diff --git a/core/api/src/main/java/org/onosproject/net/behaviour/upf/UpfEntity.java b/core/api/src/main/java/org/onosproject/net/behaviour/upf/UpfEntity.java
index ad1fbaa..81dd28a 100644
--- a/core/api/src/main/java/org/onosproject/net/behaviour/upf/UpfEntity.java
+++ b/core/api/src/main/java/org/onosproject/net/behaviour/upf/UpfEntity.java
@@ -24,6 +24,11 @@
 @Beta
 public interface UpfEntity {
     /**
+     * Default Application ID, to be used if application filtering is performed.
+     */
+    byte DEFAULT_APP_ID = 0;
+
+    /**
      * Returns the type of this entity.
      *
      * @return entity type