HC2VPP-321: bump nat model to ietf-nat@2018-02-23.yang

Uses ietf-nat module as defined in
https://tools.ietf.org/html/draft-ietf-opsawg-nat-yang-14

Modifications to original model:
- ip-address is used instead of ip-prefix
 (draft is not clear, see HC2VPP-325).

API changes relevant to HC/VPP:
- nat-config and nat-state merged into nat container
- nat-instances and nat-instace renamed
  to instances and instance respectively
- external-ip-address-pool has new parent - policy list
- port-type choice was removed, port is now defined using
  start-port-number and end-port-number leaves.
  Missing end is equivalent to single-port-number case from
  the older version.

TODOs:
- HC2VPP-322: single nat64Prefix per NAT instance
- HC2VPP-323: update postman collection
- HC2VPP-324: update CSIT tests.

Out of the scope of NAT model update:
- HC2VPP-326: support for nat-type handling
  (vpp-nat model might become obsolete)
- HC2VPP-327: support external-realm container
  (requires adding augmentations
  that are alredy present in the interface-nat model).

Change-Id: Ie229a55b0a3f6ee3f8c97f4fd13c54a797a62438
Signed-off-by: Marek Gradzki <mgradzki@cisco.com>

13 files changed, 279 insertions, 258 deletions

diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/NatIds.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/NatIds.java
new file mode 100644
index 000000000..c0aa538d5
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/NatIds.java
@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ *
+ * 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 io.fd.hc2vpp.nat;
+
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.Nat;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.Instances;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.Instance;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.MappingTable;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.Policy;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.ExternalIpAddressPool;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.Nat64Prefixes;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+public interface NatIds {
+    InstanceIdentifier<Nat> NAT_ID = InstanceIdentifier.create(Nat.class);
+    InstanceIdentifier<Instances> NAT_INSTANCES_ID = NAT_ID.child(Instances.class);
+    InstanceIdentifier<Instance> NAT_INSTANCE_ID = NAT_INSTANCES_ID.child(Instance.class);
+    InstanceIdentifier<MappingTable> MAPPING_TABLE_ID = NAT_INSTANCE_ID.child(MappingTable.class);
+    InstanceIdentifier<MappingEntry> MAPPING_ENTRY_ID = MAPPING_TABLE_ID.child(MappingEntry.class);
+    InstanceIdentifier<Policy> POLICY_ID = NAT_INSTANCE_ID.child(Policy.class);
+    InstanceIdentifier<ExternalIpAddressPool> ADDRESS_POOL_ID = POLICY_ID.child(ExternalIpAddressPool.class);
+    InstanceIdentifier<Nat64Prefixes> NAT64_PREFIXES_ID = POLICY_ID.child(Nat64Prefixes.class);
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/ExternalIpPoolCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/ExternalIpPoolCustomizer.java
index 77b5b2cf6..cfc9be4ce 100644
--- a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/ExternalIpPoolCustomizer.java
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/ExternalIpPoolCustomizer.java
@@ -24,7 +24,6 @@ import io.fd.honeycomb.translate.read.ReadContext;
 import io.fd.honeycomb.translate.read.ReadFailedException;
 import io.fd.honeycomb.translate.spi.read.Initialized;
 import io.fd.honeycomb.translate.spi.read.InitializingListReaderCustomizer;
-import io.fd.honeycomb.translate.util.RWUtils;
 import io.fd.honeycomb.translate.util.read.cache.DumpCacheManager;
 import io.fd.vpp.jvpp.nat.dto.Nat44AddressDetails;
 import io.fd.vpp.jvpp.nat.dto.Nat44AddressDetailsReplyDump;
@@ -39,15 +38,15 @@ import java.util.stream.Collectors;
 import java.util.stream.LongStream;
 import javax.annotation.Nonnull;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Ipv4Prefix;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.ExternalIpAddressPool;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.ExternalIpAddressPoolBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.ExternalIpAddressPoolKey;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.NatInstance;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.NatInstanceKey;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.nat.instance.NatCurrentConfigBuilder;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev170804.ExternalIpAddressPoolStateAugmentation;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev170804.ExternalIpAddressPoolStateAugmentationBuilder;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev170804.NatPoolType;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.Instance;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.InstanceKey;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.PolicyBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.ExternalIpAddressPool;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.ExternalIpAddressPoolBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.ExternalIpAddressPoolKey;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev180510.ExternalIpAddressPoolAugmentation;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev180510.ExternalIpAddressPoolAugmentationBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev180510.NatPoolType;
 import org.opendaylight.yangtools.concepts.Builder;
 import org.opendaylight.yangtools.yang.binding.DataObject;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
@@ -76,13 +75,8 @@ final class ExternalIpPoolCustomizer implements
     }
 
     private static void setPoolType(@Nonnull final ExternalIpAddressPoolBuilder builder, final NatPoolType poolType) {
-        builder.addAugmentation(ExternalIpAddressPoolStateAugmentation.class,
-                new ExternalIpAddressPoolStateAugmentationBuilder().setPoolType(poolType).build());
-    }
-
-    static InstanceIdentifier<ExternalIpAddressPool> getCfgId(final @Nonnull InstanceIdentifier<ExternalIpAddressPool> id) {
-        return NatInstanceCustomizer.getCfgId(RWUtils.cutId(id, NatInstance.class))
-                .child(ExternalIpAddressPool.class, id.firstKeyOf(ExternalIpAddressPool.class));
+        builder.addAugmentation(ExternalIpAddressPoolAugmentation.class,
+                new ExternalIpAddressPoolAugmentationBuilder().setPoolType(poolType).build());
     }
 
     @Nonnull
@@ -138,7 +132,7 @@ final class ExternalIpPoolCustomizer implements
     @Override
     public List<ExternalIpAddressPoolKey> getAllIds(@Nonnull final InstanceIdentifier<ExternalIpAddressPool> id,
                                                     @Nonnull final ReadContext ctx) throws ReadFailedException {
-        final NatInstanceKey natKey = id.firstKeyOf(NatInstance.class);
+        final InstanceKey natKey = id.firstKeyOf(Instance.class);
         if (!natKey.equals(NatInstanceCustomizer.DEFAULT_VRF_ID)) {
             // IP Pools are not vrf aware ... so they are only visible under default vrf (nat-instance)
             return Collections.emptyList();
@@ -174,7 +168,7 @@ final class ExternalIpPoolCustomizer implements
     @Override
     public void merge(@Nonnull final Builder<? extends DataObject> builder,
                       @Nonnull final List<ExternalIpAddressPool> readData) {
-        ((NatCurrentConfigBuilder) builder).setExternalIpAddressPool(readData);
+        ((PolicyBuilder) builder).setExternalIpAddressPool(readData);
     }
 
