diff --git a/providers/host/src/main/java/org/onlab/onos/provider/host/impl/HostLocationProvider.java b/providers/host/src/main/java/org/onlab/onos/provider/host/impl/HostLocationProvider.java
index d22106c..d5e739f 100644
--- a/providers/host/src/main/java/org/onlab/onos/provider/host/impl/HostLocationProvider.java
+++ b/providers/host/src/main/java/org/onlab/onos/provider/host/impl/HostLocationProvider.java
@@ -85,6 +85,9 @@
 
         @Override
         public void process(PacketContext context) {
+            if (context == null) {
+                return;
+            }
             Ethernet eth = context.inPacket().parsed();
 
             VlanId vlan = VlanId.vlanId(eth.getVlanID());
diff --git a/providers/host/src/test/java/org.onlab.onos.provider.host.impl/HostLocationProviderTest.java b/providers/host/src/test/java/org.onlab.onos.provider.host.impl/HostLocationProviderTest.java
new file mode 100644
index 0000000..9ba6ce14
--- /dev/null
+++ b/providers/host/src/test/java/org.onlab.onos.provider.host.impl/HostLocationProviderTest.java
@@ -0,0 +1,237 @@
+package org.onlab.onos.provider.host.impl;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+
+import java.nio.ByteBuffer;
+import java.util.Set;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.onlab.onos.net.ConnectPoint;
+import org.onlab.onos.net.DeviceId;
+import org.onlab.onos.net.HostId;
+import org.onlab.onos.net.PortNumber;
+import org.onlab.onos.net.flow.TrafficTreatment;
+import org.onlab.onos.net.host.HostDescription;
+import org.onlab.onos.net.host.HostProvider;
+import org.onlab.onos.net.host.HostProviderRegistry;
+import org.onlab.onos.net.host.HostProviderService;
+import org.onlab.onos.net.packet.DefaultInboundPacket;
+import org.onlab.onos.net.packet.InboundPacket;
+import org.onlab.onos.net.packet.OutboundPacket;
+import org.onlab.onos.net.packet.PacketContext;
+import org.onlab.onos.net.packet.PacketProcessor;
+import org.onlab.onos.net.packet.PacketService;
+import org.onlab.onos.net.provider.AbstractProviderService;
+import org.onlab.onos.net.provider.ProviderId;
+import org.onlab.onos.net.topology.Topology;
+
+import org.onlab.onos.net.topology.TopologyServiceAdapter;
+import org.onlab.packet.ARP;
+import org.onlab.packet.Ethernet;
+import org.onlab.packet.MacAddress;
+import org.onlab.packet.VlanId;
+
+public class HostLocationProviderTest {
+
+    private static final Integer INPORT = 10;
+    private static final String DEV1 = "of:1";
+    private static final String DEV2 = "of:2";
+    private static final String DEV3 = "of:3";
+
+    private static final VlanId VLAN = VlanId.vlanId();
+    private static final MacAddress MAC = MacAddress.valueOf("00:00:11:00:00:01");
+    private static final MacAddress BCMAC = MacAddress.valueOf("ff:ff:ff:ff:ff:ff");
+    private static final byte[] IP = new byte[]{10, 0, 0, 1};
+
+    private final HostLocationProvider provider = new HostLocationProvider();
+    private final TestHostRegistry hostService = new TestHostRegistry();
+    private final TestTopologyService topoService = new TestTopologyService();
+    private final TestPacketService packetService = new TestPacketService();
+
+    private PacketProcessor testProcessor;
+    private TestHostProviderService providerService;
+
+    @Before
+    public void setUp() {
+        provider.providerRegistry = hostService;
+        provider.topologyService = topoService;
+        provider.pktService = packetService;
+
+        provider.activate();
+
+    }
+
+    @Test
+    public void basics() {
+        assertNotNull("registration expected", providerService);
+        assertEquals("incorrect provider", provider, providerService.provider());
+    }
+
+    @Test
+    public void events() {
+        // new host
+
+
+        testProcessor.process(new TestPacketContext(DEV1));
+        assertNotNull("new host expected", providerService.added);
+        assertNull("host motion unexpected", providerService.moved);
+
+        // the host moved to new switch
+        testProcessor.process(new TestPacketContext(DEV2));
+        assertNotNull("host motion expected", providerService.moved);
+
+        // the host was misheard on a spine
+        testProcessor.process(new TestPacketContext(DEV3));
+        assertNull("host misheard on spine switch", providerService.spine);
+    }
+
+    @After
+    public void tearDown() {
+        provider.deactivate();
+        provider.providerRegistry = null;
+
+    }
+
+    private class TestHostRegistry implements HostProviderRegistry {
+
+        @Override
