diff --git a/drivers/fujitsu/src/main/java/org/onosproject/drivers/fujitsu/FujitsuVoltFwdlConfig.java b/drivers/fujitsu/src/main/java/org/onosproject/drivers/fujitsu/FujitsuVoltFwdlConfig.java
index 51cc1ee..4346512 100644
--- a/drivers/fujitsu/src/main/java/org/onosproject/drivers/fujitsu/FujitsuVoltFwdlConfig.java
+++ b/drivers/fujitsu/src/main/java/org/onosproject/drivers/fujitsu/FujitsuVoltFwdlConfig.java
@@ -43,9 +43,8 @@
     private static final String MEMBER = "member";
     private static final String IMAGE_NAME = "image-name";
     private static final String REBOOT_MODE = "reboot-mode";
-    private int pon;
-    private int onu;
-
+    private static final String AUTO = "auto";
+    private static final String COMMA = ",";
 
     @Override
     public String upgradeFirmwareOndemand(String target) {
@@ -61,67 +60,84 @@
             log.warn("Not master for {} Use {} to execute command",
                      ncDeviceId,
                      mastershipService.getMasterFor(ncDeviceId));
-            return reply;
+            return null;
         }
 
-        String[] data = target.split(":");
-        if ((data.length < 2) || (data.length > 3)) {
+        String[] data = target.split(COLON);
+        if ((data.length < TWO) || (data.length > THREE)) {
             log.error("Invalid number of arguments");
-            return reply;
+            return null;
         }
 
-        String[] onuList = data[1].split(",");
-        if (onuList.length == 0) {
+        String[] onuList = data[SECOND_PART].split(COMMA);
+        if (onuList.length == ZERO) {
             log.error("No ONU listed");
-            return reply;
+            return null;
+        }
+
+        if ((data.length > TWO) && (!AUTO.equals(data[THIRD_PART]))) {
+            log.error("Invalid reboot-mode {}", data[THIRD_PART]);
+            return null;
         }
 
         try {
             StringBuilder request = new StringBuilder();
-            request.append(ANGLE_LEFT).append(ONDEMAND_FIRMWARE_UPGRADE).append(SPACE);
-            request.append(VOLT_NE_NAMESPACE).append(ANGLE_RIGHT).append(NEW_LINE);
+            request.append(ANGLE_LEFT + ONDEMAND_FIRMWARE_UPGRADE + SPACE);
+            request.append(VOLT_NE_NAMESPACE + ANGLE_RIGHT + NEW_LINE);
             request.append(buildStartTag(PARTICIPANT_LIST));
 
-            for (count = 0; count < onuList.length; count++) {
-                String[] onuId = onuList[count].split("-");
-                if (onuId.length != 2) {
+            for (count = ZERO; count < onuList.length; count++) {
+                String[] onuId = onuList[count].split(HYPHEN);
+                if (onuId.length != TWO) {
                     log.error("Invalid ONU identifier");
-                    return reply;
+                    return null;
                 }
 
                 try {
-                    pon = Integer.parseInt(onuId[0]);
-                    onu = Integer.parseInt(onuId[1]);
+                    int pon;
+                    pon = Integer.parseInt(onuId[FIRST_PART]);
+                    if (pon <= ZERO) {
+                        log.error("Invalid integer for ponlink-id:{}", onuId[FIRST_PART]);
+                        return null;
+                    }
+                    int onu;
+                    onu = Integer.parseInt(onuId[SECOND_PART]);
+                    if (onu <= ZERO) {
+                        log.error("Invalid integer for onu-id:{}", onuId[SECOND_PART]);
+                        return null;
+                    }
                 } catch (NumberFormatException e) {
                     log.error("Non-number input");
-                    return reply;
+                    return null;
                 }
 
-                request.append(buildStartTag(MEMBER));
-                request.append(buildStartTag(PONLINK_ID));
-                request.append(onuId[0]);
-                request.append(buildEndTag(PONLINK_ID));
-                request.append(buildStartTag(ONU_ID));
-                request.append(onuId[1]);
-                request.append(buildEndTag(ONU_ID));
-                request.append(buildEndTag(MEMBER));
+                request.append(buildStartTag(MEMBER))
+                    .append(buildStartTag(PONLINK_ID))
+                    .append(onuId[FIRST_PART])
+                    .append(buildEndTag(PONLINK_ID))
+                    .append(buildStartTag(ONU_ID))
+                    .append(onuId[SECOND_PART])
+                    .append(buildEndTag(ONU_ID))
+                    .append(buildEndTag(MEMBER));
             }
-            request.append(buildEndTag(PARTICIPANT_LIST));
-            request.append(buildStartTag(IMAGE_NAME));
-            request.append(data[0]);
-            request.append(buildEndTag(IMAGE_NAME));
-            if (data.length == 3) {
-                request.append(buildStartTag(REBOOT_MODE));
-                request.append(data[2]);
-                request.append(buildEndTag(REBOOT_MODE));
+            request.append(buildEndTag(PARTICIPANT_LIST))
+                .append(buildStartTag(IMAGE_NAME))
+                .append(data[FIRST_PART])
+                .append(buildEndTag(IMAGE_NAME));
+            if (data.length == THREE) {
+                request.append(buildStartTag(REBOOT_MODE))
+                    .append(data[THIRD_PART])
+                    .append(buildEndTag(REBOOT_MODE));
             }
             request.append(buildEndTag(ONDEMAND_FIRMWARE_UPGRADE));
 