     @Override
@@ -182,6 +176,6 @@ final class ExternalIpPoolCustomizer implements
             @Nonnull final InstanceIdentifier<ExternalIpAddressPool> id,
             @Nonnull final ExternalIpAddressPool readValue,
             @Nonnull final ReadContext ctx) {
-        return Initialized.create(getCfgId(id), readValue);
+        return Initialized.create(id, readValue);
     }
 }
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/MappingEntryCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/MappingEntryCustomizer.java
index 9075f4d0c..43dba092a 100644
--- a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/MappingEntryCustomizer.java
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/MappingEntryCustomizer.java
@@ -24,7 +24,6 @@ import io.fd.honeycomb.translate.read.ReadContext;
 import io.fd.honeycomb.translate.read.ReadFailedException;
 import io.fd.honeycomb.translate.spi.read.Initialized;
 import io.fd.honeycomb.translate.spi.read.InitializingListReaderCustomizer;
-import io.fd.honeycomb.translate.util.RWUtils;
 import io.fd.honeycomb.translate.util.read.cache.DumpCacheManager;
 import io.fd.honeycomb.translate.util.read.cache.EntityDumpExecutor;
 import io.fd.vpp.jvpp.nat.dto.Nat44StaticMappingDetails;
@@ -40,15 +39,13 @@ import java.util.stream.Collectors;
 import javax.annotation.Nonnull;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.IpAddress;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.PortNumber;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.mapping.entry.ExternalSrcPortBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.mapping.entry.InternalSrcPortBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.MappingTable;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.NatInstance;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.nat.instance.MappingTableBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.nat.instance.mapping.table.MappingEntry;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.nat.instance.mapping.table.MappingEntryBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.nat.instance.mapping.table.MappingEntryKey;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.port.number.port.type.SinglePortNumberBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.mapping.entry.ExternalSrcPortBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.mapping.entry.InternalSrcPortBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.Instance;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.MappingTableBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntryBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntryKey;
 import org.opendaylight.yangtools.concepts.Builder;
 import org.opendaylight.yangtools.yang.binding.DataObject;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
@@ -56,7 +53,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 final class MappingEntryCustomizer implements Ipv4Translator, Ipv6Translator,
-        InitializingListReaderCustomizer<MappingEntry, MappingEntryKey, MappingEntryBuilder> {
+    InitializingListReaderCustomizer<MappingEntry, MappingEntryKey, MappingEntryBuilder> {
 
     private static final Logger LOG = LoggerFactory.getLogger(MappingEntryCustomizer.class);
 
@@ -86,7 +83,7 @@ final class MappingEntryCustomizer implements Ipv4Translator, Ipv6Translator,
         LOG.trace("Reading current attributes for mapping-entry: {}", id);
 
         final int idx = id.firstKeyOf(MappingEntry.class).getIndex().intValue();
-        final int natInstanceId = id.firstKeyOf(NatInstance.class).getId().intValue();
+        final int natInstanceId = id.firstKeyOf(Instance.class).getId().intValue();
         final List<Nat44StaticMappingDetails> nat44Details =
                 nat44DumpManager.getDump(id, ctx.getModificationCache())
                         .or(new Nat44StaticMappingDetailsReplyDump()).nat44StaticMappingDetails;
@@ -116,22 +113,16 @@ final class MappingEntryCustomizer implements Ipv4Translator, Ipv6Translator,
                                 final int index, final Nat44StaticMappingDetails detail) {
         builder.setIndex((long) index);
         builder.setType(
-                org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.MappingEntry.Type.Static);
+                org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.MappingEntry.Type.Static);
         builder.setExternalSrcAddress(arrayToIpv4AddressNoZone(detail.externalIpAddress));
         builder.setInternalSrcAddress(
                 new IpAddress(arrayToIpv4AddressNoZone(detail.localIpAddress)));
 
         if (detail.addrOnly == 0) {
             builder.setExternalSrcPort(new ExternalSrcPortBuilder()
-                    .setPortType(new SinglePortNumberBuilder().setSinglePortNumber(new PortNumber(
-                            Short.toUnsignedInt(detail.externalPort)))
-                            .build())
-                    .build());
+                .setStartPortNumber(new PortNumber(Short.toUnsignedInt(detail.externalPort))).build());
             builder.setInternalSrcPort(new InternalSrcPortBuilder()
-                    .setPortType(new SinglePortNumberBuilder().setSinglePortNumber(new PortNumber(
-                            Short.toUnsignedInt(detail.localPort)))
-                            .build())
-                    .build());
+                .setStartPortNumber(new PortNumber(Short.toUnsignedInt(detail.localPort))).build());
         }
     }
 
@@ -140,32 +131,26 @@ final class MappingEntryCustomizer implements Ipv4Translator, Ipv6Translator,
         builder.setIndex((long) index);
         if (detail.isStatic == 1) {
             builder.setType(
-                    org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.MappingEntry.Type.Static);
+                    org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.MappingEntry.Type.Static);
         } else {
             builder.setType(
-                    org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.MappingEntry.Type.Dynamic);
+                    org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.MappingEntry.Type.DynamicImplicit);
         }
         builder.setExternalSrcAddress(arrayToIpv4AddressNoZone(detail.oAddr));
         builder.setInternalSrcAddress(
                 new IpAddress(arrayToIpv6AddressNoZone(detail.iAddr)));
 
         builder.setExternalSrcPort(new ExternalSrcPortBuilder()
-                .setPortType(new SinglePortNumberBuilder().setSinglePortNumber(new PortNumber(
-                        Short.toUnsignedInt(detail.oPort)))
-                        .build())
-                .build());
+            .setStartPortNumber(new PortNumber(Short.toUnsignedInt(detail.oPort))).build());
         builder.setInternalSrcPort(new InternalSrcPortBuilder()
-                .setPortType(new SinglePortNumberBuilder().setSinglePortNumber(new PortNumber(
-                        Short.toUnsignedInt(detail.iPort)))
-                        .build())
-                .build());
+            .setStartPortNumber(new PortNumber(Short.toUnsignedInt(detail.iPort))).build());
     }
 
     @Nonnull
     @Override
     public List<MappingEntryKey> getAllIds(@Nonnull final InstanceIdentifier<MappingEntry> id,
                                            @Nonnull final ReadContext context) throws ReadFailedException {
-        final Long natInstanceId = id.firstKeyOf(NatInstance.class).getId();
+        final Long natInstanceId = id.firstKeyOf(Instance.class).getId();
         LOG.trace("Listing IDs for all mapping-entries within nat-instance(vrf):{}", natInstanceId);
 
         final List<MappingEntryKey> entryKeys =
@@ -199,23 +184,11 @@ final class MappingEntryCustomizer implements Ipv4Translator, Ipv6Translator,
     }
 