+        public HostProviderService register(HostProvider provider) {
+            providerService = new TestHostProviderService(provider);
+            return providerService;
+        }
+
+        @Override
+        public void unregister(HostProvider provider) {
+        }
+
+        @Override
+        public Set<ProviderId> getProviders() {
+            return null;
+        }
+
+    }
+
+    private class TestHostProviderService
+            extends AbstractProviderService<HostProvider>
+            implements HostProviderService {
+
+        DeviceId added = null;
+        DeviceId moved = null;
+        DeviceId spine = null;
+
+        protected TestHostProviderService(HostProvider provider) {
+            super(provider);
+        }
+
+        @Override
+        public void hostDetected(HostId hostId, HostDescription hostDescription) {
+            DeviceId descr = hostDescription.location().deviceId();
+            if (added == null) {
+                added = descr;
+            } else if ((moved == null) && !descr.equals(added)) {
+                moved = descr;
+            } else {
+                spine = descr;
+            }
+        }
+
+        @Override
+        public void hostVanished(HostId hostId) {
+        }
+
+    }
+
+    private class TestPacketService implements PacketService {
+
+        @Override
+        public void addProcessor(PacketProcessor processor, int priority) {
+            testProcessor = processor;
+        }
+
+        @Override
+        public void removeProcessor(PacketProcessor processor) {
+
+        }
+
+        @Override
+        public void emit(OutboundPacket packet) {
+
+        }
+    }
+
+
+    private class TestTopologyService extends TopologyServiceAdapter {
+        @Override
+        public boolean isInfrastructure(Topology topology,
+                                        ConnectPoint connectPoint) {
+            //simulate DPID3 as an infrastructure switch
+            if ((connectPoint.deviceId()).equals(DeviceId.deviceId(DEV3))) {
+                return true;
+            }
+            return false;
+        }
+    }
+
+    private class TestPacketContext implements PacketContext {
+
+        private final String deviceId;
+
+        public TestPacketContext(String deviceId) {
+            this.deviceId = deviceId;
+        }
+
+        @Override
+        public long time() {
+            return 0;
+        }
+
+        @Override
+        public InboundPacket inPacket() {
+            ARP arp = new ARP();
+            arp.setSenderProtocolAddress(IP)
+                    .setSenderHardwareAddress(MAC.toBytes())
+                    .setTargetHardwareAddress(BCMAC.toBytes())
+                    .setTargetProtocolAddress(IP);
+
+            Ethernet eth = new Ethernet();
+            eth.setEtherType(Ethernet.TYPE_ARP)
+                    .setVlanID(VLAN.toShort())
+                    .setSourceMACAddress(MAC.toBytes())
+                    .setDestinationMACAddress(BCMAC.getAddress())
+                    .setPayload(arp);
+            ConnectPoint receivedFrom = new ConnectPoint(DeviceId.deviceId(deviceId),
+                                                         PortNumber.portNumber(INPORT));
+            return new DefaultInboundPacket(receivedFrom, eth,
+                                            ByteBuffer.wrap(eth.serialize()));
+        }
+
+        @Override
+        public OutboundPacket outPacket() {
+            return null;
+        }
+
+        @Override
+        public TrafficTreatment.Builder treatmentBuilder() {
+            return null;
+        }
+
+        @Override
+        public void send() {
+
+        }
+
+        @Override
+        public boolean block() {
+            return false;
+        }
+
+        @Override
+        public boolean isHandled() {
+            return false;
+        }
+    }
+}
diff --git a/providers/lldp/src/main/java/org/onlab/onos/provider/lldp/impl/LLDPLinkProvider.java b/providers/lldp/src/main/java/org/onlab/onos/provider/lldp/impl/LLDPLinkProvider.java
index acffe54..f611496 100644
--- a/providers/lldp/src/main/java/org/onlab/onos/provider/lldp/impl/LLDPLinkProvider.java
+++ b/providers/lldp/src/main/java/org/onlab/onos/provider/lldp/impl/LLDPLinkProvider.java
@@ -152,6 +152,9 @@
 
         @Override
         public void process(PacketContext context) {
+            if (context == null) {
+                return;
+            }
             LinkDiscovery ld = discoverers.get(
                     context.inPacket().receivedFrom().deviceId());
             if (ld == null) {