicePorts;
     private LoadingCache<DeviceId, Optional<Map<PortNumber, Port>>> devicePorts;
     private LoadingCache<DeviceId, Optional<Map<PortNumber, Port>>> devicePorts;
 
 
+    private String devicesListener;
+
+    private String portsListener;
+
     @Override
     @Override
     @Activate
     @Activate
     public void activate() {
     public void activate() {
@@ -83,20 +87,20 @@ public class DistributedDeviceStore
         // TODO decide on Map name scheme to avoid collision
         // TODO decide on Map name scheme to avoid collision
         rawDevices = theInstance.getMap("devices");
         rawDevices = theInstance.getMap("devices");
         final OptionalCacheLoader<DeviceId, DefaultDevice> deviceLoader
         final OptionalCacheLoader<DeviceId, DefaultDevice> deviceLoader
-                = new OptionalCacheLoader<>(storeService, rawDevices);
+                = new OptionalCacheLoader<>(kryoSerializationService, rawDevices);
         devices = new AbsentInvalidatingLoadingCache<>(newBuilder().build(deviceLoader));
         devices = new AbsentInvalidatingLoadingCache<>(newBuilder().build(deviceLoader));
         // refresh/populate cache based on notification from other instance
         // refresh/populate cache based on notification from other instance
-        rawDevices.addEntryListener(new RemoteDeviceEventHandler(devices), includeValue);
+        devicesListener = rawDevices.addEntryListener(new RemoteDeviceEventHandler(devices), includeValue);
 
 
         // TODO cache availableDevices
         // TODO cache availableDevices
         availableDevices = theInstance.getSet("availableDevices");
         availableDevices = theInstance.getSet("availableDevices");
 
 
         rawDevicePorts = theInstance.getMap("devicePorts");
         rawDevicePorts = theInstance.getMap("devicePorts");
         final OptionalCacheLoader<DeviceId, Map<PortNumber, Port>> devicePortLoader
         final OptionalCacheLoader<DeviceId, Map<PortNumber, Port>> devicePortLoader
-                = new OptionalCacheLoader<>(storeService, rawDevicePorts);
+                = new OptionalCacheLoader<>(kryoSerializationService, rawDevicePorts);
         devicePorts = new AbsentInvalidatingLoadingCache<>(newBuilder().build(devicePortLoader));
         devicePorts = new AbsentInvalidatingLoadingCache<>(newBuilder().build(devicePortLoader));
         // refresh/populate cache based on notification from other instance
         // refresh/populate cache based on notification from other instance
-        rawDevicePorts.addEntryListener(new RemotePortEventHandler(devicePorts), includeValue);
+        portsListener = rawDevicePorts.addEntryListener(new RemotePortEventHandler(devicePorts), includeValue);
 
 
         loadDeviceCache();
         loadDeviceCache();
         loadDevicePortsCache();
         loadDevicePortsCache();
@@ -106,6 +110,8 @@ public class DistributedDeviceStore
 
 
     @Deactivate
     @Deactivate
     public void deactivate() {
     public void deactivate() {
+        rawDevicePorts.removeEntryListener(portsListener);
+        rawDevices.removeEntryListener(devicesListener);
         log.info("Stopped");
         log.info("Stopped");
     }
     }
 
 
@@ -354,7 +360,7 @@ public class DistributedDeviceStore
         }
         }
     }
     }
 
 
-    private class RemoteDeviceEventHandler extends RemoteEventHandler<DeviceId, DefaultDevice> {
+    private class RemoteDeviceEventHandler extends RemoteCacheEventHandler<DeviceId, DefaultDevice> {
         public RemoteDeviceEventHandler(LoadingCache<DeviceId, Optional<DefaultDevice>> cache) {
         public RemoteDeviceEventHandler(LoadingCache<DeviceId, Optional<DefaultDevice>> cache) {
             super(cache);
             super(cache);
         }
         }
@@ -375,7 +381,7 @@ public class DistributedDeviceStore
         }
         }
     }
     }
 
 
-    private class RemotePortEventHandler extends RemoteEventHandler<DeviceId, Map<PortNumber, Port>> {
+    private class RemotePortEventHandler extends RemoteCacheEventHandler<DeviceId, Map<PortNumber, Port>> {
         public RemotePortEventHandler(LoadingCache<DeviceId, Optional<Map<PortNumber, Port>>> cache) {
         public RemotePortEventHandler(LoadingCache<DeviceId, Optional<Map<PortNumber, Port>>> cache) {
             super(cache);
             super(cache);
         }
         }

@@ -58,6 +58,8 @@ public class DistributedLinkStore
     private final Multimap<DeviceId, Link> srcLinks = HashMultimap.create();
     private final Multimap<DeviceId, Link> srcLinks = HashMultimap.create();
     private final Multimap<DeviceId, Link> dstLinks = HashMultimap.create();
     private final Multimap<DeviceId, Link> dstLinks = HashMultimap.create();
 
 
+    private String linksListener;
+
     @Override
     @Override
     @Activate
     @Activate
     public void activate() {
     public void activate() {
@@ -68,10 +70,10 @@ public class DistributedLinkStore
         // TODO decide on Map name scheme to avoid collision
         // TODO decide on Map name scheme to avoid collision
         rawLinks = theInstance.getMap("links");
         rawLinks = theInstance.getMap("links");
         final OptionalCacheLoader<LinkKey, DefaultLink> linkLoader
         final OptionalCacheLoader<LinkKey, DefaultLink> linkLoader
-                = new OptionalCacheLoader<>(storeService, rawLinks);
+                = new OptionalCacheLoader<>(kryoSerializationService, rawLinks);
         links = new AbsentInvalidatingLoadingCache<>(newBuilder().build(linkLoader));
         links = new AbsentInvalidatingLoadingCache<>(newBuilder().build(linkLoader));
         // refresh/populate cache based on notification from other instance
         // refresh/populate cache based on notification from other instance
-        rawLinks.addEntryListener(new RemoteLinkEventHandler(links), includeValue);
+        linksListener = rawLinks.addEntryListener(new RemoteLinkEventHandler(links), includeValue);
 
 
         loadLinkCache();
         loadLinkCache();
 
 
@@ -80,7 +82,7 @@ public class DistributedLinkStore
 
 
     @Deactivate
     @Deactivate
     public void deactivate() {
     public void deactivate() {
-        super.activate();
+        rawLinks.removeEntryListener(linksListener);
         log.info("Stopped");
         log.info("Stopped");
     }
     }
 
 
@@ -233,7 +235,7 @@ public class DistributedLinkStore
         }
         }
     }
     }
 
 
-    private class RemoteLinkEventHandler extends RemoteEventHandler<LinkKey, DefaultLink> {
+    private class RemoteLinkEventHandler extends RemoteCacheEventHandler<LinkKey, DefaultLink> {
         public RemoteLinkEventHandler(LoadingCache<LinkKey, Optional<DefaultLink>> cache) {
         public RemoteLinkEventHandler(LoadingCache<LinkKey, Optional<DefaultLink>> cache) {
             super(cache);
             super(cache);
         }
         }

@@ -20,6 +20,7 @@ import org.junit.After;
 import org.junit.AfterClass;
 import org.junit.AfterClass;
 import org.junit.Before;
 import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.BeforeClass;
+import org.junit.Ignore;
 import org.junit.Test;
 import org.junit.Test;
 import org.onlab.onos.net.Device;
 import org.onlab.onos.net.Device;
 import org.onlab.onos.net.DeviceId;
 import org.onlab.onos.net.DeviceId;
@@ -35,12 +36,17 @@ import org.onlab.onos.net.provider.ProviderId;
 import org.onlab.onos.store.common.StoreManager;
 import org.onlab.onos.store.common.StoreManager;
 import org.onlab.onos.store.common.StoreService;
 import org.onlab.onos.store.common.StoreService;
 import org.onlab.onos.store.common.TestStoreManager;
 import org.onlab.onos.store.common.TestStoreManager;
+import org.onlab.onos.store.serializers.KryoSerializationManager;
+import org.onlab.onos.store.serializers.KryoSerializationService;
 
 
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Sets;
 import com.google.common.collect.Sets;
 import com.hazelcast.config.Config;
 import com.hazelcast.config.Config;
 import com.hazelcast.core.Hazelcast;
 import com.hazelcast.core.Hazelcast;
 