     @Override
-    public Initialized<org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntry> init(
+    public Initialized<org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry> init(
             @Nonnull final InstanceIdentifier<MappingEntry> id,
             @Nonnull final MappingEntry readValue,
             @Nonnull final ReadContext ctx) {
-        return Initialized.create(getCfgId(id),
-                new org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntryBuilder(
-                        readValue)
-                        .build());
-    }
-
-    static InstanceIdentifier<org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntry> getCfgId(
-            final @Nonnull InstanceIdentifier<MappingEntry> id) {
-        return NatInstanceCustomizer.getCfgId(RWUtils.cutId(id, NatInstance.class))
-                .child(MappingTable.class)
-                .child(org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntry.class,
-                        new org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntryKey(
-                                id.firstKeyOf(MappingEntry.class).getIndex()));
+        return Initialized.create(id, readValue);
     }
 
     static final class MappingEntryNat44DumpExecutor
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/Nat64PrefixesCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/Nat64PrefixesCustomizer.java
index 5026a0127..c32bbd5a7 100644
--- a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/Nat64PrefixesCustomizer.java
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/Nat64PrefixesCustomizer.java
@@ -37,12 +37,13 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import javax.annotation.Nonnull;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.Nat64Prefixes;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.Nat64PrefixesBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.Nat64PrefixesKey;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.NatInstance;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.NatInstanceKey;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.nat.instance.NatCurrentConfigBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Ipv6Prefix;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.Instance;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.InstanceKey;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.PolicyBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.Nat64Prefixes;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.Nat64PrefixesBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.Nat64PrefixesKey;
 import org.opendaylight.yangtools.concepts.Builder;
 import org.opendaylight.yangtools.yang.binding.DataObject;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
@@ -70,16 +71,15 @@ final class Nat64PrefixesCustomizer
     public List<Nat64PrefixesKey> getAllIds(@Nonnull final InstanceIdentifier<Nat64Prefixes> id,
                                             @Nonnull final ReadContext context)
             throws ReadFailedException {
-        final NatInstanceKey natKey = id.firstKeyOf(NatInstance.class);
+        final InstanceKey natKey = id.firstKeyOf(Instance.class);
         LOG.trace("Listing IDs for all nat64 prefixes within nat-instance(vrf): {}", natKey);
 
+        // VPP supports only single nat64-prefix per VRF/nat-instance (we map nat-instances to VRFs)
         final Map<Long, Nat64PrefixDetails> prefixesByVrfId =
                 dumpManager.getDump(id, context.getModificationCache()).get();
-        final Nat64PrefixDetails nat64PrefixDetails = prefixesByVrfId.get(natKey.getId());
-        if (nat64PrefixDetails != null) {
-            // VPP supports only single nat64-prefix per VRF/nat-instance (we map nat-instances to VRFs)
-            // To ensure that (and for simplicity), we set nat64-prefix-id to 0.
-            return Collections.singletonList(new Nat64PrefixesKey(0L));
+        final Nat64PrefixDetails details = prefixesByVrfId.get(natKey.getId());
+        if (details != null) {
+            return Collections.singletonList(new Nat64PrefixesKey(readPrefix(details)));
         } else {
             return Collections.emptyList();
         }
@@ -88,7 +88,7 @@ final class Nat64PrefixesCustomizer
     @Override
     public void merge(@Nonnull final Builder<? extends DataObject> builder,
                       @Nonnull final List<Nat64Prefixes> readData) {
-        ((NatCurrentConfigBuilder) builder).setNat64Prefixes(readData);
+        ((PolicyBuilder) builder).setNat64Prefixes(readData);
     }
 
     @Nonnull
@@ -102,21 +102,18 @@ final class Nat64PrefixesCustomizer
                                       @Nonnull final Nat64PrefixesBuilder builder, @Nonnull final ReadContext context)
             throws ReadFailedException {
         LOG.trace("Reading nat64-prefixes: {}", id);
-        final long prefixId = id.firstKeyOf(Nat64Prefixes.class).getNat64PrefixId().longValue();
-        if (prefixId != 0L) {
-            // Ignore non zero IDs (VPP supports single nat64 prefix per VRF)
-            return;
-        }
         final Map<Long, Nat64PrefixDetails> prefixesByVrfId =
                 dumpManager.getDump(id, context.getModificationCache()).get();
-        final Nat64PrefixDetails prefixDetails = prefixesByVrfId.get(id.firstKeyOf(NatInstance.class).getId());
-        if (prefixDetails != null) {
-            builder.setNat64PrefixId(prefixId);
-            builder.setNat64Prefix(
-                    toIpv6Prefix(prefixDetails.prefix, UnsignedBytes.toInt(prefixDetails.prefixLen)));
+        final Nat64PrefixDetails details = prefixesByVrfId.get(id.firstKeyOf(Instance.class).getId());
+        if (details != null) {
+            builder.setNat64Prefix(readPrefix(details));
         }
     }
 
+    private Ipv6Prefix readPrefix(final Nat64PrefixDetails details) {
+        return toIpv6Prefix(details.prefix, UnsignedBytes.toInt(details.prefixLen));
+    }
+
     private final class Nat64PrefixesExecutor implements EntityDumpExecutor<Map<Long, Nat64PrefixDetails>, Void> {
         private final FutureJVppNatFacade jvppNat;
 
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/NatInstanceCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/NatInstanceCustomizer.java
index 926c6e95f..1bbd5f19e 100644
--- a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/NatInstanceCustomizer.java
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/NatInstanceCustomizer.java
@@ -27,11 +27,10 @@ import java.util.List;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 import javax.annotation.Nonnull;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.NatConfig;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.NatInstancesBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.NatInstance;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.NatInstanceBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.NatInstanceKey;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.InstancesBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.Instance;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.InstanceBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.InstanceKey;
 import org.opendaylight.yangtools.concepts.Builder;
 import org.opendaylight.yangtools.yang.binding.DataObject;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
@@ -42,10 +41,10 @@ import org.slf4j.LoggerFactory;
  * Nat instance ID is mapped to VRF-ID in VPP.
  */
 final class NatInstanceCustomizer
-        implements InitializingListReaderCustomizer<NatInstance, NatInstanceKey, NatInstanceBuilder> {
+        implements InitializingListReaderCustomizer<Instance, InstanceKey, InstanceBuilder> {
 
     private static final Logger LOG = LoggerFactory.getLogger(NatInstanceCustomizer.class);
-    static final NatInstanceKey DEFAULT_VRF_ID = new NatInstanceKey(0L);
+    static final InstanceKey DEFAULT_VRF_ID = new InstanceKey(0L);
 
     private final DumpCacheManager<Nat44StaticMappingDetailsReplyDump, Void> nat44DumpManager;
     private final DumpCacheManager<Nat64BibDetailsReplyDump, Void> nat64DumpManager;
@@ -59,26 +58,26 @@ final class NatInstanceCustomizer
 
