diff --git a/utils/misc/src/test/java/org/onlab/packet/dhcp/Dhcp6RelayTest.java b/utils/misc/src/test/java/org/onlab/packet/dhcp/Dhcp6RelayTest.java
new file mode 100644
index 0000000..f8a0425
--- /dev/null
+++ b/utils/misc/src/test/java/org/onlab/packet/dhcp/Dhcp6RelayTest.java
@@ -0,0 +1,586 @@
+/*
+ * Copyright 2017-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.onlab.packet.dhcp;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Lists;
+import org.apache.commons.io.IOUtils;
+import org.junit.Test;
+import org.onlab.packet.DHCP6;
+import org.onlab.packet.Ip6Address;
+import org.onlab.packet.MacAddress;
+
+import java.util.Collections;
+import java.util.List;
+
+import static org.junit.Assert.*;
+
+/**
+ * Test serializing/deserializing DHCPv6 relay message.
+ */
+public class Dhcp6RelayTest {
+    private static final String SOLICIT = "dhcp6_relay_solicit.bin";
+    private static final String ADVERTISE = "dhcp6_relay_advertise.bin";
+    private static final String REQUEST = "dhcp6_relay_request.bin";
+    private static final String REPLY = "dhcp6_relay_reply.bin";
+
+    private static final int HOP_COUNT = 0;
+    private static final Ip6Address LINK_ADDRESS = Ip6Address.valueOf("2000::2ff");
+    private static final Ip6Address PEER_ADDRESS = Ip6Address.valueOf("fe80::1");
+    private static final int XID_1 = 13346301;
+    private static final int XID_2 = 9807588;
+    private static final int IA_ID = 1;
+    private static final int T1_CLIENT = 3600;
+    private static final int T2_CLIENT = 5400;
+    private static final int T1_SERVER = 0;
+    private static final int T2_SERVER = 0;
+    private static final Ip6Address IA_ADDRESS = Ip6Address.valueOf("2000::201");
+    private static final int PREFFERRED_LT_SERVER = 375;
+    private static final int VALID_LT_SERVER = 600;
+    private static final int PREFFERRED_LT_REQ = 7200;
+    private static final int VALID_LT_REQ = 7500;
+    private static final MacAddress CLIENT_MAC = MacAddress.valueOf("00:bb:00:00:00:01");
+    private static final int CLIENT_DUID_TIME = 0x210016b4;
+
+    /**
+     * Test deserialize relay message with solicit message.
+     *
+     * @throws Exception exception while deserialize the DHCPv6 payload
+     */
+    @Test
+    public void deserializeSolicit() throws Exception {
+        byte[] data = IOUtils.toByteArray(Dhcp6RelayTest.class.getResource(SOLICIT));
+        DHCP6 relayMsg = DHCP6.deserializer().deserialize(data, 0, data.length);
+        assertEquals(relayMsg.getMsgType(), DHCP6.MsgType.RELAY_FORW.value());
+        assertEquals(relayMsg.getHopCount(), HOP_COUNT);
+        assertEquals(relayMsg.getIp6LinkAddress(), LINK_ADDRESS);
+        assertEquals(relayMsg.getIp6PeerAddress(), PEER_ADDRESS);
+
+        assertEquals(relayMsg.getOptions().size(), 1);
+        Dhcp6Option option = relayMsg.getOptions().get(0);
+        assertEquals(option.getCode(), DHCP6.OptionCode.RELAY_MSG.value());
+        assertEquals(option.getLength(), 56);
+        assertTrue(option.getPayload() instanceof DHCP6);
+
+        DHCP6 relaiedDhcp6 = (DHCP6) option.getPayload();
+        assertEquals(relaiedDhcp6.getMsgType(), DHCP6.MsgType.SOLICIT.value());
+        assertEquals(relaiedDhcp6.getTransactionId(), XID_1);
+        assertEquals(relaiedDhcp6.getOptions().size(), 4);
+