 
+/**
+ * Test of the Hazelcast based distributed DeviceStore implementation.
+ */
 public class DistributedDeviceStoreTest {
 public class DistributedDeviceStoreTest {
 
 
     private static final ProviderId PID = new ProviderId("of", "foo");
     private static final ProviderId PID = new ProviderId("of", "foo");
@@ -57,6 +63,7 @@ public class DistributedDeviceStoreTest {
     private static final PortNumber P3 = PortNumber.portNumber(3);
     private static final PortNumber P3 = PortNumber.portNumber(3);
 
 
     private DistributedDeviceStore deviceStore;
     private DistributedDeviceStore deviceStore;
+    private KryoSerializationManager serializationMgr;
 
 
     private StoreManager storeManager;
     private StoreManager storeManager;
 
 
@@ -78,7 +85,10 @@ public class DistributedDeviceStoreTest {
         storeManager = new TestStoreManager(Hazelcast.newHazelcastInstance(config));
         storeManager = new TestStoreManager(Hazelcast.newHazelcastInstance(config));
         storeManager.activate();
         storeManager.activate();
 
 
-        deviceStore = new TestDistributedDeviceStore(storeManager);
+        serializationMgr = new KryoSerializationManager();
+        serializationMgr.activate();
+
+        deviceStore = new TestDistributedDeviceStore(storeManager, serializationMgr);
         deviceStore.activate();
         deviceStore.activate();
     }
     }
 
 
@@ -86,6 +96,8 @@ public class DistributedDeviceStoreTest {
     public void tearDown() throws Exception {
     public void tearDown() throws Exception {
         deviceStore.deactivate();
         deviceStore.deactivate();
 
 
+        serializationMgr.deactivate();
+
         storeManager.deactivate();
         storeManager.deactivate();
     }
     }
 
 
@@ -326,6 +338,7 @@ public class DistributedDeviceStoreTest {
     }
     }
 
 
     // TODO add test for Port events when we have them
     // TODO add test for Port events when we have them
+    @Ignore("Ignore until Delegate spec. is clear.")
     @Test
     @Test
     public final void testEvents() throws InterruptedException {
     public final void testEvents() throws InterruptedException {
         final CountDownLatch addLatch = new CountDownLatch(1);
         final CountDownLatch addLatch = new CountDownLatch(1);
@@ -379,8 +392,10 @@ public class DistributedDeviceStoreTest {
     }
     }
 
 
     private class TestDistributedDeviceStore extends DistributedDeviceStore {
     private class TestDistributedDeviceStore extends DistributedDeviceStore {
-        public TestDistributedDeviceStore(StoreService storeService) {
+        public TestDistributedDeviceStore(StoreService storeService,
+                                KryoSerializationService kryoSerializationService) {
             this.storeService = storeService;
             this.storeService = storeService;
+            this.kryoSerializationService = kryoSerializationService;
         }
         }
     }
     }
 }
 }

@@ -15,6 +15,7 @@ import org.junit.After;
 import org.junit.AfterClass;
 import org.junit.AfterClass;
 import org.junit.Before;
 import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.BeforeClass;
+import org.junit.Ignore;
 import org.junit.Test;
 import org.junit.Test;
 import org.onlab.onos.net.ConnectPoint;
 import org.onlab.onos.net.ConnectPoint;
 import org.onlab.onos.net.DeviceId;
 import org.onlab.onos.net.DeviceId;
@@ -29,27 +30,28 @@ import org.onlab.onos.net.provider.ProviderId;
 import org.onlab.onos.store.common.StoreManager;
 import org.onlab.onos.store.common.StoreManager;
 import org.onlab.onos.store.common.StoreService;
 import org.onlab.onos.store.common.StoreService;
 import org.onlab.onos.store.common.TestStoreManager;
 import org.onlab.onos.store.common.TestStoreManager;
+import org.onlab.onos.store.serializers.KryoSerializationManager;
+import org.onlab.onos.store.serializers.KryoSerializationService;
 
 
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Iterables;
 import com.hazelcast.config.Config;
 import com.hazelcast.config.Config;
 import com.hazelcast.core.Hazelcast;
 import com.hazelcast.core.Hazelcast;
 
 
+/**
+ * Test of the Hazelcast based distributed LinkStore implementation.
+ */
 public class DistributedLinkStoreTest {
 public class DistributedLinkStoreTest {
 
 
     private static final ProviderId PID = new ProviderId("of", "foo");
     private static final ProviderId PID = new ProviderId("of", "foo");
     private static final DeviceId DID1 = deviceId("of:foo");
     private static final DeviceId DID1 = deviceId("of:foo");
     private static final DeviceId DID2 = deviceId("of:bar");
     private static final DeviceId DID2 = deviceId("of:bar");
-//    private static final String MFR = "whitebox";
-//    private static final String HW = "1.1.x";
-//    private static final String SW1 = "3.8.1";
-//    private static final String SW2 = "3.9.5";
-//    private static final String SN = "43311-12345";
 
 
     private static final PortNumber P1 = PortNumber.portNumber(1);
     private static final PortNumber P1 = PortNumber.portNumber(1);
     private static final PortNumber P2 = PortNumber.portNumber(2);
     private static final PortNumber P2 = PortNumber.portNumber(2);
     private static final PortNumber P3 = PortNumber.portNumber(3);
     private static final PortNumber P3 = PortNumber.portNumber(3);
 
 
     private StoreManager storeManager;
     private StoreManager storeManager;
+    private KryoSerializationManager serializationMgr;
 
 
     private DistributedLinkStore linkStore;
     private DistributedLinkStore linkStore;
 
 
@@ -69,13 +71,17 @@ public class DistributedLinkStoreTest {
         storeManager = new TestStoreManager(Hazelcast.newHazelcastInstance(config));
         storeManager = new TestStoreManager(Hazelcast.newHazelcastInstance(config));
         storeManager.activate();
         storeManager.activate();
 
 
-        linkStore = new TestDistributedLinkStore(storeManager);
+        serializationMgr = new KryoSerializationManager();
+        serializationMgr.activate();
+
+        linkStore = new TestDistributedLinkStore(storeManager, serializationMgr);
         linkStore.activate();
         linkStore.activate();
     }
     }
 
 
     @After
     @After
     public void tearDown() throws Exception {
     public void tearDown() throws Exception {
         linkStore.deactivate();
         linkStore.deactivate();
+        serializationMgr.deactivate();
         storeManager.deactivate();
         storeManager.deactivate();
     }
     }
 
 
@@ -302,6 +308,7 @@ public class DistributedLinkStoreTest {
         assertLink(linkId2, DIRECT, linkStore.getLink(d2P2, d1P1));
         assertLink(linkId2, DIRECT, linkStore.getLink(d2P2, d1P1));
     }
     }
 
 
+    @Ignore("Ignore until Delegate spec. is clear.")
     @Test
     @Test
     public final void testEvents() throws InterruptedException {
     public final void testEvents() throws InterruptedException {
 
 
@@ -354,8 +361,10 @@ public class DistributedLinkStoreTest {
 
 
 
 
     class TestDistributedLinkStore extends DistributedLinkStore {
     class TestDistributedLinkStore extends DistributedLinkStore {
-        TestDistributedLinkStore(StoreService storeService) {
+        TestDistributedLinkStore(StoreService storeService,
+                            KryoSerializationService kryoSerializationService) {
             this.storeService = storeService;
             this.storeService = storeService;
+            this.kryoSerializationService = kryoSerializationService;
         }
         }
     }
     }
 }
 }