     @Nonnull
     @Override
-    public NatInstanceBuilder getBuilder(@Nonnull final InstanceIdentifier<NatInstance> id) {
-        return new NatInstanceBuilder();
+    public InstanceBuilder getBuilder(@Nonnull final InstanceIdentifier<Instance> id) {
+        return new InstanceBuilder();
     }
 
     @Override
-    public void readCurrentAttributes(@Nonnull final InstanceIdentifier<NatInstance> id,
-                                      @Nonnull final NatInstanceBuilder builder, @Nonnull final ReadContext ctx)
+    public void readCurrentAttributes(@Nonnull final InstanceIdentifier<Instance> id,
+                                      @Nonnull final InstanceBuilder builder, @Nonnull final ReadContext ctx)
             throws ReadFailedException {
         LOG.trace("Reading current attributes for nat-instance: {}", id);
-        builder.setId(id.firstKeyOf(NatInstance.class).getId());
+        builder.setId(id.firstKeyOf(Instance.class).getId());
     }
 
     @Nonnull
     @Override
-    public List<NatInstanceKey> getAllIds(@Nonnull final InstanceIdentifier<NatInstance> id,
+    public List<InstanceKey> getAllIds(@Nonnull final InstanceIdentifier<Instance> id,
                                           @Nonnull final ReadContext context) throws ReadFailedException {
         LOG.trace("Listing IDs for all nat-instances");
 
         // Find the nat instance IDs (vrf-ids) by listing all static mappings and their VRF assignment
-        final List<NatInstanceKey> vrfIds = Stream.concat(
+        final List<InstanceKey> vrfIds = Stream.concat(
                 nat44DumpManager.getDump(id, context.getModificationCache())
                         .or(new Nat44StaticMappingDetailsReplyDump()).nat44StaticMappingDetails.stream()
                         .map(detail -> detail.vrfId),
@@ -88,7 +87,7 @@ final class NatInstanceCustomizer
                 // V4 (nat44) and V6 (nat64) VRFs in VPP can have the same id. We store them under single nat instance,
                 // because the ietf-nat model does not require separate instances for nat44 and nat64 features.
                 .distinct()
-                .map(vrfId -> new NatInstanceKey((long) vrfId))
+                .map(vrfId -> new InstanceKey((long) vrfId))
                 .collect(Collectors.toList());
 
         // Add default vrf id if not present
@@ -101,27 +100,15 @@ final class NatInstanceCustomizer
     }
 
     @Override
-    public void merge(@Nonnull final Builder<? extends DataObject> builder, @Nonnull final List<NatInstance> readData) {
-        ((NatInstancesBuilder) builder).setNatInstance(readData);
+    public void merge(@Nonnull final Builder<? extends DataObject> builder, @Nonnull final List<Instance> readData) {
+        ((InstancesBuilder) builder).setInstance(readData);
     }
 
     @Override
-    public Initialized<org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstance> init(
-            @Nonnull final InstanceIdentifier<NatInstance> id,
-            @Nonnull final NatInstance readValue,
+    public Initialized<Instance> init(
+            @Nonnull final InstanceIdentifier<Instance> id,
+            @Nonnull final Instance readValue,
             @Nonnull final ReadContext ctx) {
-        return Initialized.create(getCfgId(id),
-                new org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstanceBuilder()
-                        .setId(readValue.getId())
-                        .build());
-    }
-
-    static InstanceIdentifier<org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstance> getCfgId(
-            @Nonnull final InstanceIdentifier<NatInstance> id) {
-        return InstanceIdentifier.create(NatConfig.class)
-                .child(org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.NatInstances.class)
-                .child(org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstance.class,
-                        new org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstanceKey(
-                                id.firstKeyOf(NatInstance.class).getId()));
+        return Initialized.create(id, readValue);
     }
 }
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/NatReaderFactory.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/NatReaderFactory.java
index a97d47a1a..c89b3030f 100644
--- a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/NatReaderFactory.java
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/read/NatReaderFactory.java
@@ -16,6 +16,15 @@
 
 package io.fd.hc2vpp.nat.read;
 
+import static io.fd.hc2vpp.nat.NatIds.ADDRESS_POOL_ID;
+import static io.fd.hc2vpp.nat.NatIds.MAPPING_ENTRY_ID;
+import static io.fd.hc2vpp.nat.NatIds.MAPPING_TABLE_ID;
+import static io.fd.hc2vpp.nat.NatIds.NAT64_PREFIXES_ID;
+import static io.fd.hc2vpp.nat.NatIds.NAT_ID;
+import static io.fd.hc2vpp.nat.NatIds.NAT_INSTANCES_ID;
+import static io.fd.hc2vpp.nat.NatIds.NAT_INSTANCE_ID;
+import static io.fd.hc2vpp.nat.NatIds.POLICY_ID;
+
 import com.google.common.collect.Sets;
 import com.google.inject.Inject;
 import io.fd.hc2vpp.nat.util.MappingEntryContext;
@@ -27,40 +36,27 @@ import io.fd.honeycomb.translate.util.read.cache.DumpCacheManager;
 import io.fd.vpp.jvpp.nat.dto.Nat44StaticMappingDetailsReplyDump;
 import io.fd.vpp.jvpp.nat.dto.Nat64BibDetailsReplyDump;
 import io.fd.vpp.jvpp.nat.future.FutureJVppNatFacade;
+import java.util.Collections;
 import javax.annotation.Nonnull;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.NatState;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.NatStateBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.mapping.entry.ExternalSrcPort;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.mapping.entry.InternalSrcPort;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.ExternalIpAddressPool;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.Nat64Prefixes;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.nat64.prefixes.DestinationIpv4Prefix;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.NatInstances;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.NatInstancesBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.NatInstance;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.nat.instance.MappingTable;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.nat.instance.MappingTableBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.nat.instance.NatCurrentConfig;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.nat.instance.NatCurrentConfigBuilder;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.state.nat.instances.nat.instance.mapping.table.MappingEntry;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.NatBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.mapping.entry.ExternalSrcPort;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.mapping.entry.InternalSrcPort;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.InstancesBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.MappingTableBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.PolicyBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.PolicyKey;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.Nat64Prefixes;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.nat64.prefixes.DestinationIpv4Prefix;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
 
