diff --git a/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/UiSharedTopologyModel.java b/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/UiSharedTopologyModel.java
index 50ebb06..4fbf707 100644
--- a/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/UiSharedTopologyModel.java
+++ b/web/gui/src/main/java/org/onosproject/ui/impl/topo/model/UiSharedTopologyModel.java
@@ -217,6 +217,22 @@
         return cache.accessRegion(id);
     }
 
+    /**
+     * Returns the null region.
+     *
+     * @return the null region
+     */
+    public UiRegion getNullRegion() {
+        return cache.nullRegion();
+    }
+
+    /**
+     * Refreshes the cache's internal state.
+     */
+    public void refresh() {
+        cache.refresh();
+    }
+
     // =====================================================================