diff --git a/core/api/src/main/java/org/onosproject/net/host/HostProviderService.java b/core/api/src/main/java/org/onosproject/net/host/HostProviderService.java
index 41eb504..b324ad0 100644
--- a/core/api/src/main/java/org/onosproject/net/host/HostProviderService.java
+++ b/core/api/src/main/java/org/onosproject/net/host/HostProviderService.java
@@ -16,6 +16,7 @@
 package org.onosproject.net.host;
 
 import org.onlab.packet.IpAddress;
+import org.onlab.packet.MacAddress;
 import org.onosproject.net.HostId;
 import org.onosproject.net.HostLocation;
 import org.onosproject.net.provider.ProviderService;
@@ -57,4 +58,23 @@
      * @param location location of host that vanished
      */
     void removeLocationFromHost(HostId hostId, HostLocation location);
+
+    /**
+     * Notifies HostProviderService the beginning of pending host location verification and
+     * retrieves the unique MAC address for the probe.
+     *
+     * @param hostId ID of the host
+     * @param hostLocation the host location that is under verification
+     * @return probeMac, the source MAC address ONOS uses to probe the host
+     */
+    default MacAddress addPendingHostLocation(HostId hostId, HostLocation hostLocation) {
+        return MacAddress.NONE;
+    }
+
+    /**
+     * Notifies HostProviderService the end of pending host location verification.
+     *
+     * @param probeMac the source MAC address ONOS uses to probe the host
+     */
+    default void removePendingHostLocation(MacAddress probeMac) {}
 }
diff --git a/core/api/src/main/java/org/onosproject/net/host/HostStore.java b/core/api/src/main/java/org/onosproject/net/host/HostStore.java
index 1529c68..6e98d95 100644
--- a/core/api/src/main/java/org/onosproject/net/host/HostStore.java
+++ b/core/api/src/main/java/org/onosproject/net/host/HostStore.java
@@ -134,4 +134,22 @@
      */
     Set<Host> getConnectedHosts(DeviceId deviceId);
 
+    /**
+     * Notifies HostStore the beginning of pending host location verification and
+     * retrieves the unique MAC address for the probe.
+     *
+     * @param hostId ID of the host
+     * @param hostLocation the host location that is under verification
+     * @return probeMac, the source MAC address ONOS uses to probe the host
+     */
+    default MacAddress addPendingHostLocation(HostId hostId, HostLocation hostLocation) {
+        return MacAddress.NONE;
+    }
+
+    /**
+     * Notifies HostStore the end of pending host location verification.
+     *
+     * @param probeMac the source MAC address ONOS uses to probe the host
+     */
+    default void removePendingHostLocation(MacAddress probeMac) {}
 }
diff --git a/core/net/src/main/java/org/onosproject/net/host/impl/HostManager.java b/core/net/src/main/java/org/onosproject/net/host/impl/HostManager.java
index cda9e04..f6c5856 100644
--- a/core/net/src/main/java/org/onosproject/net/host/impl/HostManager.java
+++ b/core/net/src/main/java/org/onosproject/net/host/impl/HostManager.java
@@ -455,6 +455,16 @@
             store.removeLocation(hostId, location);
         }
 
+        @Override
+        public MacAddress addPendingHostLocation(HostId hostId, HostLocation hostLocation) {
+            return store.addPendingHostLocation(hostId, hostLocation);
+        }
+
+        @Override
+        public void removePendingHostLocation(MacAddress probeMac) {
+            store.removePendingHostLocation(probeMac);
+        }
+
         private boolean allowedToChange(HostId hostId) {
             // Disallow removing inexistent host or host provided by others
             Host host = store.getHost(hostId);
diff --git a/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java b/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java
index bc0dd00..b5dcc76 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/host/impl/DistributedHostStore.java
@@ -15,6 +15,9 @@
  */
 package org.onosproject.store.host.impl;
 
+import com.google.common.cache.Cache;
+import com.google.common.cache.CacheBuilder;
+import com.google.common.cache.RemovalNotification;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
 