+package org.onlab.onos.store.serializers;
+
+import java.net.URI;
+import java.util.ArrayList;
+import java.util.HashMap;
+
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Service;
+import org.onlab.onos.cluster.ControllerNode;
+import org.onlab.onos.cluster.DefaultControllerNode;
+import org.onlab.onos.cluster.NodeId;
+import org.onlab.onos.net.ConnectPoint;
+import org.onlab.onos.net.DefaultDevice;
+import org.onlab.onos.net.DefaultLink;
+import org.onlab.onos.net.DefaultPort;
+import org.onlab.onos.net.Device;
+import org.onlab.onos.net.DeviceId;
+import org.onlab.onos.net.Element;
+import org.onlab.onos.net.Link;
+import org.onlab.onos.net.LinkKey;
+import org.onlab.onos.net.MastershipRole;
+import org.onlab.onos.net.Port;
+import org.onlab.onos.net.PortNumber;
+import org.onlab.onos.net.provider.ProviderId;
+import org.onlab.packet.IpPrefix;
+import org.onlab.util.KryoPool;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import de.javakaffee.kryoserializers.URISerializer;
+
+/**
+ * Serialization service using Kryo.
+ */
+@Component(immediate = true)
+@Service
+public class KryoSerializationManager implements KryoSerializationService {
+
+    private final Logger log = LoggerFactory.getLogger(getClass());
+    private KryoPool serializerPool;
+
+
+    @Activate
+    public void activate() {
+        setupKryoPool();
+        log.info("Started");
+    }
+
+    @Deactivate
+    public void deactivate() {
+        log.info("Stopped");
+    }
+
+    /**
+     * Sets up the common serialzers pool.
+     */
+    protected void setupKryoPool() {
+        // FIXME Slice out types used in common to separate pool/namespace.
+        serializerPool = KryoPool.newBuilder()
+                .register(ArrayList.class,
+                          HashMap.class,
+
+                          ControllerNode.State.class,
+                          Device.Type.class,
+
+                          DefaultControllerNode.class,
+                          DefaultDevice.class,
+                          MastershipRole.class,
+                          Port.class,
+                          Element.class,
+
+                          Link.Type.class
+                )
+                .register(IpPrefix.class, new IpPrefixSerializer())
+                .register(URI.class, new URISerializer())
+                .register(NodeId.class, new NodeIdSerializer())
+                .register(ProviderId.class, new ProviderIdSerializer())
+                .register(DeviceId.class, new DeviceIdSerializer())
+                .register(PortNumber.class, new PortNumberSerializer())
+                .register(DefaultPort.class, new DefaultPortSerializer())
+                .register(LinkKey.class, new LinkKeySerializer())
+                .register(ConnectPoint.class, new ConnectPointSerializer())
+                .register(DefaultLink.class, new DefaultLinkSerializer())
+                .build()
+                .populate(1);
+    }
+
+    @Override
+    public byte[] serialize(final Object obj) {
+        return serializerPool.serialize(obj);
+    }
+
+    @Override
+    public <T> T deserialize(final byte[] bytes) {
+        if (bytes == null) {
+            return null;
+        }
+        return serializerPool.deserialize(bytes);
+    }
+
+}

+package org.onlab.onos.store.serializers;
+
+// TODO: To be replaced with SerializationService from IOLoop activity
+/**
+ * Service to serialize Objects into byte array.
+ */
+public interface KryoSerializationService {
+
+    /**
+     * Serializes the specified object into bytes using one of the
+     * pre-registered serializers.
+     *
+     * @param obj object to be serialized
+     * @return serialized bytes
+     */
+    public byte[] serialize(final Object obj);
+
+    /**
+     * Deserializes the specified bytes into an object using one of the
+     * pre-registered serializers.
+     *
+     * @param bytes bytes to be deserialized
+     * @return deserialized object
+     */
+    public <T> T deserialize(final byte[] bytes);
+
+}

@@ -20,7 +20,7 @@ import java.util.Set;
 import static org.slf4j.LoggerFactory.getLogger;
 import static org.slf4j.LoggerFactory.getLogger;
 
 
 /**
 /**
- * Manages inventory of infrastructure DEVICES using trivial in-memory
+ * Manages inventory of infrastructure devices using trivial in-memory
  * structures implementation.
  * structures implementation.
  */
  */
 @Component(immediate = true)
 @Component(immediate = true)
@@ -68,6 +68,11 @@ public class SimpleClusterStore
     }
     }
 
 
     @Override
     @Override
+    public ControllerNode addNode(NodeId nodeId, IpPrefix ip, int tcpPort) {
+        return null;
+    }
+
+    @Override
     public void removeNode(NodeId nodeId) {
     public void removeNode(NodeId nodeId) {
     }
     }
 
 

@@ -101,9 +101,6 @@ public class SimpleDeviceStore
         synchronized (this) {
         synchronized (this) {
             devices.put(deviceId, device);
             devices.put(deviceId, device);
             availableDevices.add(deviceId);
             availableDevices.add(deviceId);
-
-            // For now claim the device as a master automatically.
-            // roles.put(deviceId, MastershipRole.MASTER);
         }
         }
         return new DeviceEvent(DeviceEvent.Type.DEVICE_ADDED, device, null);
         return new DeviceEvent(DeviceEvent.Type.DEVICE_ADDED, device, null);
     }
     }
@@ -189,7 +186,7 @@ public class SimpleDeviceStore
                     new DefaultPort(device, portDescription.portNumber(),
                     new DefaultPort(device, portDescription.portNumber(),
                                     portDescription.isEnabled());
                                     portDescription.isEnabled());
             ports.put(port.number(), updatedPort);
             ports.put(port.number(), updatedPort);
-            return new DeviceEvent(PORT_UPDATED, device, port);
+            return new DeviceEvent(PORT_UPDATED, device, updatedPort);
         }
         }
         return null;
         return null;
     }
     }

@@ -51,8 +51,6 @@ public class SimpleLinkStore
     private final Multimap<DeviceId, Link> srcLinks = HashMultimap.create();
     private final Multimap<DeviceId, Link> srcLinks = HashMultimap.create();
     private final Multimap<DeviceId, Link> dstLinks = HashMultimap.create();
     private final Multimap<DeviceId, Link> dstLinks = HashMultimap.create();
 
 
-    private static final Set<Link> EMPTY = ImmutableSet.of();
-
     @Activate
     @Activate
     public void activate() {
     public void activate() {
         log.info("Started");
         log.info("Started");

