[SEBA-624] Implementation of radius server operational status

Cherry-picked from aaa-1.10

Change-Id: I3b70ddfc45c4b9e57c587df671088580c7426a89
diff --git a/api/src/main/java/org/opencord/aaa/RadiusOperationalStatusEvent.java b/api/src/main/java/org/opencord/aaa/RadiusOperationalStatusEvent.java
new file mode 100644
index 0000000..7ba9534
--- /dev/null
+++ b/api/src/main/java/org/opencord/aaa/RadiusOperationalStatusEvent.java
@@ -0,0 +1,32 @@
+/*
+ * 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.opencord.aaa;
+
+import org.onosproject.event.AbstractEvent;
+
+public class RadiusOperationalStatusEvent extends
+              AbstractEvent<RadiusOperationalStatusEvent.Type, String> {
+
+    public RadiusOperationalStatusEvent(Type type, String subject) {
+         super(type, subject);
+    }
+
+    public enum Type {
+         RADIUS_OPERATIONAL_STATUS
+    }
+
+}