+        // Client ID
+        option = relaiedDhcp6.getOptions().get(0);
+        assertTrue(option instanceof Dhcp6ClientIdOption);
+        Dhcp6ClientIdOption clientIdOption = (Dhcp6ClientIdOption) option;
+        assertEquals(clientIdOption.getCode(), DHCP6.OptionCode.CLIENTID.value());
+        assertEquals(clientIdOption.getLength(), 14);
+        assertEquals(clientIdOption.getDuid().getDuidType(), Dhcp6Duid.DuidType.DUID_LLT);
+        assertEquals(clientIdOption.getDuid().getHardwareType(), 1);
+        assertEquals(clientIdOption.getDuid().getDuidTime(), CLIENT_DUID_TIME);
+        assertArrayEquals(clientIdOption.getDuid().getLinkLayerAddress(), CLIENT_MAC.toBytes());
+
+        // ORO
+        option = relaiedDhcp6.getOptions().get(1);
+        assertEquals(option.getCode(), DHCP6.OptionCode.ORO.value());
+        assertEquals(option.getLength(), 8);
+        assertArrayEquals(option.getData(),
+                          new byte[]{0, 23, 0, 24, 0, 39, 0, 31});
+
+        // ELAPSED_TIME
+        option = relaiedDhcp6.getOptions().get(2);
+        assertEquals(option.getCode(), DHCP6.OptionCode.ELAPSED_TIME.value());
+        assertEquals(option.getLength(), 2);
+        assertArrayEquals(option.getData(),
+                          new byte[]{0, 0});
+
+        // IA NA
+        option = relaiedDhcp6.getOptions().get(3);
+        assertTrue(option instanceof Dhcp6IaNaOption);
+        Dhcp6IaNaOption iaNaOption = (Dhcp6IaNaOption) option;
+        assertEquals(iaNaOption.getCode(), DHCP6.OptionCode.IA_NA.value());
+        assertEquals(iaNaOption.getLength(), 12);
+        assertEquals(iaNaOption.getIaId(), IA_ID);
+        assertEquals(iaNaOption.getT1(), T1_CLIENT);
+        assertEquals(iaNaOption.getT2(), T2_CLIENT);
+        assertEquals(iaNaOption.getOptions().size(), 0);
+
+        assertArrayEquals(data, relayMsg.serialize());
+    }
+
+    /**
+     * Test serialize relay message with solicit message.
+     *
+     * @throws Exception exception while serialize the DHCPv6 payload
+     */
+    @Test
+    public void serializeSolicit() throws Exception {
+        DHCP6 relayMsg = new DHCP6();
+        relayMsg.setMsgType(DHCP6.MsgType.RELAY_FORW.value());
+        relayMsg.setHopCount((byte) HOP_COUNT);
+        relayMsg.setLinkAddress(LINK_ADDRESS.toOctets());
+        relayMsg.setPeerAddress(PEER_ADDRESS.toOctets());
+
+        DHCP6 relaiedDhcp6 = new DHCP6();
+        relaiedDhcp6.setMsgType(DHCP6.MsgType.SOLICIT.value());
+        relaiedDhcp6.setTransactionId(XID_1);
+        List<Dhcp6Option> options = Lists.newArrayList();
+
+        // Client ID
+        Dhcp6Duid duid = new Dhcp6Duid();
+        duid.setDuidType(Dhcp6Duid.DuidType.DUID_LLT);
+        duid.setHardwareType((short) 1);
+        duid.setDuidTime(CLIENT_DUID_TIME);
+        duid.setLinkLayerAddress(CLIENT_MAC.toBytes());
+        Dhcp6ClientIdOption clientIdOption = new Dhcp6ClientIdOption();
+        clientIdOption.setDuid(duid);
+        options.add(clientIdOption);
+
+        // Option request
+        Dhcp6Option option = new Dhcp6Option();
+        option.setCode(DHCP6.OptionCode.ORO.value());
+        option.setLength((short) 8);
+        option.setData(new byte[]{0, 23, 0, 24, 0, 39, 0, 31});
+        options.add(option);
+
+        // Elapsed Time
+        option = new Dhcp6Option();
