diff --git a/protocols/ovsdb/api/src/main/java/org/onosproject/ovsdb/controller/OvsdbConstant.java b/protocols/ovsdb/api/src/main/java/org/onosproject/ovsdb/controller/OvsdbConstant.java
index aea0845..cb2a31e 100644
--- a/protocols/ovsdb/api/src/main/java/org/onosproject/ovsdb/controller/OvsdbConstant.java
+++ b/protocols/ovsdb/api/src/main/java/org/onosproject/ovsdb/controller/OvsdbConstant.java
@@ -49,6 +49,7 @@
     /** Port table. */
     public static final String PORT = "Port";
     public static final String INTERFACES = "interfaces";
+    public static final String PORT_QOS = "qos";
 
     /** Interface table. */
     public static final String INTERFACE = "Interface";
@@ -70,6 +71,26 @@
     /** Mirror table. */
     public static final String MIRROR = "Mirror";
 
+    /* Qos table */
+    public static final String QOS = "QoS";
+    public static final String QUEUES = "queues";
+    public static final String CIR = "cir";
+    public static final String CBS = "cbs";
+    public static final String QOS_EXTERNAL_ID_KEY = "onos-qos-id";
+    public static final String QOS_TYPE_PREFIX = "linux-";
+    public static final String QOS_EGRESS_POLICER = "egress-policer";
+
+    /* Queue table */
+    public static final String QUEUE = "Queue";
+    public static final String MIN_RATE = "min-rate";
+    public static final String MAX_RATE = "max-rate";
+    public static final String BURST = "burst";
+    public static final String PRIORITY = "priority";
+    public static final String QUEUE_EXTERNAL_ID_KEY = "onos-queue-id";
+
+    /* external id */
+    public static final String EXTERNAL_ID = "external_ids";
+
     /** Ovsdb bridge name. */
     // TODO remove this particular bridge name from OVSDB provider
     public static final String INTEGRATION_BRIDGE = "br-int";