diff --git a/api/src/main/java/org/onosproject/olt/AccessDeviceEvent.java b/api/src/main/java/org/onosproject/olt/AccessDeviceEvent.java
new file mode 100644
index 0000000..7eda5a9
--- /dev/null
+++ b/api/src/main/java/org/onosproject/olt/AccessDeviceEvent.java
@@ -0,0 +1,88 @@
+package org.onosproject.olt;
+
+import org.onlab.packet.VlanId;
+import org.onosproject.event.AbstractEvent;
+import org.onosproject.net.DeviceId;
+
+import java.util.Optional;
+
+/**
+ * Describes an access device event.
+ */
+public class AccessDeviceEvent extends AbstractEvent<AccessDeviceEvent.Type, DeviceId> {
+
+    private final Optional<VlanId> sVlan;
+    private final Optional<VlanId> cVlan;
+
+    public enum Type {
+        /**
+         * A subscriber was registered and provisioned.
+         */
+        SUBSCRIBER_REGISTERED,
+
+        /**
+         * A subscriber was unregistered and deprovisioned.
+         */
+        SUBSCRIBER_UNREGISTERED,
+
+        /**
+         * An access device connected.
+         */
+        DEVICE_CONNECTED,
+
+        /**
+         * An access device disconnected.
+         */
+        DEVICE_DISCONNECTED
+
+    }
+
+    /**
+     *
+     * Creates an event of a given type and for the specified device,
+     * along with the cVlanId and sVlanId. The vlan fields may not be provisioned
+     * if the event is related to the access device (dis)connection.
+     *
+     * @param type the event type
+     * @param deviceId the device id
+     * @param sVlanId the service vlan
+     * @param cVlanId the customer vlan
+     */
+    public AccessDeviceEvent(Type type, DeviceId deviceId,
+                             VlanId sVlanId,
+                             VlanId cVlanId) {
+        super(type, deviceId);
+        this.sVlan = Optional.ofNullable(sVlanId);
+        this.cVlan = Optional.ofNullable(cVlanId);
+    }
+
+    /**
+     *
+     * Creates an event of a given type and for the specified device, and timestamp
+     * along with the cVlanId and sVlanId. The vlan fields may not be provisioned
+     * if the event is related to the access device (dis)connection.
+     *
+     * @param type the event type
+     * @param deviceId the device id
+     * @param time a timestamp
+     * @param sVlanId the service vlan
+     * @param cVlanId the customer vlan
+     */
+    protected AccessDeviceEvent(Type type, DeviceId deviceId, long time,
+                                VlanId sVlanId,
+                                VlanId cVlanId) {
+        super(type, deviceId, time);
+        this.sVlan = Optional.ofNullable(sVlanId);
+        this.cVlan = Optional.ofNullable(cVlanId);
+
+    }
+
+    public Optional<VlanId> sVlanId() {
+        return sVlan;
+    }
+
+    public Optional<VlanId> cVlanId() {
+        return cVlan;
+    }
+
+}