+/**
+ *
+ */
+package org.onlab.onos.net.trivial.impl;
+
+import static org.junit.Assert.*;
+import static org.onlab.onos.net.Device.Type.SWITCH;
+import static org.onlab.onos.net.DeviceId.deviceId;
+import static org.onlab.onos.net.device.DeviceEvent.Type.*;
+
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import org.junit.After;
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Ignore;
+import org.junit.Test;
+import org.onlab.onos.net.Device;
+import org.onlab.onos.net.DeviceId;
+import org.onlab.onos.net.Port;
+import org.onlab.onos.net.PortNumber;
+import org.onlab.onos.net.device.DefaultDeviceDescription;
+import org.onlab.onos.net.device.DefaultPortDescription;
+import org.onlab.onos.net.device.DeviceDescription;
+import org.onlab.onos.net.device.DeviceEvent;
+import org.onlab.onos.net.device.DeviceStore;
+import org.onlab.onos.net.device.DeviceStoreDelegate;
+import org.onlab.onos.net.device.PortDescription;
+import org.onlab.onos.net.provider.ProviderId;
+
+import com.google.common.collect.Iterables;
+import com.google.common.collect.Sets;
+
+/**
+ * Test of the simple DeviceStore implementation.
+ */
+public class SimpleDeviceStoreTest {
+
+    private static final ProviderId PID = new ProviderId("of", "foo");
+    private static final DeviceId DID1 = deviceId("of:foo");
+    private static final DeviceId DID2 = deviceId("of:bar");
+    private static final String MFR = "whitebox";
+    private static final String HW = "1.1.x";
+    private static final String SW1 = "3.8.1";
+    private static final String SW2 = "3.9.5";
+    private static final String SN = "43311-12345";
+
+    private static final PortNumber P1 = PortNumber.portNumber(1);
+    private static final PortNumber P2 = PortNumber.portNumber(2);
+    private static final PortNumber P3 = PortNumber.portNumber(3);
+
+    private SimpleDeviceStore simpleDeviceStore;
+    private DeviceStore deviceStore;
+
+
+
+    @BeforeClass
+    public static void setUpBeforeClass() throws Exception {
+    }
+
+    @AfterClass
+    public static void tearDownAfterClass() throws Exception {
+    }
+
+
+    @Before
+    public void setUp() throws Exception {
+        simpleDeviceStore = new SimpleDeviceStore();
+        simpleDeviceStore.activate();
+        deviceStore = simpleDeviceStore;
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        simpleDeviceStore.deactivate();
+    }
+
+    private void putDevice(DeviceId deviceId, String swVersion) {
+        DeviceDescription description =
+                new DefaultDeviceDescription(deviceId.uri(), SWITCH, MFR,
+                        HW, swVersion, SN);
+        deviceStore.createOrUpdateDevice(PID, deviceId, description);
+    }
+
+    private static void assertDevice(DeviceId id, String swVersion, Device device) {
+        assertNotNull(device);
+        assertEquals(id, device.id());
+        assertEquals(MFR, device.manufacturer());
+        assertEquals(HW, device.hwVersion());
+        assertEquals(swVersion, device.swVersion());
+        assertEquals(SN, device.serialNumber());
+    }
+
+    @Test
+    public final void testGetDeviceCount() {
+        assertEquals("initialy empty", 0, deviceStore.getDeviceCount());
+
+        putDevice(DID1, SW1);
+        putDevice(DID2, SW2);
+        putDevice(DID1, SW1);
+
+        assertEquals("expect 2 uniq devices", 2, deviceStore.getDeviceCount());
+    }
+
+    @Test
+    public final void testGetDevices() {
+        assertEquals("initialy empty", 0, Iterables.size(deviceStore.getDevices()));
+
+        putDevice(DID1, SW1);
+        putDevice(DID2, SW2);
+        putDevice(DID1, SW1);
+
+        assertEquals("expect 2 uniq devices",
+                2, Iterables.size(deviceStore.getDevices()));
+
+        Map<DeviceId, Device> devices = new HashMap<>();
+        for (Device device : deviceStore.getDevices()) {
+            devices.put(device.id(), device);
+        }
+
+        assertDevice(DID1, SW1, devices.get(DID1));
+        assertDevice(DID2, SW2, devices.get(DID2));
+
+        // add case for new node?
+    }
+
+    @Test
+    public final void testGetDevice() {
+
+        putDevice(DID1, SW1);
+
+        assertDevice(DID1, SW1, deviceStore.getDevice(DID1));
+        assertNull("DID2 shouldn't be there", deviceStore.getDevice(DID2));
+    }
+
+    @Test
+    public final void testCreateOrUpdateDevice() {
+        DeviceDescription description =
+                new DefaultDeviceDescription(DID1.uri(), SWITCH, MFR,
+                        HW, SW1, SN);
+        DeviceEvent event = deviceStore.createOrUpdateDevice(PID, DID1, description);
+        assertEquals(DEVICE_ADDED, event.type());
+        assertDevice(DID1, SW1, event.subject());
+
+        DeviceDescription description2 =
+                new DefaultDeviceDescription(DID1.uri(), SWITCH, MFR,
+                        HW, SW2, SN);
+        DeviceEvent event2 = deviceStore.createOrUpdateDevice(PID, DID1, description2);
+        assertEquals(DEVICE_UPDATED, event2.type());
+        assertDevice(DID1, SW2, event2.subject());
+
+        assertNull("No change expected", deviceStore.createOrUpdateDevice(PID, DID1, description2));
+    }
+
+    @Test
+    public final void testMarkOffline() {
+
+        putDevice(DID1, SW1);
+        assertTrue(deviceStore.isAvailable(DID1));
+
+        DeviceEvent event = deviceStore.markOffline(DID1);
+        assertEquals(DEVICE_AVAILABILITY_CHANGED, event.type());
+        assertDevice(DID1, SW1, event.subject());
+        assertFalse(deviceStore.isAvailable(DID1));
+
+        DeviceEvent event2 = deviceStore.markOffline(DID1);
+        assertNull("No change, no event", event2);
+}
+
+    @Test
+    public final void testUpdatePorts() {
+        putDevice(DID1, SW1);
+        List<PortDescription> pds = Arrays.<PortDescription>asList(
+                new DefaultPortDescription(P1, true),
+                new DefaultPortDescription(P2, true)
+                );
+
+        List<DeviceEvent> events = deviceStore.updatePorts(DID1, pds);
+
+        Set<PortNumber> expectedPorts = Sets.newHashSet(P1, P2);
+        for (DeviceEvent event : events) {
+            assertEquals(PORT_ADDED, event.type());
+            assertDevice(DID1, SW1, event.subject());
+            assertTrue("PortNumber is one of expected",
+                    expectedPorts.remove(event.port().number()));
+            assertTrue("Port is enabled", event.port().isEnabled());
+        }
+        assertTrue("Event for all expectedport appeared", expectedPorts.isEmpty());
+
+
+        List<PortDescription> pds2 = Arrays.<PortDescription>asList(
+                new DefaultPortDescription(P1, false),
+                new DefaultPortDescription(P2, true),
+                new DefaultPortDescription(P3, true)
+                );
+
+        events = deviceStore.updatePorts(DID1, pds2);
+        assertFalse("event should be triggered", events.isEmpty());
+        for (DeviceEvent event : events) {
+            PortNumber num = event.port().number();
+            if (P1.equals(num)) {
+                assertEquals(PORT_UPDATED, event.type());
+                assertDevice(DID1, SW1, event.subject());
+                assertFalse("Port is disabled", event.port().isEnabled());
+            } else if (P2.equals(num)) {
+                fail("P2 event not expected.");
+            } else if (P3.equals(num)) {
+                assertEquals(PORT_ADDED, event.type());
+                assertDevice(DID1, SW1, event.subject());
+                assertTrue("Port is enabled", event.port().isEnabled());
+            } else {
+                fail("Unknown port number encountered: " + num);
+            }
+        }
+
+        List<PortDescription> pds3 = Arrays.<PortDescription>asList(
+                new DefaultPortDescription(P1, false),
+                new DefaultPortDescription(P2, true)
+                );
+        events = deviceStore.updatePorts(DID1, pds3);
+        assertFalse("event should be triggered", events.isEmpty());
+        for (DeviceEvent event : events) {
+            PortNumber num = event.port().number();
+            if (P1.equals(num)) {
+                fail("P1 event not expected.");
+            } else if (P2.equals(num)) {
+                fail("P2 event not expected.");
+            } else if (P3.equals(num)) {
+                assertEquals(PORT_REMOVED, event.type());
+                assertDevice(DID1, SW1, event.subject());
+                assertTrue("Port was enabled", event.port().isEnabled());
+            } else {
+                fail("Unknown port number encountered: " + num);
+            }
+        }
+
+    }
+
+    @Test
+    public final void testUpdatePortStatus() {
+        putDevice(DID1, SW1);
+        List<PortDescription> pds = Arrays.<PortDescription>asList(
+                new DefaultPortDescription(P1, true)
+                );
+        deviceStore.updatePorts(DID1, pds);
+
+        DeviceEvent event = deviceStore.updatePortStatus(DID1,
+                new DefaultPortDescription(P1, false));
+        assertEquals(PORT_UPDATED, event.type());
+        assertDevice(DID1, SW1, event.subject());
+        assertEquals(P1, event.port().number());
+        assertFalse("Port is disabled", event.port().isEnabled());
+    }
+
+    @Test
+    public final void testGetPorts() {
+        putDevice(DID1, SW1);
+        putDevice(DID2, SW1);
+        List<PortDescription> pds = Arrays.<PortDescription>asList(
+                new DefaultPortDescription(P1, true),
+                new DefaultPortDescription(P2, true)
+                );
+        deviceStore.updatePorts(DID1, pds);
+
+        Set<PortNumber> expectedPorts = Sets.newHashSet(P1, P2);
+        List<Port> ports = deviceStore.getPorts(DID1);
+        for (Port port : ports) {
+            assertTrue("Port is enabled", port.isEnabled());
+            assertTrue("PortNumber is one of expected",
+                    expectedPorts.remove(port.number()));
+        }
+        assertTrue("Event for all expectedport appeared", expectedPorts.isEmpty());
+
+
+        assertTrue("DID2 has no ports", deviceStore.getPorts(DID2).isEmpty());
+    }
+
+    @Test
+    public final void testGetPort() {
+        putDevice(DID1, SW1);
+        putDevice(DID2, SW1);
+        List<PortDescription> pds = Arrays.<PortDescription>asList(
+                new DefaultPortDescription(P1, true),
+                new DefaultPortDescription(P2, false)
+                );
+        deviceStore.updatePorts(DID1, pds);
+
+        Port port1 = deviceStore.getPort(DID1, P1);
+        assertEquals(P1, port1.number());
+        assertTrue("Port is enabled", port1.isEnabled());
+
+        Port port2 = deviceStore.getPort(DID1, P2);
+        assertEquals(P2, port2.number());
+        assertFalse("Port is disabled", port2.isEnabled());
+
+        Port port3 = deviceStore.getPort(DID1, P3);
+        assertNull("P3 not expected", port3);
+    }
+
+    @Test
+    public final void testRemoveDevice() {
+        putDevice(DID1, SW1);
+        putDevice(DID2, SW1);
+
+        assertEquals(2, deviceStore.getDeviceCount());
+
+        DeviceEvent event = deviceStore.removeDevice(DID1);
+        assertEquals(DEVICE_REMOVED, event.type());
+        assertDevice(DID1, SW1, event.subject());
+
+        assertEquals(1, deviceStore.getDeviceCount());
+    }
+
+    // If Delegates should be called only on remote events,
+    // then Simple* should never call them, thus not test required.
+    // TODO add test for Port events when we have them
+    @Ignore("Ignore until Delegate spec. is clear.")
+    @Test
+    public final void testEvents() throws InterruptedException {
+        final CountDownLatch addLatch = new CountDownLatch(1);
+        DeviceStoreDelegate checkAdd = new DeviceStoreDelegate() {
+            @Override
+            public void notify(DeviceEvent event) {
+                assertEquals(DEVICE_ADDED, event.type());
+                assertDevice(DID1, SW1, event.subject());
+                addLatch.countDown();
+            }
+        };
+        final CountDownLatch updateLatch = new CountDownLatch(1);
+        DeviceStoreDelegate checkUpdate = new DeviceStoreDelegate() {
+            @Override
+            public void notify(DeviceEvent event) {
+                assertEquals(DEVICE_UPDATED, event.type());
+                assertDevice(DID1, SW2, event.subject());
+                updateLatch.countDown();
+            }
+        };
+        final CountDownLatch removeLatch = new CountDownLatch(1);
+        DeviceStoreDelegate checkRemove = new DeviceStoreDelegate() {
+            @Override
+            public void notify(DeviceEvent event) {
+                assertEquals(DEVICE_REMOVED, event.type());
+                assertDevice(DID1, SW2, event.subject());
+                removeLatch.countDown();
+            }
+        };
+
+        DeviceDescription description =
+                new DefaultDeviceDescription(DID1.uri(), SWITCH, MFR,
+                        HW, SW1, SN);
+        deviceStore.setDelegate(checkAdd);
+        deviceStore.createOrUpdateDevice(PID, DID1, description);
+        assertTrue("Add event fired", addLatch.await(1, TimeUnit.SECONDS));
+
+
+        DeviceDescription description2 =
+                new DefaultDeviceDescription(DID1.uri(), SWITCH, MFR,
+                        HW, SW2, SN);
+        deviceStore.unsetDelegate(checkAdd);
+        deviceStore.setDelegate(checkUpdate);
+        deviceStore.createOrUpdateDevice(PID, DID1, description2);
+        assertTrue("Update event fired", updateLatch.await(1, TimeUnit.SECONDS));
+
+        deviceStore.unsetDelegate(checkUpdate);
+        deviceStore.setDelegate(checkRemove);
+        deviceStore.removeDevice(DID1);
+        assertTrue("Remove event fired", removeLatch.await(1, TimeUnit.SECONDS));
+    }
+}