-            reply = controller.
-                    getDevicesMap().get(ncDeviceId).getSession().
-                    doWrappedRpc(request.toString());
+            reply = controller
+                    .getDevicesMap()
+                    .get(ncDeviceId)
+                    .getSession()
+                    .doWrappedRpc(request.toString());
         } catch (IOException e) {
-            log.error("Cannot communicate to device {} exception ", ncDeviceId, e);
+            log.error("Cannot communicate to device {} exception {}", ncDeviceId, e);
         }
         return reply;
     }
diff --git a/drivers/fujitsu/src/test/java/org/onosproject/drivers/fujitsu/FujitsuVoltFwdlConfigTest.java b/drivers/fujitsu/src/test/java/org/onosproject/drivers/fujitsu/FujitsuVoltFwdlConfigTest.java
new file mode 100644
index 0000000..0377070
--- /dev/null
+++ b/drivers/fujitsu/src/test/java/org/onosproject/drivers/fujitsu/FujitsuVoltFwdlConfigTest.java
@@ -0,0 +1,199 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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.drivers.fujitsu;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertNotNull;
+import static org.onosproject.drivers.fujitsu.FujitsuVoltXmlUtilityMock.*;
+
+
+/**
+ * Unit tests for methods of FujitsuVoltFwdlConfig.
+ */
+public class FujitsuVoltFwdlConfigTest {
+
+    private final FujitsuNetconfSessionListenerTest listener = new InternalSessionListener();
+
+    private static final String TEST_ONDEMAND_FIRMWARE_UPGRADE = "ondemand-firmware-upgrade";
+    private static final String TEST_PARTICIPANT_LIST = "participant-list";
+    private static final String TEST_MEMBER = "member";
+    private static final String TEST_IMAGE_NAME = "image-name";
+    private static final String TEST_REBOOT_MODE = "reboot-mode";
+    private static final String TEST_COMMA = ",";
+
+    private static final String TEST_ONDEMAND_FWDL_WITH_NAMESPACE =
+            TEST_ANGLE_LEFT + TEST_ONDEMAND_FIRMWARE_UPGRADE +
+            TEST_SPACE + TEST_VOLT_NE_NAMESPACE;
+
+    private static final String[] INVALID_ONDEMAND_FWDL_TCS = {
+        "xy1-b:a1-1",
+        "AAA:1-2,--1",
+        "CcC:s-1,2-2,3-2:auto",
+        "xYZam:1-1,2-2,3-3:false",
+        "JKml901:16-1-1,2-16:a-2",
+        "abc:&AA-1,11-2:auto",
+        "abc:xyz:-1-1",
+        "@bcf11:xyz:auto",
+        "FJ123:1-1&5-2:auto",
+    };
+    private static final String[] VALID_ONDEMAND_FWDL_TCS = {
+        "Fujitsu123:1-2",
+        "abcDE90f:16-11,1-1,17-3:auto",
+        "fujitsuONU12:1-1,2-2,3-3,4-4,5-5,6-6,7-7",
+    };
+    private Integer currentKey;
+    private FujitsuNetconfControllerMock controller;
+    private FujitsuDriverHandlerAdapter driverHandler;
+    private FujitsuVoltFwdlConfig voltConfig;
+
+    @Before
+    public void setUp() throws Exception {
+        controller = new FujitsuNetconfControllerMock();
+        driverHandler = controller.setUp(listener);
+        voltConfig = new FujitsuVoltFwdlConfig();
+        voltConfig.setHandler(driverHandler);
+    }
+
+    /**
+     * Run to verify handling of invalid input for rpc operation.
+     */
+    @Test
+    public void testInvalidOndemandFirmwareUpgradeInput() throws Exception {
+        String reply;
+        String target;
+
+        for (int i = ZERO; i < INVALID_ONDEMAND_FWDL_TCS.length; i++) {
+            target = INVALID_ONDEMAND_FWDL_TCS[i];
+            reply = voltConfig.upgradeFirmwareOndemand(target);
+            assertNull("Incorrect response for INVALID_ONDEMAND_FWDL_TCS", reply);
+        }
+    }
+
+    /**
+     * Run to verify handling of valid input for rpc operation.
+     */
+    @Test
+    public void testValidOndemandFirmwareUpgrade() throws Exception {
+        String reply;
+        String target;
+
+        for (int i = ZERO; i < VALID_ONDEMAND_FWDL_TCS.length; i++) {
+            target = VALID_ONDEMAND_FWDL_TCS[i];
+            currentKey = i;
+            reply = voltConfig.upgradeFirmwareOndemand(target);
+            assertNotNull("Incorrect response for VALID_ONDEMAND_FWDL_TCS", reply);
+        }
+    }
+
+    /**