+        option.setCode(DHCP6.OptionCode.ELAPSED_TIME.value());
+        option.setLength((short) 2);
+        option.setData(new byte[]{0, 0});
+        options.add(option);
+
+        // IA NA
+        Dhcp6IaNaOption iaNaOption = new Dhcp6IaNaOption();
+        iaNaOption.setIaId(IA_ID);
+        iaNaOption.setT1(T1_CLIENT);
+        iaNaOption.setT2(T2_CLIENT);
+        iaNaOption.setOptions(Collections.emptyList());
+        options.add(iaNaOption);
+        relaiedDhcp6.setOptions(options);
+
+
+        Dhcp6RelayOption relayOption = new Dhcp6RelayOption();
+        relayOption.setPayload(relaiedDhcp6);
+
+        relayMsg.setOptions(ImmutableList.of(relayOption));
+        assertArrayEquals(IOUtils.toByteArray(Dhcp6RelayTest.class.getResource(SOLICIT)),
+                          relayMsg.serialize());
+    }
+
+    /**
+     * Test deserialize relay message with advertise message.
+     *
+     * @throws Exception exception while deserialize the DHCPv6 payload
+     */
+    @Test
+    public void deserializeAdvertise() throws Exception {
+        byte[] data = IOUtils.toByteArray(getClass().getResource(ADVERTISE));
+        DHCP6 relayMsg = DHCP6.deserializer().deserialize(data, 0, data.length);
+
+        assertEquals(relayMsg.getMsgType(), DHCP6.MsgType.RELAY_REPL.value());
+        assertEquals(relayMsg.getHopCount(), HOP_COUNT);
+        assertEquals(relayMsg.getIp6LinkAddress(), LINK_ADDRESS);
+        assertEquals(relayMsg.getIp6PeerAddress(), PEER_ADDRESS);
+
+        assertEquals(relayMsg.getOptions().size(), 1);
+        Dhcp6Option option = relayMsg.getOptions().get(0);
+        assertEquals(option.getCode(), DHCP6.OptionCode.RELAY_MSG.value());
+        assertEquals(option.getLength(), 84);
+        assertTrue(option.getPayload() instanceof DHCP6);
+
+        DHCP6 relaiedDhcp6 = (DHCP6) option.getPayload();
+        assertEquals(relaiedDhcp6.getMsgType(), DHCP6.MsgType.ADVERTISE.value());
+        assertEquals(relaiedDhcp6.getTransactionId(), XID_1);
+        assertEquals(relaiedDhcp6.getOptions().size(), 3);
+
+        // IA NA
+        option = relaiedDhcp6.getOptions().get(0);
+        assertTrue(option instanceof Dhcp6IaNaOption);
+        Dhcp6IaNaOption iaNaOption = (Dhcp6IaNaOption) option;
+        assertEquals(iaNaOption.getCode(), DHCP6.OptionCode.IA_NA.value());
+        assertEquals(iaNaOption.getLength(), 40);
+        assertEquals(iaNaOption.getIaId(), IA_ID);
+        assertEquals(iaNaOption.getT1(), T1_SERVER);
+        assertEquals(iaNaOption.getT2(), T2_SERVER);
+        assertEquals(iaNaOption.getOptions().size(), 1);
+
+        // IA Address (in IA NA)
+        assertTrue(iaNaOption.getOptions().get(0) instanceof Dhcp6IaAddressOption);
+        Dhcp6IaAddressOption iaAddressOption =
+                (Dhcp6IaAddressOption) iaNaOption.getOptions().get(0);
+        assertEquals(iaAddressOption.getIp6Address(), IA_ADDRESS);
+        assertEquals(iaAddressOption.getPreferredLifetime(), PREFFERRED_LT_SERVER);
+        assertEquals(iaAddressOption.getValidLifetime(), VALID_LT_SERVER);
+        assertNull(iaAddressOption.getOptions());
+
+        // Client ID
+        option = relaiedDhcp6.getOptions().get(1);
+        assertTrue(option instanceof Dhcp6ClientIdOption);
+        Dhcp6ClientIdOption clientIdOption = (Dhcp6ClientIdOption) option;