+package org.onlab.onos.net.trivial.impl;
+
+import static org.junit.Assert.*;
+import static org.onlab.onos.net.DeviceId.deviceId;
+import static org.onlab.onos.net.Link.Type.*;
+import static org.onlab.onos.net.link.LinkEvent.Type.*;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import org.junit.After;
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Ignore;
+import org.junit.Test;
+import org.onlab.onos.net.ConnectPoint;
+import org.onlab.onos.net.DeviceId;
+import org.onlab.onos.net.Link;
+import org.onlab.onos.net.LinkKey;
+import org.onlab.onos.net.PortNumber;
+import org.onlab.onos.net.Link.Type;
+import org.onlab.onos.net.link.DefaultLinkDescription;
+import org.onlab.onos.net.link.LinkEvent;
+import org.onlab.onos.net.link.LinkStore;
+import org.onlab.onos.net.link.LinkStoreDelegate;
+import org.onlab.onos.net.provider.ProviderId;
+
+import com.google.common.collect.Iterables;
+
+/**
+ * Test of the simple LinkStore implementation.
+ */
+public class SimpleLinkStoreTest {
+
+    private static final ProviderId PID = new ProviderId("of", "foo");
+    private static final DeviceId DID1 = deviceId("of:foo");
+    private static final DeviceId DID2 = deviceId("of:bar");
+
+    private static final PortNumber P1 = PortNumber.portNumber(1);
+    private static final PortNumber P2 = PortNumber.portNumber(2);
+    private static final PortNumber P3 = PortNumber.portNumber(3);
+
+
+    private SimpleLinkStore simpleLinkStore;
+    private LinkStore linkStore;
+
+    @BeforeClass
+    public static void setUpBeforeClass() throws Exception {
+    }
+
+    @AfterClass
+    public static void tearDownAfterClass() throws Exception {
+    }
+
+    @Before
+    public void setUp() throws Exception {
+        simpleLinkStore = new SimpleLinkStore();
+        simpleLinkStore.activate();
+        linkStore = simpleLinkStore;
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        simpleLinkStore.deactivate();
+    }
+
+    private void putLink(DeviceId srcId, PortNumber srcNum,
+                         DeviceId dstId, PortNumber dstNum, Type type) {
+        ConnectPoint src = new ConnectPoint(srcId, srcNum);
+        ConnectPoint dst = new ConnectPoint(dstId, dstNum);
+        linkStore.createOrUpdateLink(PID, new DefaultLinkDescription(src, dst, type));
+    }
+
+    private void putLink(LinkKey key, Type type) {
+        putLink(key.src().deviceId(), key.src().port(),
+                key.dst().deviceId(), key.dst().port(),
+                type);
+    }
+
+    private static void assertLink(DeviceId srcId, PortNumber srcNum,
+                            DeviceId dstId, PortNumber dstNum, Type type,
+                            Link link) {
+        assertEquals(srcId, link.src().deviceId());
+        assertEquals(srcNum, link.src().port());
+        assertEquals(dstId, link.dst().deviceId());
+        assertEquals(dstNum, link.dst().port());
+        assertEquals(type, link.type());
+    }
+
+    private static void assertLink(LinkKey key, Type type, Link link) {
+        assertLink(key.src().deviceId(), key.src().port(),
+                   key.dst().deviceId(), key.dst().port(),
+                   type, link);
+    }
+
+    @Test
+    public final void testGetLinkCount() {
+        assertEquals("initialy empty", 0, linkStore.getLinkCount());
+
+        putLink(DID1, P1, DID2, P2, DIRECT);
+        putLink(DID2, P2, DID1, P1, DIRECT);
+        putLink(DID1, P1, DID2, P2, DIRECT);
+
+        assertEquals("expecting 2 unique link", 2, linkStore.getLinkCount());
+    }
+
+    @Test
+    public final void testGetLinks() {
+        assertEquals("initialy empty", 0,
+                Iterables.size(linkStore.getLinks()));
+
+        LinkKey linkId1 = new LinkKey(new ConnectPoint(DID1, P1), new ConnectPoint(DID2, P2));
+        LinkKey linkId2 = new LinkKey(new ConnectPoint(DID2, P2), new ConnectPoint(DID1, P1));
+
+        putLink(linkId1, DIRECT);
+        putLink(linkId2, DIRECT);
+        putLink(linkId1, DIRECT);
+
+        assertEquals("expecting 2 unique link", 2,
+                Iterables.size(linkStore.getLinks()));
+
+        Map<LinkKey, Link> links = new HashMap<>();
+        for (Link link : linkStore.getLinks()) {
+            links.put(new LinkKey(link.src(), link.dst()), link);
+        }
+
+        assertLink(linkId1, DIRECT, links.get(linkId1));
+        assertLink(linkId2, DIRECT, links.get(linkId2));
+    }
+
+    @Test
+    public final void testGetDeviceEgressLinks() {
+        LinkKey linkId1 = new LinkKey(new ConnectPoint(DID1, P1), new ConnectPoint(DID2, P2));
+        LinkKey linkId2 = new LinkKey(new ConnectPoint(DID2, P2), new ConnectPoint(DID1, P1));
+        LinkKey linkId3 = new LinkKey(new ConnectPoint(DID1, P2), new ConnectPoint(DID2, P3));
+
+        putLink(linkId1, DIRECT);
+        putLink(linkId2, DIRECT);
+        putLink(linkId3, DIRECT);
+
+        // DID1,P1 => DID2,P2
+        // DID2,P2 => DID1,P1
+        // DID1,P2 => DID2,P3
+
+        Set<Link> links1 = linkStore.getDeviceEgressLinks(DID1);
+        assertEquals(2, links1.size());
+        // check
+
+        Set<Link> links2 = linkStore.getDeviceEgressLinks(DID2);
+        assertEquals(1, links2.size());
+        assertLink(linkId2, DIRECT, links2.iterator().next());
+    }
+
+    @Test
+    public final void testGetDeviceIngressLinks() {
+        LinkKey linkId1 = new LinkKey(new ConnectPoint(DID1, P1), new ConnectPoint(DID2, P2));
+        LinkKey linkId2 = new LinkKey(new ConnectPoint(DID2, P2), new ConnectPoint(DID1, P1));
+        LinkKey linkId3 = new LinkKey(new ConnectPoint(DID1, P2), new ConnectPoint(DID2, P3));
+
+        putLink(linkId1, DIRECT);
+        putLink(linkId2, DIRECT);
+        putLink(linkId3, DIRECT);
+
+        // DID1,P1 => DID2,P2
+        // DID2,P2 => DID1,P1
+        // DID1,P2 => DID2,P3
+
+        Set<Link> links1 = linkStore.getDeviceIngressLinks(DID2);
+        assertEquals(2, links1.size());
+        // check
+
+        Set<Link> links2 = linkStore.getDeviceIngressLinks(DID1);
+        assertEquals(1, links2.size());
+        assertLink(linkId2, DIRECT, links2.iterator().next());
+    }
+
+    @Test
+    public final void testGetLink() {