 public class NatReaderFactory implements ReaderFactory {
 
-    private static final InstanceIdentifier<NatState> NAT_OPER_ID = InstanceIdentifier.create(NatState.class);
-    private static final InstanceIdentifier<NatInstances> NAT_INSTANCES_ID = NAT_OPER_ID.child(NatInstances.class);
-    private static final InstanceIdentifier<NatInstance> NAT_INSTANCE_ID = NAT_INSTANCES_ID.child(NatInstance.class);
-    private static final InstanceIdentifier<NatCurrentConfig> CURRENT_CONFIG =
-            NAT_INSTANCE_ID.child(NatCurrentConfig.class);
-    private static final InstanceIdentifier<MappingTable> MAP_TABLE_ID = NAT_INSTANCE_ID.child(MappingTable.class);
-    private static final InstanceIdentifier<MappingEntry> MAP_ENTRY_ID = MAP_TABLE_ID.child(MappingEntry.class);
-
     private final FutureJVppNatFacade jvppNat;
     private final MappingEntryContext mappingEntryContext;
     private final DumpCacheManager<Nat44StaticMappingDetailsReplyDump, Void> mapEntryNat44DumpMgr;
     private final DumpCacheManager<Nat64BibDetailsReplyDump, Void> mapEntryNat64DumpMgr;
 
-
     @Inject
     public NatReaderFactory(final FutureJVppNatFacade jvppNat,
                             final MappingEntryContext mappingEntryContext) {
@@ -80,24 +76,23 @@ public class NatReaderFactory implements ReaderFactory {
 
     @Override
     public void init(@Nonnull final ModifiableReaderRegistryBuilder registry) {
-        registry.addStructuralReader(NAT_OPER_ID, NatStateBuilder.class);
-        registry.addStructuralReader(NAT_INSTANCES_ID, NatInstancesBuilder.class);
+        registry.addStructuralReader(NAT_ID, NatBuilder.class);
+        registry.addStructuralReader(NAT_INSTANCES_ID, InstancesBuilder.class);
         registry.add(new GenericInitListReader<>(NAT_INSTANCE_ID,
                 new NatInstanceCustomizer(mapEntryNat44DumpMgr, mapEntryNat64DumpMgr)));
-        registry.addStructuralReader(MAP_TABLE_ID, MappingTableBuilder.class);
+        registry.addStructuralReader(MAPPING_TABLE_ID, MappingTableBuilder.class);
         registry.subtreeAdd(Sets.newHashSet(InstanceIdentifier.create(MappingEntry.class).child(ExternalSrcPort.class),
                 InstanceIdentifier.create(MappingEntry.class).child(InternalSrcPort.class)),
-                new GenericInitListReader<>(MAP_ENTRY_ID,
+                new GenericInitListReader<>(MAPPING_ENTRY_ID,
                         new MappingEntryCustomizer(mapEntryNat44DumpMgr, mapEntryNat64DumpMgr, mappingEntryContext)));
 
-        registry.addStructuralReader(CURRENT_CONFIG, NatCurrentConfigBuilder.class);
-        registry.add(new GenericInitListReader<>(CURRENT_CONFIG.child(ExternalIpAddressPool.class),
-                new ExternalIpPoolCustomizer(jvppNat)));
+        // Ony single policy is supported
+        registry.addStructuralListReader(POLICY_ID, PolicyBuilder.class, Collections.singletonList(new PolicyKey(0L)));
+        registry.add(new GenericInitListReader<>(ADDRESS_POOL_ID, new ExternalIpPoolCustomizer(jvppNat)));
 
         // nat64-prefixes
         registry.subtreeAdd(
                 Sets.newHashSet(InstanceIdentifier.create(Nat64Prefixes.class).child(DestinationIpv4Prefix.class)),
-                new GenericListReader<>(CURRENT_CONFIG.child(Nat64Prefixes.class),
-                        new Nat64PrefixesCustomizer(jvppNat)));
+                new GenericListReader<>(NAT64_PREFIXES_ID, new Nat64PrefixesCustomizer(jvppNat)));
     }
 }
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/util/MappingEntryContext.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/util/MappingEntryContext.java
index 0f3924ec6..0f7220988 100644
--- a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/util/MappingEntryContext.java
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/util/MappingEntryContext.java
@@ -59,7 +59,7 @@ public class MappingEntryContext implements Ipv4Translator, Ipv6Translator {
      */
     public synchronized void addEntry(final long natInstanceId,
                                       final long entryId,
-                                      @Nonnull final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntry entry,
+                                      @Nonnull final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry entry,
                                       @Nonnull final MappingContext mappingContext) {
         final InstanceIdentifier<MappingEntry> id = getId(natInstanceId, entryToKey(entry));
         checkArgument(!containsEntry(natInstanceId, entry, mappingContext), "Mapping for %s already present", id);
@@ -70,7 +70,7 @@ public class MappingEntryContext implements Ipv4Translator, Ipv6Translator {
      * Check whether mapping entry to index mapping already exists in context.
      */
     public synchronized boolean containsEntry(final long natInstanceId,
-                                              @Nonnull final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntry entry,
+                                              @Nonnull final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry entry,
                                               @Nonnull final MappingContext mappingContext) {
         final InstanceIdentifier<MappingEntry> id = getId(natInstanceId, entryToKey(entry));
         return mappingContext.read(id).isPresent();
@@ -92,7 +92,7 @@ public class MappingEntryContext implements Ipv4Translator, Ipv6Translator {
 
     @VisibleForTesting
     static MappingEntryKey entryToKey(
-            final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntry entry) {
+            final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry entry) {
         // Only IPv4
         return new MappingEntryKey(new IpAddress(entry.getExternalSrcAddress()), entry.getInternalSrcAddress());
     }
@@ -144,7 +144,7 @@ public class MappingEntryContext implements Ipv4Translator, Ipv6Translator {
 