+        assertEquals(clientIdOption.getCode(), DHCP6.OptionCode.CLIENTID.value());
+        assertEquals(clientIdOption.getLength(), 14);
+        assertEquals(clientIdOption.getDuid().getDuidType(), Dhcp6Duid.DuidType.DUID_LLT);
+        assertEquals(clientIdOption.getDuid().getHardwareType(), 1);
+        assertEquals(clientIdOption.getDuid().getDuidTime(), CLIENT_DUID_TIME);
+        assertArrayEquals(clientIdOption.getDuid().getLinkLayerAddress(), CLIENT_MAC.toBytes());
+
+        // Server ID
+        option = relaiedDhcp6.getOptions().get(2);
+        assertEquals(option.getCode(), DHCP6.OptionCode.SERVERID.value());
+        assertEquals(option.getLength(), 14);
+        assertArrayEquals(option.getData(),
+                          new byte[]{0, 1, 0, 1, 32, -1, -8, -17, 0, -103, 102, 0, 0, 1});
+
+        assertArrayEquals(data, relayMsg.serialize());
+    }
+
+    /**
+     * Test serialize relay message with advertise message.
+     *
+     * @throws Exception exception while serialize the DHCPv6 payload
+     */
+    @Test
+    public void serializeAdvertise() throws Exception {
+        DHCP6 relayMsg = new DHCP6();
+        relayMsg.setMsgType(DHCP6.MsgType.RELAY_REPL.value());
+        relayMsg.setHopCount((byte) HOP_COUNT);
+        relayMsg.setLinkAddress(LINK_ADDRESS.toOctets());
+        relayMsg.setPeerAddress(PEER_ADDRESS.toOctets());
+
+        DHCP6 relaiedDhcp6 = new DHCP6();
+        relaiedDhcp6.setMsgType(DHCP6.MsgType.ADVERTISE.value());
+        relaiedDhcp6.setTransactionId(XID_1);
+        List<Dhcp6Option> options = Lists.newArrayList();
+
+        // IA address
+        Dhcp6IaAddressOption iaAddressOption = new Dhcp6IaAddressOption();
+        iaAddressOption.setIp6Address(IA_ADDRESS);
+        iaAddressOption.setPreferredLifetime(PREFFERRED_LT_SERVER);
+        iaAddressOption.setValidLifetime(VALID_LT_SERVER);
+
+        // IA NA
+        Dhcp6IaNaOption iaNaOption = new Dhcp6IaNaOption();
+        iaNaOption.setIaId(IA_ID);
+        iaNaOption.setT1(T1_SERVER);
+        iaNaOption.setT2(T2_SERVER);
+        iaNaOption.setOptions(ImmutableList.of(iaAddressOption));
+        options.add(iaNaOption);
+
+        // Client ID
+        Dhcp6Duid duid = new Dhcp6Duid();
+        duid.setDuidType(Dhcp6Duid.DuidType.DUID_LLT);
+        duid.setHardwareType((short) 1);
+        duid.setDuidTime(CLIENT_DUID_TIME);
+        duid.setLinkLayerAddress(CLIENT_MAC.toBytes());
+        Dhcp6ClientIdOption clientIdOption = new Dhcp6ClientIdOption();
+        clientIdOption.setDuid(duid);
+        options.add(clientIdOption);
+
+        // Server ID
+        Dhcp6Option option = new Dhcp6Option();
+        option.setCode(DHCP6.OptionCode.SERVERID.value());
+        option.setLength((short) 14);
+        option.setData(new byte[]{0, 1, 0, 1, 32, -1, -8, -17, 0, -103, 102, 0, 0, 1});
+        options.add(option);
+
+        relaiedDhcp6.setOptions(options);
+
+        Dhcp6RelayOption relayOption = new Dhcp6RelayOption();
+        relayOption.setPayload(relaiedDhcp6);
+
+        relayMsg.setOptions(ImmutableList.of(relayOption));
+
+        assertArrayEquals(IOUtils.toByteArray(Dhcp6RelayTest.class.getResource(ADVERTISE)),
+                          relayMsg.serialize());
+    }
+
+    /**
+     * Test deserialize relay message with request message.
