diff --git a/apps/tunnel/api/src/main/java/org/onosproject/incubator/net/domain/ExtraSubjectFactories.java b/apps/tunnel/api/src/main/java/org/onosproject/incubator/net/domain/ExtraSubjectFactories.java
new file mode 100644
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--- /dev/null
+++ b/apps/tunnel/api/src/main/java/org/onosproject/incubator/net/domain/ExtraSubjectFactories.java
@@ -0,0 +1,39 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * 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.incubator.net.domain;
+
+import com.google.common.annotations.Beta;
+import org.onosproject.net.config.SubjectFactory;
+
+/**
+ * Set of subject factories for potential configuration subjects.
+ */
+@Beta
+public final class ExtraSubjectFactories {
+
+    // Construction forbidden
+    private ExtraSubjectFactories() {
+    }
+
+    public static final SubjectFactory<IntentDomainId> INTENT_DOMAIN_SUBJECT_FACTORY =
+            new SubjectFactory<IntentDomainId>(IntentDomainId.class, "domains") {
+                @Override
+                public IntentDomainId createSubject(String key) {
+                    return IntentDomainId.valueOf(key);
+                }
+            };
+
+}