@@ -49,6 +52,7 @@
 import org.onosproject.store.service.Serializer;
 import org.onosproject.store.service.StorageService;
 import org.onosproject.store.service.DistributedPrimitive.Status;
+import org.onosproject.store.service.Versioned;
 import org.slf4j.Logger;
 
 import java.util.Collection;
@@ -58,7 +62,10 @@
 import java.util.Objects;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
@@ -88,29 +95,67 @@
     private ConsistentMap<HostId, DefaultHost> hostsConsistentMap;
     private Map<HostId, DefaultHost> hosts;
     private Map<IpAddress, Set<Host>> hostsByIp;
-
     private MapEventListener<HostId, DefaultHost> hostLocationTracker =
             new HostLocationTracker();
 
+    private ConsistentMap<MacAddress, PendingHostLocation> pendingHostsConsistentMap;
+    private Map<MacAddress, PendingHostLocation> pendingHosts;
+    private MapEventListener<MacAddress, PendingHostLocation> pendingHostListener =
+            new PendingHostListener();
+
     private ScheduledExecutorService executor;
 
     private Consumer<Status> statusChangeListener;
 
+    // TODO make this configurable
+    private static final int PROBE_TIMEOUT_MS = 1000;
+
+    private Cache<MacAddress, PendingHostLocation> pendingHostsCache = CacheBuilder.newBuilder()
+            .expireAfterWrite(PROBE_TIMEOUT_MS, TimeUnit.MILLISECONDS)
+            .removalListener((RemovalNotification<MacAddress, PendingHostLocation> notification) -> {
+                switch (notification.getCause()) {
+                    case EXPIRED:
+                        PendingHostLocation expired = notification.getValue();
+                        if (expired != null) {
+                            log.info("Evict timeout probe {} from pendingHostLocations", notification.getValue());
+                            timeoutPendingHostLocation(notification.getKey());
+                        }
+                        break;
+                    case EXPLICIT:
+                        break;
+                    default:
+                        log.warn("Remove {} from pendingHostLocations for unexpected reason {}",
+                                notification.getKey(), notification.getCause());
+                }
+            }).build();
+
+    private ScheduledExecutorService cacheCleaner = Executors.newSingleThreadScheduledExecutor();
+
     @Activate
     public void activate() {
         KryoNamespace.Builder hostSerializer = KryoNamespace.newBuilder()
                 .register(KryoNamespaces.API);
-
         hostsConsistentMap = storageService.<HostId, DefaultHost>consistentMapBuilder()
                 .withName("onos-hosts")
                 .withRelaxedReadConsistency()
                 .withSerializer(Serializer.using(hostSerializer.build()))
                 .build();
-
+        hostsConsistentMap.addListener(hostLocationTracker);
         hosts = hostsConsistentMap.asJavaMap();
 
+        KryoNamespace.Builder pendingHostSerializer = KryoNamespace.newBuilder()
+                .register(KryoNamespaces.API)
+                .register(PendingHostLocation.class);
+        pendingHostsConsistentMap = storageService.<MacAddress, PendingHostLocation>consistentMapBuilder()
+                .withName("onos-hosts-pending")
+                .withRelaxedReadConsistency()
+                .withSerializer(Serializer.using(pendingHostSerializer.build()))
+                .build();
+        pendingHostsConsistentMap.addListener(pendingHostListener);
+        pendingHosts = pendingHostsConsistentMap.asJavaMap();
 
-        hostsConsistentMap.addListener(hostLocationTracker);
+        cacheCleaner.scheduleAtFixedRate(pendingHostsCache::cleanUp, 0,
+                PROBE_TIMEOUT_MS, TimeUnit.MILLISECONDS);
 
         executor = newSingleThreadScheduledExecutor(groupedThreads("onos/hosts", "store", log));
         statusChangeListener = status -> {
@@ -127,6 +172,8 @@
     public void deactivate() {
         hostsConsistentMap.removeListener(hostLocationTracker);
 