+     *
+     * @throws Exception exception while deserialize the DHCPv6 payload
+     */
+    @Test
+    public void deserializeRequest() throws Exception {
+        byte[] data = IOUtils.toByteArray(getClass().getResource(REQUEST));
+        DHCP6 relayMsg = DHCP6.deserializer().deserialize(data, 0, data.length);
+
+        assertEquals(relayMsg.getMsgType(), DHCP6.MsgType.RELAY_FORW.value());
+        assertEquals(relayMsg.getHopCount(), HOP_COUNT);
+        assertEquals(relayMsg.getIp6LinkAddress(), LINK_ADDRESS);
+        assertEquals(relayMsg.getIp6PeerAddress(), PEER_ADDRESS);
+
+        assertEquals(relayMsg.getOptions().size(), 1);
+        Dhcp6Option option = relayMsg.getOptions().get(0);
+        assertEquals(option.getCode(), DHCP6.OptionCode.RELAY_MSG.value());
+        assertEquals(option.getLength(), 102);
+        assertTrue(option.getPayload() instanceof DHCP6);
+
+        DHCP6 relaiedDhcp6 = (DHCP6) option.getPayload();
+        assertEquals(relaiedDhcp6.getMsgType(), DHCP6.MsgType.REQUEST.value());
+        assertEquals(relaiedDhcp6.getTransactionId(), XID_2);
+        assertEquals(relaiedDhcp6.getOptions().size(), 5);
+
+        // Client ID
+        option = relaiedDhcp6.getOptions().get(0);
+        assertTrue(option instanceof Dhcp6ClientIdOption);
+        Dhcp6ClientIdOption clientIdOption = (Dhcp6ClientIdOption) option;
+        assertEquals(clientIdOption.getCode(), DHCP6.OptionCode.CLIENTID.value());
+        assertEquals(clientIdOption.getLength(), 14);
+        assertEquals(clientIdOption.getDuid().getDuidType(), Dhcp6Duid.DuidType.DUID_LLT);
+        assertEquals(clientIdOption.getDuid().getHardwareType(), 1);
+        assertEquals(clientIdOption.getDuid().getDuidTime(), CLIENT_DUID_TIME);
+        assertArrayEquals(clientIdOption.getDuid().getLinkLayerAddress(), CLIENT_MAC.toBytes());
+
+        // Server ID
+        option = relaiedDhcp6.getOptions().get(1);
+        assertEquals(option.getCode(), DHCP6.OptionCode.SERVERID.value());
+        assertEquals(option.getLength(), 14);
+        assertArrayEquals(option.getData(),
+                          new byte[]{0, 1, 0, 1, 32, -1, -8, -17, 0, -103, 102, 0, 0, 1});
+
+        // Option Request
+        option = relaiedDhcp6.getOptions().get(2);
+        assertEquals(option.getCode(), DHCP6.OptionCode.ORO.value());
+        assertEquals(option.getLength(), 8);
+        assertArrayEquals(option.getData(), new byte[]{0, 23, 0, 24, 0, 39, 0, 31});
+
+        // ELAPSED_TIME
+        option = relaiedDhcp6.getOptions().get(3);
+        assertEquals(option.getCode(), DHCP6.OptionCode.ELAPSED_TIME.value());
+        assertEquals(option.getLength(), 2);
+        assertArrayEquals(option.getData(),
+                          new byte[]{0, 0});
+
+        // IA NA
+        option = relaiedDhcp6.getOptions().get(4);
+        assertTrue(option instanceof Dhcp6IaNaOption);
+        Dhcp6IaNaOption iaNaOption = (Dhcp6IaNaOption) option;
+        assertEquals(iaNaOption.getCode(), DHCP6.OptionCode.IA_NA.value());
+        assertEquals(iaNaOption.getLength(), 40);
+        assertEquals(iaNaOption.getIaId(), IA_ID);
+        assertEquals(iaNaOption.getT1(), T1_CLIENT);
+        assertEquals(iaNaOption.getT2(), T2_CLIENT);
+        assertEquals(iaNaOption.getOptions().size(), 1);
+
+        // IA Address (in IA NA)
+        assertTrue(iaNaOption.getOptions().get(0) instanceof Dhcp6IaAddressOption);