+        ConnectPoint src = new ConnectPoint(DID1, P1);
+        ConnectPoint dst = new ConnectPoint(DID2, P2);
+        LinkKey linkId1 = new LinkKey(src, dst);
+
+        putLink(linkId1, DIRECT);
+
+        Link link = linkStore.getLink(src, dst);
+        assertLink(linkId1, DIRECT, link);
+
+        assertNull("There shouldn't be reverese link",
+                linkStore.getLink(dst, src));
+    }
+
+    @Test
+    public final void testGetEgressLinks() {
+        final ConnectPoint d1P1 = new ConnectPoint(DID1, P1);
+        final ConnectPoint d2P2 = new ConnectPoint(DID2, P2);
+        LinkKey linkId1 = new LinkKey(d1P1, d2P2);
+        LinkKey linkId2 = new LinkKey(d2P2, d1P1);
+        LinkKey linkId3 = new LinkKey(new ConnectPoint(DID1, P2), new ConnectPoint(DID2, P3));
+
+        putLink(linkId1, DIRECT);
+        putLink(linkId2, DIRECT);
+        putLink(linkId3, DIRECT);
+
+        // DID1,P1 => DID2,P2
+        // DID2,P2 => DID1,P1
+        // DID1,P2 => DID2,P3
+
+        Set<Link> links1 = linkStore.getEgressLinks(d1P1);
+        assertEquals(1, links1.size());
+        assertLink(linkId1, DIRECT, links1.iterator().next());
+
+        Set<Link> links2 = linkStore.getEgressLinks(d2P2);
+        assertEquals(1, links2.size());
+        assertLink(linkId2, DIRECT, links2.iterator().next());
+    }
+
+    @Test
+    public final void testGetIngressLinks() {
+        final ConnectPoint d1P1 = new ConnectPoint(DID1, P1);
+        final ConnectPoint d2P2 = new ConnectPoint(DID2, P2);
+        LinkKey linkId1 = new LinkKey(d1P1, d2P2);
+        LinkKey linkId2 = new LinkKey(d2P2, d1P1);
+        LinkKey linkId3 = new LinkKey(new ConnectPoint(DID1, P2), new ConnectPoint(DID2, P3));
+
+        putLink(linkId1, DIRECT);
+        putLink(linkId2, DIRECT);
+        putLink(linkId3, DIRECT);
+
+        // DID1,P1 => DID2,P2
+        // DID2,P2 => DID1,P1
+        // DID1,P2 => DID2,P3
+
+        Set<Link> links1 = linkStore.getIngressLinks(d2P2);
+        assertEquals(1, links1.size());
+        assertLink(linkId1, DIRECT, links1.iterator().next());
+
+        Set<Link> links2 = linkStore.getIngressLinks(d1P1);
+        assertEquals(1, links2.size());
+        assertLink(linkId2, DIRECT, links2.iterator().next());
+    }
+
+    @Test
+    public final void testCreateOrUpdateLink() {
+        ConnectPoint src = new ConnectPoint(DID1, P1);
+        ConnectPoint dst = new ConnectPoint(DID2, P2);
+
+        // add link
+        LinkEvent event = linkStore.createOrUpdateLink(PID,
+                    new DefaultLinkDescription(src, dst, INDIRECT));
+
+        assertLink(DID1, P1, DID2, P2, INDIRECT, event.subject());
+        assertEquals(LINK_ADDED, event.type());
+
+        // update link type
+        LinkEvent event2 = linkStore.createOrUpdateLink(PID,
+                new DefaultLinkDescription(src, dst, DIRECT));
+
+        assertLink(DID1, P1, DID2, P2, DIRECT, event2.subject());
+        assertEquals(LINK_UPDATED, event2.type());
+
+        // no change
+        LinkEvent event3 = linkStore.createOrUpdateLink(PID,
+                new DefaultLinkDescription(src, dst, DIRECT));
+
+        assertNull("No change event expected", event3);
+    }
+
+    @Test
+    public final void testRemoveLink() {
+        final ConnectPoint d1P1 = new ConnectPoint(DID1, P1);
+        final ConnectPoint d2P2 = new ConnectPoint(DID2, P2);
+        LinkKey linkId1 = new LinkKey(d1P1, d2P2);
+        LinkKey linkId2 = new LinkKey(d2P2, d1P1);
+
+        putLink(linkId1, DIRECT);
+        putLink(linkId2, DIRECT);
+
+        // DID1,P1 => DID2,P2
+        // DID2,P2 => DID1,P1
+        // DID1,P2 => DID2,P3
+
+        LinkEvent event = linkStore.removeLink(d1P1, d2P2);
+        assertEquals(LINK_REMOVED, event.type());
+        LinkEvent event2 = linkStore.removeLink(d1P1, d2P2);
+        assertNull(event2);
+
+        assertLink(linkId2, DIRECT, linkStore.getLink(d2P2, d1P1));
+    }
+
+    // If Delegates should be called only on remote events,
+    // then Simple* should never call them, thus not test required.
+    @Ignore("Ignore until Delegate spec. is clear.")
+    @Test
+    public final void testEvents() throws InterruptedException {
+
+        final ConnectPoint d1P1 = new ConnectPoint(DID1, P1);
+        final ConnectPoint d2P2 = new ConnectPoint(DID2, P2);
+        final LinkKey linkId1 = new LinkKey(d1P1, d2P2);
+
+        final CountDownLatch addLatch = new CountDownLatch(1);
+        LinkStoreDelegate checkAdd = new LinkStoreDelegate() {
+            @Override
+            public void notify(LinkEvent event) {
+                assertEquals(LINK_ADDED, event.type());
+                assertLink(linkId1, INDIRECT, event.subject());
+                addLatch.countDown();
+            }
+        };
+        final CountDownLatch updateLatch = new CountDownLatch(1);
+        LinkStoreDelegate checkUpdate = new LinkStoreDelegate() {
+            @Override
+            public void notify(LinkEvent event) {
+                assertEquals(LINK_UPDATED, event.type());
+                assertLink(linkId1, DIRECT, event.subject());
+                updateLatch.countDown();
+            }
+        };
+        final CountDownLatch removeLatch = new CountDownLatch(1);
+        LinkStoreDelegate checkRemove = new LinkStoreDelegate() {
+            @Override
+            public void notify(LinkEvent event) {
+                assertEquals(LINK_REMOVED, event.type());
+                assertLink(linkId1, DIRECT, event.subject());
+                removeLatch.countDown();
+            }
+        };
+
+        linkStore.setDelegate(checkAdd);
+        putLink(linkId1, INDIRECT);
+        assertTrue("Add event fired", addLatch.await(1, TimeUnit.SECONDS));
+
+        linkStore.unsetDelegate(checkAdd);
+        linkStore.setDelegate(checkUpdate);
+        putLink(linkId1, DIRECT);
+        assertTrue("Update event fired", updateLatch.await(1, TimeUnit.SECONDS));
+
+        linkStore.unsetDelegate(checkUpdate);
+        linkStore.setDelegate(checkRemove);
+        linkStore.removeLink(d1P1, d2P2);
+        assertTrue("Remove event fired", removeLatch.await(1, TimeUnit.SECONDS));
+    }
+}

