diff --git a/apps/openstacknetworking/src/main/java/org/onosproject/openstacknetworking/api/InstancePortService.java b/apps/openstacknetworking/src/main/java/org/onosproject/openstacknetworking/api/InstancePortService.java
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+++ b/apps/openstacknetworking/src/main/java/org/onosproject/openstacknetworking/api/InstancePortService.java
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * 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.openstacknetworking.api;
+
+import org.onlab.packet.IpAddress;
+import org.onlab.packet.MacAddress;
+import org.onosproject.event.ListenerService;
+
+import java.util.Set;
+
+/**
+ * Service for interacting with the inventory of instance ports.
+ */
+public interface InstancePortService
+        extends ListenerService<InstancePortEvent, InstancePortListener> {
+
+    /**
+     * Returns instance port with the given MAC address.
+     *
+     * @param macAddress mac address
+     * @return instance port; null if not found
+     */
+    InstancePort instancePort(MacAddress macAddress);
+
+    /**
+     * Returns instance port with the given IP address in the given OpenStack network.
+     *
+     * @param ipAddress ip address
+     * @param osNetId   openstack network id
+     * @return instance port; null if not found
+     */
+    InstancePort instancePort(IpAddress ipAddress, String osNetId);
+
+    /**
+     * Returns instance port with the given openstack port ID.
+     *
+     * @param osPortId openstack port id
+     * @return instance port; null if not found
+     */
+    InstancePort instancePort(String osPortId);
+
+    /**
+     * Returns all instance ports.
+     *
+     * @return set of instance ports; empty list if no port exists
+     */
+    Set<InstancePort> instancePorts();
+
+    /**
+     * Returns instance ports in the given OpenStack network.
+     *
+     * @param osNetId openstack network
+     * @return set of instance ports; empty list if no port exists
+     */
+    Set<InstancePort> instancePorts(String osNetId);
+}