+        Dhcp6IaAddressOption iaAddressOption =
+                (Dhcp6IaAddressOption) iaNaOption.getOptions().get(0);
+        assertEquals(iaAddressOption.getIp6Address(), IA_ADDRESS);
+        assertEquals(iaAddressOption.getPreferredLifetime(), PREFFERRED_LT_REQ);
+        assertEquals(iaAddressOption.getValidLifetime(), VALID_LT_REQ);
+        assertNull(iaAddressOption.getOptions());
+
+        assertArrayEquals(data, relayMsg.serialize());
+    }
+
+    /**
+     * Test serialize relay message with request message.
+     *
+     * @throws Exception exception while serialize the DHCPv6 payload
+     */
+    @Test
+    public void serializeRequest() throws Exception {
+        DHCP6 relayMsg = new DHCP6();
+        relayMsg.setMsgType(DHCP6.MsgType.RELAY_FORW.value());
+        relayMsg.setHopCount((byte) HOP_COUNT);
+        relayMsg.setLinkAddress(LINK_ADDRESS.toOctets());
+        relayMsg.setPeerAddress(PEER_ADDRESS.toOctets());
+
+        DHCP6 relaiedDhcp6 = new DHCP6();
+        relaiedDhcp6.setMsgType(DHCP6.MsgType.REQUEST.value());
+        relaiedDhcp6.setTransactionId(XID_2);
+        List<Dhcp6Option> options = Lists.newArrayList();
+
+        // Client ID
+        Dhcp6Duid duid = new Dhcp6Duid();
+        duid.setDuidType(Dhcp6Duid.DuidType.DUID_LLT);
+        duid.setHardwareType((short) 1);
+        duid.setDuidTime(CLIENT_DUID_TIME);
+        duid.setLinkLayerAddress(CLIENT_MAC.toBytes());
+        Dhcp6ClientIdOption clientIdOption = new Dhcp6ClientIdOption();
+        clientIdOption.setDuid(duid);
+        options.add(clientIdOption);
+
+        // Server ID
+        Dhcp6Option option = new Dhcp6Option();
+        option.setCode(DHCP6.OptionCode.SERVERID.value());
+        option.setLength((short) 14);
+        option.setData(new byte[]{0, 1, 0, 1, 32, -1, -8, -17, 0, -103, 102, 0, 0, 1});
+        options.add(option);
+
+        // Option request
+        option = new Dhcp6Option();
+        option.setCode(DHCP6.OptionCode.ORO.value());
+        option.setLength((short) 8);
+        option.setData(new byte[]{0, 23, 0, 24, 0, 39, 0, 31});
+        options.add(option);
+
+        // Elapsed Time
+        option = new Dhcp6Option();
+        option.setCode(DHCP6.OptionCode.ELAPSED_TIME.value());
+        option.setLength((short) 2);
+        option.setData(new byte[]{0, 0});
+        options.add(option);
+
+        // IA address
+        Dhcp6IaAddressOption iaAddressOption = new Dhcp6IaAddressOption();
+        iaAddressOption.setIp6Address(IA_ADDRESS);
+        iaAddressOption.setPreferredLifetime(PREFFERRED_LT_REQ);
+        iaAddressOption.setValidLifetime(VALID_LT_REQ);
+
+        // IA NA
+        Dhcp6IaNaOption iaNaOption = new Dhcp6IaNaOption();
+        iaNaOption.setIaId(IA_ID);
+        iaNaOption.setT1(T1_CLIENT);
+        iaNaOption.setT2(T2_CLIENT);
+        iaNaOption.setOptions(ImmutableList.of(iaAddressOption));
+        options.add(iaNaOption);
+
+        relaiedDhcp6.setOptions(options);
+
+        Dhcp6RelayOption relayOption = new Dhcp6RelayOption();
+        relayOption.setPayload(relaiedDhcp6);
+
+        relayMsg.setOptions(ImmutableList.of(relayOption));
+
+        assertArrayEquals(IOUtils.toByteArray(Dhcp6RelayTest.class.getResource(REQUEST)),
+                          relayMsg.serialize());
+    }
+
+    /**
+     * Test deserialize relay message with reply message.
