diff --git a/core/store/trivial/src/test/java/org/onlab/onos/store/trivial/impl/SimpleLinkStoreTest.java b/core/store/trivial/src/test/java/org/onlab/onos/store/trivial/impl/SimpleLinkStoreTest.java
new file mode 100644
index 0000000..eb4a312
--- /dev/null
+++ b/core/store/trivial/src/test/java/org/onlab/onos/store/trivial/impl/SimpleLinkStoreTest.java
@@ -0,0 +1,346 @@
+package org.onlab.onos.store.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));
+    }
+}