@@ -48,20 +48,17 @@
              description="ONOS core components">
              description="ONOS core components">
         <feature>onos-api</feature>
         <feature>onos-api</feature>
         <bundle>mvn:org.onlab.onos/onos-core-net/1.0.0-SNAPSHOT</bundle>
         <bundle>mvn:org.onlab.onos/onos-core-net/1.0.0-SNAPSHOT</bundle>
-        <bundle>mvn:org.onlab.onos/onos-core-hz-common/1.0.0-SNAPSHOT</bundle>
-        <bundle>mvn:org.onlab.onos/onos-core-serializers/1.0.0-SNAPSHOT</bundle>
-        <bundle>mvn:org.onlab.onos/onos-core-hz-cluster/1.0.0-SNAPSHOT</bundle>
-        <bundle>mvn:org.onlab.onos/onos-core-hz-net/1.0.0-SNAPSHOT</bundle>
+        <bundle>mvn:org.onlab.onos/onos-core-dist/1.0.0-SNAPSHOT</bundle>
     </feature>
     </feature>
 
 
-    <feature name="onos-core-dist" version="1.0.0"
-             description="ONOS core components">
+    <feature name="onos-core-hazelcast" version="1.0.0"
+             description="ONOS core components built on hazelcast">
         <feature>onos-api</feature>
         <feature>onos-api</feature>
         <bundle>mvn:org.onlab.onos/onos-core-net/1.0.0-SNAPSHOT</bundle>
         <bundle>mvn:org.onlab.onos/onos-core-net/1.0.0-SNAPSHOT</bundle>
         <bundle>mvn:org.onlab.onos/onos-core-hz-common/1.0.0-SNAPSHOT</bundle>
         <bundle>mvn:org.onlab.onos/onos-core-hz-common/1.0.0-SNAPSHOT</bundle>
         <bundle>mvn:org.onlab.onos/onos-core-serializers/1.0.0-SNAPSHOT</bundle>
         <bundle>mvn:org.onlab.onos/onos-core-serializers/1.0.0-SNAPSHOT</bundle>
         <bundle>mvn:org.onlab.onos/onos-core-hz-cluster/1.0.0-SNAPSHOT</bundle>
         <bundle>mvn:org.onlab.onos/onos-core-hz-cluster/1.0.0-SNAPSHOT</bundle>
-        <bundle>mvn:org.onlab.onos/onos-core-dist/1.0.0-SNAPSHOT</bundle>
+        <bundle>mvn:org.onlab.onos/onos-core-hz-net/1.0.0-SNAPSHOT</bundle>
     </feature>
     </feature>
 
 
     <feature name="onos-core-trivial" version="1.0.0"
     <feature name="onos-core-trivial" version="1.0.0"

@@ -9,5 +9,5 @@
 nodes=$(env | sort | egrep "OC[0-9]+" | cut -d= -f2)
 nodes=$(env | sort | egrep "OC[0-9]+" | cut -d= -f2)
 
 
 onos-package
 onos-package
-for node in $nodes; do printf "%s: " $node; onos-install -f $node; done
+for node in $nodes; do (printf "%s: %s\n" "$node" "`onos-install -f $node`")& done
 for node in $nodes; do onos-wait-for-start $node; done
 for node in $nodes; do onos-wait-for-start $node; done

@@ -15,7 +15,7 @@ env JAVA_HOME=/usr/lib/jvm/java-7-openjdk-amd64
 
 
 pre-stop script
 pre-stop script
     /opt/onos/bin/onos halt 2>/opt/onos/var/stderr.log
     /opt/onos/bin/onos halt 2>/opt/onos/var/stderr.log
-    sleep 3
+    sleep 2
 end script
 end script
 
 
 script
 script

@@ -8,7 +8,21 @@
 
 
 remote=$ONOS_USER@${1:-$OCI}
 remote=$ONOS_USER@${1:-$OCI}
 
 
+# Generate a cluster.json from the ON* environment variables
+CDEF_FILE=/tmp/cluster.json
+echo "{ \"nodes\":[" > $CDEF_FILE
+for node in $(env | sort | egrep "OC[2-9]+" | cut -d= -f2); do
+    echo "  { \"id\": \"$node\", \"ip\": \"$node\", \"tcpPort\": 9876 }," >> $CDEF_FILE
+done
+echo "  { \"id\": \"$OC1\", \"ip\": \"$OC1\", \"tcpPort\": 9876 }" >> $CDEF_FILE
+echo "]}" >> $CDEF_FILE
+
 ssh $remote "
 ssh $remote "
     sudo perl -pi.bak -e \"s/            <interface>.*</            <interface>${ONOS_NIC:-192.168.56.*}</g\" \
     sudo perl -pi.bak -e \"s/            <interface>.*</            <interface>${ONOS_NIC:-192.168.56.*}</g\" \
         $ONOS_INSTALL_DIR/$KARAF_DIST/etc/hazelcast.xml
         $ONOS_INSTALL_DIR/$KARAF_DIST/etc/hazelcast.xml
-"
\ No newline at end of file
+
+    echo \"onos.ip = \$(ifconfig | grep $ONOS_NIC | cut -d: -f2 | cut -d\\  -f1)\" \
+        >> $ONOS_INSTALL_DIR/$KARAF_DIST/etc/system.properties
+"
+
+scp -q $CDEF_FILE $remote:$ONOS_INSTALL_DIR/config/
\ No newline at end of file

@@ -24,6 +24,7 @@ ssh $remote "
     # Make a link to the log file directory and make a home for auxiliaries
     # Make a link to the log file directory and make a home for auxiliaries
     ln -s $ONOS_INSTALL_DIR/$KARAF_DIST/data/log /opt/onos/log
     ln -s $ONOS_INSTALL_DIR/$KARAF_DIST/data/log /opt/onos/log
     mkdir $ONOS_INSTALL_DIR/var
     mkdir $ONOS_INSTALL_DIR/var
+    mkdir $ONOS_INSTALL_DIR/config
 
 
     # Install the upstart configuration file and setup options for debugging
     # Install the upstart configuration file and setup options for debugging
     sudo cp $ONOS_INSTALL_DIR/debian/onos.conf /etc/init/onos.conf
     sudo cp $ONOS_INSTALL_DIR/debian/onos.conf /etc/init/onos.conf

 # Default virtual box ONOS instances 1,2 & ONOS mininet box
 # Default virtual box ONOS instances 1,2 & ONOS mininet box
 . $ONOS_ROOT/tools/test/cells/.reset
 . $ONOS_ROOT/tools/test/cells/.reset
 
 
+export ONOS_NIC=192.168.56.*
+
 export OC1="192.168.56.101"
 export OC1="192.168.56.101"
 export OC2="192.168.56.102"
 export OC2="192.168.56.102"
 
 

 package org.onlab.util;
 package org.onlab.util;
 