+     *
+     * @throws Exception exception while deserialize the DHCPv6 payload
+     */
+    @Test
+    public void deserializeReply() throws Exception {
+        byte[] data = IOUtils.toByteArray(getClass().getResource(REPLY));
+        DHCP6 relayMsg = DHCP6.deserializer().deserialize(data, 0, data.length);
+
+        assertEquals(relayMsg.getMsgType(), DHCP6.MsgType.RELAY_REPL.value());
+        assertEquals(relayMsg.getHopCount(), HOP_COUNT);
+        assertEquals(relayMsg.getIp6LinkAddress(), LINK_ADDRESS);
+        assertEquals(relayMsg.getIp6PeerAddress(), PEER_ADDRESS);
+
+        assertEquals(relayMsg.getOptions().size(), 1);
+        Dhcp6Option option = relayMsg.getOptions().get(0);
+        assertEquals(option.getCode(), DHCP6.OptionCode.RELAY_MSG.value());
+        assertEquals(option.getLength(), 84);
+        assertTrue(option.getPayload() instanceof DHCP6);
+
+        DHCP6 relaiedDhcp6 = (DHCP6) option.getPayload();
+        assertEquals(relaiedDhcp6.getMsgType(), DHCP6.MsgType.REPLY.value());
+        assertEquals(relaiedDhcp6.getTransactionId(), XID_2);
+        assertEquals(relaiedDhcp6.getOptions().size(), 3);
+
+        // IA NA
+        option = relaiedDhcp6.getOptions().get(0);
+        assertTrue(option instanceof Dhcp6IaNaOption);
+        Dhcp6IaNaOption iaNaOption = (Dhcp6IaNaOption) option;
+        assertEquals(iaNaOption.getCode(), DHCP6.OptionCode.IA_NA.value());
+        assertEquals(iaNaOption.getLength(), 40);
+        assertEquals(iaNaOption.getIaId(), IA_ID);
+        assertEquals(iaNaOption.getT1(), T1_SERVER);
+        assertEquals(iaNaOption.getT2(), T2_SERVER);
+        assertEquals(iaNaOption.getOptions().size(), 1);
+
+        // IA Address (in IA NA)
+        assertTrue(iaNaOption.getOptions().get(0) instanceof Dhcp6IaAddressOption);
+        Dhcp6IaAddressOption iaAddressOption =
+                (Dhcp6IaAddressOption) iaNaOption.getOptions().get(0);
+        assertEquals(iaAddressOption.getIp6Address(), IA_ADDRESS);
+        assertEquals(iaAddressOption.getPreferredLifetime(), PREFFERRED_LT_SERVER);
+        assertEquals(iaAddressOption.getValidLifetime(), VALID_LT_SERVER);
+        assertNull(iaAddressOption.getOptions());
+
+        // Client ID
+        option = relaiedDhcp6.getOptions().get(1);
+        assertTrue(option instanceof Dhcp6ClientIdOption);
+        Dhcp6ClientIdOption clientIdOption = (Dhcp6ClientIdOption) option;
+        assertEquals(clientIdOption.getCode(), DHCP6.OptionCode.CLIENTID.value());
+        assertEquals(clientIdOption.getLength(), 14);
+        assertEquals(clientIdOption.getDuid().getDuidType(), Dhcp6Duid.DuidType.DUID_LLT);
+        assertEquals(clientIdOption.getDuid().getHardwareType(), 1);