     @VisibleForTesting
     static MappingEntry toCtxMapEntry(
-            @Nonnull final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntry entry,
+            @Nonnull final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry entry,
             final long entryId) {
         return new MappingEntryBuilder()
                 .setKey(entryToKey(entry))
@@ -170,7 +170,7 @@ public class MappingEntryContext implements Ipv4Translator, Ipv6Translator {
      * Delete mapping of mapping entry to index from context.
      */
     public synchronized void removeEntry(final long natInstanceId,
-                                         @Nonnull final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntry entry,
+                                         @Nonnull final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry entry,
                                          @Nonnull final MappingContext mappingContext) {
         mappingContext.delete(getId(natInstanceId, entryToKey(entry)));
     }
@@ -245,7 +245,7 @@ public class MappingEntryContext implements Ipv4Translator, Ipv6Translator {
      * Get index for a stored mapping entry.
      */
     public synchronized Optional<Long> getStoredIndex(final long natInstanceId,
-                                                      @Nonnull final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntry entry,
+                                                      @Nonnull final org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry entry,
                                                       @Nonnull final MappingContext mappingContext) {
         return mappingContext.read(getId(natInstanceId, entryToKey(entry)))
                 .transform(MappingEntry::getIndex);
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/ExternalIpPoolCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/ExternalIpPoolCustomizer.java
index 775c9a6dd..36440b013 100644
--- a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/ExternalIpPoolCustomizer.java
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/ExternalIpPoolCustomizer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Copyright (c) 2018 Cisco and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,7 +17,7 @@
 package io.fd.hc2vpp.nat.write;
 
 import static com.google.common.base.Preconditions.checkArgument;
-import static org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev170804.NatPoolType.Nat64;
+import static org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev180510.NatPoolType.Nat64;
 
 import io.fd.hc2vpp.common.translate.util.ByteDataTranslator;
 import io.fd.hc2vpp.common.translate.util.Ipv4AddressRange;
@@ -31,10 +31,10 @@ import io.fd.vpp.jvpp.nat.dto.Nat64AddDelPoolAddrRange;
 import io.fd.vpp.jvpp.nat.future.FutureJVppNatFacade;
 import javax.annotation.Nonnull;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Ipv4Prefix;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstance;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.ExternalIpAddressPool;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.ExternalIpAddressPoolKey;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev170804.ExternalIpAddressPoolConfigAugmentation;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.Instance;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.ExternalIpAddressPool;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.ExternalIpAddressPoolKey;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev180510.ExternalIpAddressPoolAugmentation;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -54,7 +54,7 @@ final class ExternalIpPoolCustomizer implements ListWriterCustomizer<ExternalIpA
     public void writeCurrentAttributes(@Nonnull final InstanceIdentifier<ExternalIpAddressPool> id,
                                        @Nonnull final ExternalIpAddressPool dataAfter,
                                        @Nonnull final WriteContext writeContext) throws WriteFailedException {
-        checkArgument(id.firstKeyOf(NatInstance.class).getId() == 0,
+        checkArgument(id.firstKeyOf(Instance.class).getId() == 0,
                 "External IP pools are only assignable for nat instance(vrf-id) with ID 0");
         LOG.trace("Adding address range:{}, as: {}", id, dataAfter);
         // TODO check overlaps ? VPP-478 maybe no necessary, depending on how VPP handles them
@@ -75,8 +75,8 @@ final class ExternalIpPoolCustomizer implements ListWriterCustomizer<ExternalIpA
                                       @Nonnull final ExternalIpAddressPool addressPool,
                                       final boolean isAdd) throws WriteFailedException {
         boolean isNat64 = false;
-        final ExternalIpAddressPoolConfigAugmentation augmentation =
-                addressPool.getAugmentation(ExternalIpAddressPoolConfigAugmentation.class);
+        final ExternalIpAddressPoolAugmentation augmentation =
+                addressPool.getAugmentation(ExternalIpAddressPoolAugmentation.class);
         if (augmentation != null) {
             isNat64 = Nat64.equals(augmentation.getPoolType());
         }
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/MappingEntryCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/MappingEntryCustomizer.java
index 97a41c0ca..6aca1af9e 100644
--- a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/MappingEntryCustomizer.java
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/MappingEntryCustomizer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016 Cisco and/or its affiliates.
+ * Copyright (c) 2018 Cisco and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -35,12 +35,10 @@ import javax.annotation.Nonnull;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.IpAddress;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Ipv4Address;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Ipv6Address;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.PortNumber;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstance;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntry;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntryKey;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.port.number.PortType;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.port.number.port.type.SinglePortNumber;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.PortNumber;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.Instance;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntryKey;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -65,9 +63,9 @@ final class MappingEntryCustomizer implements ListWriterCustomizer<MappingEntry,
             throws WriteFailedException {
         // Only static mapping supported by SNAT for now
         checkArgument(dataAfter.getType() ==
-                        org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.MappingEntry.Type.Static,
+                        org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.MappingEntry.Type.Static,
                 "Only static NAT entries are supported currently. Trying to write: %s entry", dataAfter.getType());
-        final Long natInstanceId = id.firstKeyOf(NatInstance.class).getId();
+        final Long natInstanceId = id.firstKeyOf(Instance.class).getId();
         final Long mappingEntryId = id.firstKeyOf(MappingEntry.class).getIndex();
         LOG.debug("Writing mapping entry: {} for nat-instance(vrf): {}", natInstanceId, mappingEntryId);
 
@@ -130,7 +128,7 @@ final class MappingEntryCustomizer implements ListWriterCustomizer<MappingEntry,
     public void deleteCurrentAttributes(@Nonnull final InstanceIdentifier<MappingEntry> id,
                                         @Nonnull final MappingEntry dataBefore,
                                         @Nonnull final WriteContext writeContext) throws WriteFailedException {
-        final long natInstanceId = id.firstKeyOf(NatInstance.class).getId();
+        final long natInstanceId = id.firstKeyOf(Instance.class).getId();
         final MappingEntryKey mappingEntryKey = id.firstKeyOf(MappingEntry.class);
         LOG.debug("Deleting mapping entry: {} for nat-instance(vrf): {}", natInstanceId, mappingEntryKey);
 
@@ -167,14 +165,12 @@ final class MappingEntryCustomizer implements ListWriterCustomizer<MappingEntry,
             request.protocol = protocol.byteValue();
         }
 
-        Optional<Short> internalPortNumber = getPortNumber(id, mappingEntry,
-                (entry) -> Optional.fromNullable(entry.getInternalSrcPort()).transform(PortNumber::getPortType));
-        Optional<Short> externalPortNumber = getPortNumber(id, mappingEntry,
-                (entry) -> Optional.fromNullable(entry.getExternalSrcPort()).transform(PortNumber::getPortType));
-        if (internalPortNumber.isPresent() && externalPortNumber.isPresent()) {
+        final Short internalPortNumber = getPortNumber(id, mappingEntry.getInternalSrcPort());
+        final Short externalPortNumber = getPortNumber(id, mappingEntry.getExternalSrcPort());
+        if (internalPortNumber != null && externalPortNumber != null) {
             request.addrOnly = 0;
-            request.localPort = internalPortNumber.get();
-            request.externalPort = externalPortNumber.get();
+            request.localPort = internalPortNumber;
+            request.externalPort = externalPortNumber;
         }
         return request;
     }
@@ -205,32 +201,24 @@ final class MappingEntryCustomizer implements ListWriterCustomizer<MappingEntry,
             request.proto = protocol.byteValue();
         }
 
