diff --git a/apps/openstacknode/api/src/main/java/org/onosproject/openstacknode/api/Constants.java b/apps/openstacknode/api/src/main/java/org/onosproject/openstacknode/api/Constants.java
index b7ca1f5..0422c65 100644
--- a/apps/openstacknode/api/src/main/java/org/onosproject/openstacknode/api/Constants.java
+++ b/apps/openstacknode/api/src/main/java/org/onosproject/openstacknode/api/Constants.java
@@ -26,7 +26,8 @@
     public static final String INTEGRATION_BRIDGE = "br-int";
     public static final String TUNNEL_BRIDGE = "br-tun";
     public static final String ROUTER_BRIDGE = "br-router";
-    public static final String DEFAULT_TUNNEL = "vxlan";
+    public static final String VXLAN_TUNNEL = "vxlan";
+    public static final String GRE_TUNNEL = "gre";
     public static final String PATCH_INTG_BRIDGE = "patch-intg";
     public static final String PATCH_ROUT_BRIDGE = "patch-rout";
     public static final String GATEWAY = "GATEWAY";