+     * Verifies XML request string by comparing with generated string.
+     *
+     * @param request XML string for rpc operation
+     * @return true or false
+     */
+    private boolean verifyWrappedRpcRequest(String request) {
+        StringBuilder rpc = new StringBuilder();
+        String target = VALID_ONDEMAND_FWDL_TCS[currentKey];
+        String[] data = target.split(TEST_COLON);
+        String[] onuList = data[SECOND_PART].split(TEST_COMMA);
+        int count;
+
+        rpc.append(TEST_ANGLE_LEFT + TEST_ONDEMAND_FIRMWARE_UPGRADE + TEST_SPACE);
+        rpc.append(TEST_VOLT_NE_NAMESPACE + TEST_ANGLE_RIGHT + TEST_NEW_LINE);
+
+        rpc.append(startTag(TEST_PARTICIPANT_LIST));
+        for (count = ZERO; count < onuList.length; count++) {
+            String[] onuId = onuList[count].split(TEST_HYPHEN);
+            rpc.append(startTag(TEST_MEMBER))
+                .append(startTag(TEST_PONLINK_ID))
+                .append(onuId[FIRST_PART])
+                .append(endTag(TEST_PONLINK_ID))
+                .append(startTag(TEST_ONU_ID))
+                .append(onuId[SECOND_PART])
+                .append(endTag(TEST_ONU_ID))
+                .append(endTag(TEST_MEMBER));
+        }
+        rpc.append(endTag(TEST_PARTICIPANT_LIST))
+            .append(startTag(TEST_IMAGE_NAME))
+            .append(data[FIRST_PART])
+            .append(endTag(TEST_IMAGE_NAME));
+        if (data.length == THREE) {
+            rpc.append(startTag(TEST_REBOOT_MODE))
+                .append(data[THIRD_PART])
+                .append(endTag(TEST_REBOOT_MODE));
+        }
+        rpc.append(endTag(TEST_ONDEMAND_FIRMWARE_UPGRADE));
+
+        String testRequest = rpc.toString();
+        String regex = TEST_WHITESPACES_REGEX;
+        int index = rpc.indexOf(regex);
+        while (index >= ZERO) {
+            testRequest = rpc.replace(index, index + regex.length(), TEST_EMPTY_STRING).toString();
+            request = request.replaceAll(regex, TEST_EMPTY_STRING);
+        }
+        boolean result = request.equals(testRequest);
+        assertTrue("Does not match with generated string", result);
+        return result;
+    }
+
+    /**
+     * Internal listener for device service events.
+     */
+    private class InternalSessionListener implements FujitsuNetconfSessionListenerTest {
+        @Override
+        public boolean verifyEditConfig(String request) {
+            return false;
+        }
+
+        @Override
+        public boolean verifyEditConfig(String target, String mode, String request) {
+            return false;
+        }
+
+        @Override
+        public boolean verifyGet(String filterSchema, String withDefaultsMode) {
+            return false;
+        }
+
+        @Override
+        public String buildGetReply() {
+            return null;
+        }
+
+        @Override
+        public boolean verifyWrappedRpc(String request) {
+            boolean result;
+
+            request = request.replaceAll(TEST_DUPLICATE_SPACES_REGEX, TEST_SPACE);
+            assertTrue("Does not contain:" + TEST_ONDEMAND_FWDL_WITH_NAMESPACE,
+                    request.contains(TEST_ONDEMAND_FWDL_WITH_NAMESPACE));
+
+            result = verifyWrappedRpcRequest(request);
+            assertTrue("XML verification failure", result);
+            return result;
+        }
+
+        @Override
+        public void verifyStartSubscription(String filterSchema) {
+        }
+    }
+
+}
diff --git a/drivers/fujitsu/src/test/java/org/onosproject/drivers/fujitsu/FujitsuVoltXmlUtilityMock.java b/drivers/fujitsu/src/test/java/org/onosproject/drivers/fujitsu/FujitsuVoltXmlUtilityMock.java
index 19a6981..f514883 100644
--- a/drivers/fujitsu/src/test/java/org/onosproject/drivers/fujitsu/FujitsuVoltXmlUtilityMock.java
+++ b/drivers/fujitsu/src/test/java/org/onosproject/drivers/fujitsu/FujitsuVoltXmlUtilityMock.java
@@ -60,6 +60,7 @@
     public static final int THIRD_PART = 2;
     public static final int ZERO = 0;
     public static final int ONE = 1;
+    public static final int THREE = 3;
 
     private FujitsuVoltXmlUtilityMock() {
     }