+        cacheCleaner.shutdown();
+
         log.info("Stopped");
     }
 
@@ -335,6 +382,32 @@
         return ImmutableSet.copyOf(filtered);
     }
 
+    @Override
+    public MacAddress addPendingHostLocation(HostId hostId, HostLocation hostLocation) {
+        // Use ONLab OUI (3 bytes) + atomic counter (3 bytes) as the source MAC of the probe
+        long nextIndex = storageService.getAtomicCounter("onos-hosts-probe-index").getAndIncrement();
+        MacAddress probeMac = MacAddress.valueOf(MacAddress.NONE.toLong() + nextIndex);
+        PendingHostLocation phl = new PendingHostLocation(hostId, hostLocation);
+
+        pendingHostsCache.put(probeMac, phl);
+        pendingHosts.put(probeMac, phl);
+
+        return probeMac;
+    }
+
+    @Override
+    public void removePendingHostLocation(MacAddress probeMac) {
+        pendingHostsCache.invalidate(probeMac);
+        pendingHosts.remove(probeMac);
+    }
+
+    private void timeoutPendingHostLocation(MacAddress probeMac) {
+        pendingHosts.computeIfPresent(probeMac, (k, v) -> {
+            v.setExpired(true);
+            return v;
+        });
+    }
+
     private Set<Host> filter(Collection<DefaultHost> collection, Predicate<DefaultHost> predicate) {
         return collection.stream().filter(predicate).collect(Collectors.toSet());
     }
@@ -418,4 +491,28 @@
             }
         }
     }
+
+    private class PendingHostListener implements MapEventListener<MacAddress, PendingHostLocation> {
+        @Override
+        public void event(MapEvent<MacAddress, PendingHostLocation> event) {
+            Versioned<PendingHostLocation> newValue = event.newValue();
+            switch (event.type()) {
+                case INSERT:
+                    break;
+                case UPDATE:
+                    if (newValue.value().expired()) {
+                        Executor locationRemover = Executors.newSingleThreadScheduledExecutor();
+                        locationRemover.execute(() -> {
+                            pendingHosts.remove(event.key());
+                            removeLocation(newValue.value().hostId(), newValue.value().location());
+                        });
+                    }
+                    break;
+                case REMOVE:
+                    break;
+                default:
+                    log.warn("Unknown map event type: {}", event.type());
+            }
+        }
+    }
 }
diff --git a/core/store/dist/src/main/java/org/onosproject/store/host/impl/PendingHostLocation.java b/core/store/dist/src/main/java/org/onosproject/store/host/impl/PendingHostLocation.java
new file mode 100644
index 0000000..de538f5
--- /dev/null
+++ b/core/store/dist/src/main/java/org/onosproject/store/host/impl/PendingHostLocation.java
@@ -0,0 +1,108 @@
+/*
+ * Copyright 2017-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.store.host.impl;
+
+import org.onosproject.net.HostId;
+import org.onosproject.net.HostLocation;
+
+import java.util.Objects;
+
+import static com.google.common.base.MoreObjects.toStringHelper;
+
+/**
+ * Internal data structure to record the info of a host with location that is under verification.
+ */
+class PendingHostLocation {
+    private HostId hostId;
+    private HostLocation location;
+    private boolean expired;
+
+    /**
+     * Constructs PendingHostLocation.
+     *
+     * @param hostId Host ID
+     * @param location location to be verified
+     */
+    PendingHostLocation(HostId hostId, HostLocation location) {
+        this.hostId = hostId;
+        this.location = location;
+        this.expired = false;
+    }
+
+    /**
+     * Gets HostId of this entry.
+     *
+     * @return host id
+     */
+    HostId hostId() {
+        return hostId;
+    }
+
+    /**
+     * Gets HostLocation of this entry.
+     *
+     * @return host location
+     */
+    HostLocation location() {
+        return location;
+    }
+
+    /**
+     * Determine whether this probe is expired or not.
+     *
+     * @return true if this entry is expired and waiting to be removed from the cache
+     */
+    boolean expired() {
+        return expired;
+    }
+
+    /**
+     * Sets whether this probe is expired or not.
+     *
+     * @param expired true if this entry is expired and waiting to be removed from the cache
+     */
+    void setExpired(boolean expired) {
+        this.expired = expired;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof PendingHostLocation)) {
+            return false;
+        }
+        PendingHostLocation that = (PendingHostLocation) o;
+        return (Objects.equals(this.hostId, that.hostId) &&
+                Objects.equals(this.location, that.location) &&
+                Objects.equals(this.expired, that.expired));
+    }
+    @Override
+    public int hashCode() {
+        return Objects.hash(hostId, location, expired);
+    }
+
+    @Override
+    public String toString() {
+        return toStringHelper(getClass())
+                .add("hostId", hostId)
+                .add("location", location)
+                .add("expired", expired)
+                .toString();
+    }
+}