 
+import java.nio.ByteBuffer;
 import java.util.ArrayList;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.List;
 import java.util.concurrent.ConcurrentLinkedQueue;
 import java.util.concurrent.ConcurrentLinkedQueue;
@@ -8,6 +9,8 @@ import org.apache.commons.lang3.tuple.Pair;
 
 
 import com.esotericsoftware.kryo.Kryo;
 import com.esotericsoftware.kryo.Kryo;
 import com.esotericsoftware.kryo.Serializer;
 import com.esotericsoftware.kryo.Serializer;
+import com.esotericsoftware.kryo.io.ByteBufferInput;
+import com.esotericsoftware.kryo.io.ByteBufferOutput;
 import com.esotericsoftware.kryo.io.Input;
 import com.esotericsoftware.kryo.io.Input;
 import com.esotericsoftware.kryo.io.Output;
 import com.esotericsoftware.kryo.io.Output;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableList;
@@ -174,6 +177,22 @@ public final class KryoPool {
     }
     }
 
 
     /**
     /**
+     * Serializes given object to byte buffer using Kryo instance in pool.
+     *
+     * @param obj Object to serialize
+     * @param buffer to write to
+     */
+    public void serialize(final Object obj, final ByteBuffer buffer) {
+        ByteBufferOutput out = new ByteBufferOutput(buffer);
+        Kryo kryo = getKryo();
+        try {
+            kryo.writeClassAndObject(out, obj);
+        } finally {
+            putKryo(kryo);
+        }
+    }
+
+    /**
      * Deserializes given byte array to Object using Kryo instance in pool.
      * Deserializes given byte array to Object using Kryo instance in pool.
      *
      *
      * @param bytes serialized bytes
      * @param bytes serialized bytes
@@ -192,6 +211,24 @@ public final class KryoPool {
         }
         }
     }
     }
 
 
+    /**
+     * Deserializes given byte buffer to Object using Kryo instance in pool.
+     *
+     * @param buffer input with serialized bytes
+     * @param <T> deserialized Object type
+     * @return deserialized Object
+     */
+    public <T> T deserialize(final ByteBuffer buffer) {
+        ByteBufferInput in = new ByteBufferInput(buffer);
+        Kryo kryo = getKryo();
+        try {
+            @SuppressWarnings("unchecked")
+            T obj = (T) kryo.readClassAndObject(in);
+            return obj;
+        } finally {
+            putKryo(kryo);
+        }
+    }
 
 
     /**
     /**
      * Creates a Kryo instance with {@link #registeredTypes} pre-registered.
      * Creates a Kryo instance with {@link #registeredTypes} pre-registered.

@@ -54,6 +54,15 @@ public abstract class IOLoop<M extends Message, S extends MessageStream<M>>
     }
     }
 
 
     /**
     /**
+     * Returns the number of message stream in custody of the loop.
+     *
+     * @return number of message streams
+     */
+    public int streamCount() {
+        return streams.size();
+    }
+
+    /**
      * Creates a new message stream backed by the specified socket channel.
      * Creates a new message stream backed by the specified socket channel.
      *
      *
      * @param byteChannel backing byte channel
      * @param byteChannel backing byte channel
@@ -84,14 +93,9 @@ public abstract class IOLoop<M extends Message, S extends MessageStream<M>>
      *
      *
      * @param key selection key holding the pending connect operation.
      * @param key selection key holding the pending connect operation.
      */
      */
-    protected void connect(SelectionKey key) {
-        try {
-            SocketChannel ch = (SocketChannel) key.channel();
-            ch.finishConnect();
-        } catch (IOException | IllegalStateException e) {
-            log.warn("Unable to complete connection", e);
-        }
-
+    protected void connect(SelectionKey key) throws IOException {
+        SocketChannel ch = (SocketChannel) key.channel();
+        ch.finishConnect();
         if (key.isValid()) {
         if (key.isValid()) {
             key.interestOps(SelectionKey.OP_READ);
             key.interestOps(SelectionKey.OP_READ);
         }
         }
@@ -115,7 +119,11 @@ public abstract class IOLoop<M extends Message, S extends MessageStream<M>>
 
 
             // If there is a pending connect operation, complete it.
             // If there is a pending connect operation, complete it.
             if (key.isConnectable()) {
             if (key.isConnectable()) {
-                connect(key);
+                try {
+                    connect(key);
+                } catch (IOException | IllegalStateException e) {
+                    log.warn("Unable to complete connection", e);
+                }
             }
             }
 
 
             // If there is a read operation, slurp as much data as possible.
             // If there is a read operation, slurp as much data as possible.
@@ -182,9 +190,10 @@ public abstract class IOLoop<M extends Message, S extends MessageStream<M>>
      * with a pending accept operation.
      * with a pending accept operation.
      *
      *
      * @param channel backing socket channel
      * @param channel backing socket channel
+     * @return newly accepted message stream
      */
      */
-    public void acceptStream(SocketChannel channel) {
-        createAndAdmit(channel, SelectionKey.OP_READ);
+    public S acceptStream(SocketChannel channel) {
+        return createAndAdmit(channel, SelectionKey.OP_READ);
     }
     }
 
 
 
 
@@ -193,9 +202,10 @@ public abstract class IOLoop<M extends Message, S extends MessageStream<M>>
      * with a pending connect operation.
      * with a pending connect operation.
      *
      *
      * @param channel backing socket channel
      * @param channel backing socket channel
+     * @return newly connected message stream
      */
      */
-    public void connectStream(SocketChannel channel) {
-        createAndAdmit(channel, SelectionKey.OP_CONNECT);
+    public S connectStream(SocketChannel channel) {
+        return createAndAdmit(channel, SelectionKey.OP_CONNECT);
     }
     }
 
 
     /**
     /**
@@ -205,12 +215,14 @@ public abstract class IOLoop<M extends Message, S extends MessageStream<M>>
      * @param channel socket channel
      * @param channel socket channel
      * @param op      pending operations mask to be applied to the selection
      * @param op      pending operations mask to be applied to the selection
      *                key as a set of initial interestedOps
      *                key as a set of initial interestedOps
+     * @return newly created message stream
      */
      */
-    private synchronized void createAndAdmit(SocketChannel channel, int op) {
+    private synchronized S createAndAdmit(SocketChannel channel, int op) {
         S stream = createStream(channel);
         S stream = createStream(channel);
         streams.add(stream);
         streams.add(stream);
         newStreamRequests.add(new NewStreamRequest(stream, channel, op));
         newStreamRequests.add(new NewStreamRequest(stream, channel, op));
         selector.wakeup();
         selector.wakeup();
+        return stream;
     }
     }
 
 
     /**
     /**

@@ -10,6 +10,7 @@ import java.nio.channels.ByteChannel;
 import java.nio.channels.SelectionKey;
 import java.nio.channels.SelectionKey;
 import java.util.ArrayList;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.List;
+import java.util.Objects;
 
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkNotNull;
@@ -170,7 +171,7 @@ public abstract class MessageStream<M extends Message> {
     }
     }
 
 
     /**
     /**
-     * Reads, withouth blocking, a list of messages from the stream.
+     * Reads, without blocking, a list of messages from the stream.
      * The list will be empty if there were not messages pending.
      * The list will be empty if there were not messages pending.
      *
      *
      * @return list of messages or null if backing channel has been closed
      * @return list of messages or null if backing channel has been closed
@@ -262,7 +263,7 @@ public abstract class MessageStream<M extends Message> {
                 try {
                 try {
                     channel.write(outbound);
                     channel.write(outbound);
                 } catch (IOException e) {
                 } catch (IOException e) {
-                    if (!closed && !e.getMessage().equals("Broken pipe")) {
+                    if (!closed && !Objects.equals(e.getMessage(), "Broken pipe")) {
                         log.warn("Unable to write data", e);
                         log.warn("Unable to write data", e);
                         ioError = e;
                         ioError = e;
                     }
                     }

@@ -230,7 +230,7 @@ public class IOLoopTestClient {
         }
         }
 
 
         @Override
         @Override
-        protected void connect(SelectionKey key) {
+        protected void connect(SelectionKey key) throws IOException {
             super.connect(key);
             super.connect(key);
             TestMessageStream b = (TestMessageStream) key.attachment();
             TestMessageStream b = (TestMessageStream) key.attachment();
             Worker w = ((CustomIOLoop) b.loop()).worker;
             Worker w = ((CustomIOLoop) b.loop()).worker;