-        Optional<Short> internalPortNumber = getPortNumber(id, mappingEntry,
-                (entry) -> Optional.fromNullable(entry.getInternalSrcPort()).transform(PortNumber::getPortType));
-        Optional<Short> externalPortNumber = getPortNumber(id, mappingEntry,
-                (entry) -> Optional.fromNullable(entry.getExternalSrcPort()).transform(PortNumber::getPortType));
-        if (internalPortNumber.isPresent() && externalPortNumber.isPresent()) {
-            request.iPort = internalPortNumber.get();
-            request.oPort = externalPortNumber.get();
+        final Short internalPortNumber = getPortNumber(id, mappingEntry.getInternalSrcPort());
+        final Short externalPortNumber = getPortNumber(id, mappingEntry.getExternalSrcPort());
+        if (internalPortNumber != null && externalPortNumber != null) {
+            request.iPort = internalPortNumber;
+            request.oPort = externalPortNumber;
         }
         return request;
     }
 
-
-    private Optional<Short> getPortNumber(final InstanceIdentifier<MappingEntry> id, final MappingEntry dataAfter,
-                                          final PortGetter portGetter) {
-        return portGetter.getPortType(dataAfter).transform(port -> {
-            if (port instanceof SinglePortNumber) {
-                return ((SinglePortNumber) port).getSinglePortNumber().getValue().shortValue();
+    private Short getPortNumber(final InstanceIdentifier<MappingEntry> id, final PortNumber portNumber) {
+        if (portNumber != null) {
+            if (portNumber.getStartPortNumber() != null && portNumber.getEndPortNumber() == null) {
+                return portNumber.getStartPortNumber().getValue().shortValue();
             } else {
                 throw new IllegalArgumentException(
-                        String.format("Only single port number supported. Submitted: %s for entry: %s",
-                                dataAfter.getInternalSrcPort(), id));
+                    String.format("Only single port number supported. Submitted: %s for entry: %s", portNumber, id));
             }
-        });
-    }
-
-    interface PortGetter {
-        Optional<PortType> getPortType(MappingEntry entry);
+        }
+        return null;
     }
 }
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/Nat64PrefixesCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/Nat64PrefixesCustomizer.java
index b62733e75..33dad0d1b 100644
--- a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/Nat64PrefixesCustomizer.java
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/Nat64PrefixesCustomizer.java
@@ -30,10 +30,10 @@ import io.fd.vpp.jvpp.nat.future.FutureJVppNatFacade;
 import java.util.List;
 import javax.annotation.Nonnull;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Ipv6Prefix;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstance;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.Nat64Prefixes;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.Nat64PrefixesKey;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.nat64.prefixes.DestinationIpv4Prefix;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.Instance;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.Nat64Prefixes;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.Nat64PrefixesKey;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.nat64.prefixes.DestinationIpv4Prefix;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -54,14 +54,10 @@ final class Nat64PrefixesCustomizer
     public void writeCurrentAttributes(@Nonnull final InstanceIdentifier<Nat64Prefixes> id,
                                        @Nonnull final Nat64Prefixes dataAfter,
                                        @Nonnull final WriteContext writeContext) throws WriteFailedException {
-        final int natInstanceId = id.firstKeyOf(NatInstance.class).getId().intValue();
+        final int natInstanceId = id.firstKeyOf(Instance.class).getId().intValue();
         LOG.debug("Configuring nat64 prefix: {} for nat-instance(vrf): {}", dataAfter, natInstanceId);
 
-        // VPP supports only single nat64-prefix per VRF/nat-instance (we map nat-instances to VRFs)
-        // To ensure that (and for simplicity), we require nat64-prefix-id = 0.
-        final Long nat64PrefixId = id.firstKeyOf(Nat64Prefixes.class).getNat64PrefixId();
-        checkArgument(nat64PrefixId == 0, "Only single nat64 prefix is supported (expected id=0, but %s given)",
-                nat64PrefixId);
+        // TODO(HC2VPP-320): ensure at most one prefix is configured per NAT instance
 
         // VPP does not support configuring different nat64-prefixes depending on ipv4 destination prefix:
         final List<DestinationIpv4Prefix> destinationIpv4PrefixList = dataAfter.getDestinationIpv4Prefix();
@@ -77,7 +73,7 @@ final class Nat64PrefixesCustomizer
                                         @Nonnull final Nat64Prefixes dataBefore,
                                         @Nonnull final WriteContext writeContext)
             throws WriteFailedException {
-        final int natInstanceId = id.firstKeyOf(NatInstance.class).getId().intValue();
+        final int natInstanceId = id.firstKeyOf(Instance.class).getId().intValue();
         LOG.debug("Removing nat64 prefix configuration: {} for nat-instance(vrf): {}", dataBefore, natInstanceId);
         // No need for validation here (it was done on write)
         addDelPrefix(id, dataBefore, natInstanceId, false);
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/NatInstaceCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/NatInstaceCustomizer.java
index 8e5673003..22641437f 100644
--- a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/NatInstaceCustomizer.java
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/NatInstaceCustomizer.java
@@ -20,31 +20,31 @@ import io.fd.honeycomb.translate.spi.write.ListWriterCustomizer;
 import io.fd.honeycomb.translate.write.WriteContext;
 import io.fd.honeycomb.translate.write.WriteFailedException;
 import javax.annotation.Nonnull;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstance;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstanceKey;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.Instance;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.InstanceKey;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-final class NatInstaceCustomizer implements ListWriterCustomizer<NatInstance, NatInstanceKey> {
+final class NatInstaceCustomizer implements ListWriterCustomizer<Instance, InstanceKey> {
 
     private static final Logger LOG = LoggerFactory.getLogger(NatInstaceCustomizer.class);
 
     @Override
-    public void writeCurrentAttributes(@Nonnull final InstanceIdentifier<NatInstance> id,
-                                       @Nonnull final NatInstance dataAfter, @Nonnull final WriteContext writeContext)
+    public void writeCurrentAttributes(@Nonnull final InstanceIdentifier<Instance> id,
+                                       @Nonnull final Instance dataAfter, @Nonnull final WriteContext writeContext)
             throws WriteFailedException {
-        LOG.trace("Writing nat-instance: {}", id);
+        LOG.trace("Writing NAT instance: {}", id);
     }
 