+        assertEquals(clientIdOption.getDuid().getDuidTime(), CLIENT_DUID_TIME);
+        assertArrayEquals(clientIdOption.getDuid().getLinkLayerAddress(), CLIENT_MAC.toBytes());
+
+        // Server ID
+        option = relaiedDhcp6.getOptions().get(2);
+        assertEquals(option.getCode(), DHCP6.OptionCode.SERVERID.value());
+        assertEquals(option.getLength(), 14);
+        assertArrayEquals(option.getData(),
+                          new byte[]{0, 1, 0, 1, 32, -1, -8, -17, 0, -103, 102, 0, 0, 1});
+
+        assertArrayEquals(data, relayMsg.serialize());
+    }
+
+    @Test
+    public void serializeReply() throws Exception {
+        DHCP6 relayMsg = new DHCP6();
+        relayMsg.setMsgType(DHCP6.MsgType.RELAY_REPL.value());
+        relayMsg.setHopCount((byte) HOP_COUNT);
+        relayMsg.setLinkAddress(LINK_ADDRESS.toOctets());
+        relayMsg.setPeerAddress(PEER_ADDRESS.toOctets());
+
+        DHCP6 relaiedDhcp6 = new DHCP6();
+        relaiedDhcp6.setMsgType(DHCP6.MsgType.REPLY.value());
+        relaiedDhcp6.setTransactionId(XID_2);
+        List<Dhcp6Option> options = Lists.newArrayList();
+
+        // IA address
+        Dhcp6IaAddressOption iaAddressOption = new Dhcp6IaAddressOption();
+        iaAddressOption.setIp6Address(IA_ADDRESS);
+        iaAddressOption.setPreferredLifetime(PREFFERRED_LT_SERVER);
+        iaAddressOption.setValidLifetime(VALID_LT_SERVER);
+
+        // IA NA
+        Dhcp6IaNaOption iaNaOption = new Dhcp6IaNaOption();
+        iaNaOption.setIaId(IA_ID);
+        iaNaOption.setT1(T1_SERVER);
+        iaNaOption.setT2(T2_SERVER);
+        iaNaOption.setOptions(ImmutableList.of(iaAddressOption));
+        options.add(iaNaOption);
+
+        // Client ID
+        Dhcp6Duid duid = new Dhcp6Duid();
+        duid.setDuidType(Dhcp6Duid.DuidType.DUID_LLT);
+        duid.setHardwareType((short) 1);
+        duid.setDuidTime(CLIENT_DUID_TIME);
+        duid.setLinkLayerAddress(CLIENT_MAC.toBytes());
+        Dhcp6ClientIdOption clientIdOption = new Dhcp6ClientIdOption();
+        clientIdOption.setDuid(duid);
+        options.add(clientIdOption);
+
+        // Server ID
+        Dhcp6Option option = new Dhcp6Option();
+        option.setCode(DHCP6.OptionCode.SERVERID.value());
+        option.setLength((short) 14);
+        option.setData(new byte[]{0, 1, 0, 1, 32, -1, -8, -17, 0, -103, 102, 0, 0, 1});
+        options.add(option);
+
+        relaiedDhcp6.setOptions(options);
+
+        Dhcp6RelayOption relayOption = new Dhcp6RelayOption();
+        relayOption.setPayload(relaiedDhcp6);
+
+        relayMsg.setOptions(ImmutableList.of(relayOption));
+
+        assertArrayEquals(IOUtils.toByteArray(Dhcp6RelayTest.class.getResource(REPLY)),
+                          relayMsg.serialize());
+    }
+}