     @Override
-    public void deleteCurrentAttributes(@Nonnull final InstanceIdentifier<NatInstance> id,
-                                        @Nonnull final NatInstance dataBefore, @Nonnull final WriteContext writeContext)
+    public void deleteCurrentAttributes(@Nonnull final InstanceIdentifier<Instance> id,
+                                        @Nonnull final Instance dataBefore, @Nonnull final WriteContext writeContext)
             throws WriteFailedException {
-        LOG.trace("Deleting nat-instance: {}", id);
+        LOG.trace("Deleting NAT instance: {}", id);
 
         // For consistency with reader, forbid removing default NAT instance:
-        final Long vrfId = id.firstKeyOf(NatInstance.class).getId();
+        final Long vrfId = id.firstKeyOf(Instance.class).getId();
         if (vrfId == 0) {
             throw new WriteFailedException.DeleteFailedException(id,
                 new UnsupportedOperationException("Removing default NAT instance (vrf=0) is not supported."));
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/NatWriterFactory.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/NatWriterFactory.java
index 802d6875b..ae9e0efca 100644
--- a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/NatWriterFactory.java
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/NatWriterFactory.java
@@ -16,6 +16,12 @@
 
 package io.fd.hc2vpp.nat.write;
 
+import static io.fd.hc2vpp.nat.NatIds.ADDRESS_POOL_ID;
+import static io.fd.hc2vpp.nat.NatIds.MAPPING_ENTRY_ID;
+import static io.fd.hc2vpp.nat.NatIds.NAT64_PREFIXES_ID;
+import static io.fd.hc2vpp.nat.NatIds.NAT_INSTANCE_ID;
+import static io.fd.hc2vpp.nat.NatIds.POLICY_ID;
+
 import com.google.common.collect.Sets;
 import com.google.inject.Inject;
 import io.fd.hc2vpp.nat.util.MappingEntryContext;
@@ -24,17 +30,13 @@ import io.fd.honeycomb.translate.write.WriterFactory;
 import io.fd.honeycomb.translate.write.registry.ModifiableWriterRegistryBuilder;
 import io.fd.vpp.jvpp.nat.future.FutureJVppNatFacade;
 import javax.annotation.Nonnull;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.NatConfig;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.mapping.entry.ExternalSrcPort;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.mapping.entry.InternalSrcPort;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.NatInstances;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstance;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.MappingTable;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntry;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.ExternalIpAddressPool;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.Nat64Prefixes;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.parameters.nat64.prefixes.DestinationIpv4Prefix;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev170804.ExternalIpAddressPoolConfigAugmentation;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.mapping.entry.ExternalSrcPort;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.mapping.entry.InternalSrcPort;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.mapping.table.MappingEntry;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.ExternalIpAddressPool;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.Nat64Prefixes;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.policy.nat64.prefixes.DestinationIpv4Prefix;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.vpp.nat.rev180510.ExternalIpAddressPoolAugmentation;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
 
 /**
@@ -42,12 +44,6 @@ import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  */
 public final class NatWriterFactory implements WriterFactory {
 
-    private static final InstanceIdentifier<NatConfig> NAT_CFG_ID = InstanceIdentifier.create(NatConfig.class);
-    private static final InstanceIdentifier<NatInstance> NAT_INSTANCE_ID =
-            NAT_CFG_ID.child(NatInstances.class).child(NatInstance.class);
-    private static final InstanceIdentifier<MappingEntry> MAP_ENTRY_ID =
-            NAT_INSTANCE_ID.child(MappingTable.class).child(MappingEntry.class);
-
     private final FutureJVppNatFacade jvppNat;
     private final MappingEntryContext mappingEntryContext;
 
@@ -60,26 +56,28 @@ public final class NatWriterFactory implements WriterFactory {
 
     @Override
     public void init(@Nonnull final ModifiableWriterRegistryBuilder registry) {
-        // Nat-instance
+        // +-- nat
+        //    +-- instances/instance
         registry.add(new GenericListWriter<>(NAT_INSTANCE_ID, new NatInstaceCustomizer()));
-        //  Mapping-entry
+        //       +-- mapping-table/mapping-entry
         registry.subtreeAdd(Sets.newHashSet(InstanceIdentifier.create(MappingEntry.class).child(ExternalSrcPort.class),
                 InstanceIdentifier.create(MappingEntry.class).child(InternalSrcPort.class)),
-                new GenericListWriter<>(MAP_ENTRY_ID, new MappingEntryCustomizer(jvppNat, mappingEntryContext)));
+                new GenericListWriter<>(MAPPING_ENTRY_ID, new MappingEntryCustomizer(jvppNat, mappingEntryContext)));
+
+        //       +-- policy
+        registry.add(new GenericListWriter<>(POLICY_ID, new PolicyCustomizer()));
 
-        // External address pool has to be executed before mapping entry. Because adding mapping entries requires to
-        //  already have an IP range predefined ... in some cases
+        //          +-- external-ip-address-pool
         registry.subtreeAddBefore(
-                Sets.newHashSet(InstanceIdentifier.create(ExternalIpAddressPool.class)
-                                .augmentation(ExternalIpAddressPoolConfigAugmentation.class)),
-                        new GenericListWriter<>(NAT_INSTANCE_ID.child(ExternalIpAddressPool.class),
-                new ExternalIpPoolCustomizer(jvppNat)),
-                MAP_ENTRY_ID);
+            // External address pool has to be executed before mapping entry. Because adding mapping entries
+            // requires to already have an IP range predefined ... in some cases
+            Sets.newHashSet(InstanceIdentifier.create(ExternalIpAddressPool.class)
+                .augmentation(ExternalIpAddressPoolAugmentation.class)),
+            new GenericListWriter<>(ADDRESS_POOL_ID, new ExternalIpPoolCustomizer(jvppNat)), MAPPING_ENTRY_ID);
 
-        // nat64-prefixes
+        //          +-- nat64-prefixes
         registry.subtreeAdd(
                 Sets.newHashSet(InstanceIdentifier.create(Nat64Prefixes.class).child(DestinationIpv4Prefix.class)),
-                new GenericListWriter<>(NAT_INSTANCE_ID.child(Nat64Prefixes.class),
-                        new Nat64PrefixesCustomizer(jvppNat)));
+                new GenericListWriter<>(NAT64_PREFIXES_ID, new Nat64PrefixesCustomizer(jvppNat)));
     }
 }
diff --git a/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/PolicyCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/PolicyCustomizer.java
new file mode 100644
index 000000000..ecc340f38
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/hc2vpp/nat/write/PolicyCustomizer.java
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2018 Cisco and/or its affiliates.
+ *
+ * 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 io.fd.hc2vpp.nat.write;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import io.fd.honeycomb.translate.spi.write.ListWriterCustomizer;
+import io.fd.honeycomb.translate.write.WriteContext;
+import io.fd.honeycomb.translate.write.WriteFailedException;
+import javax.annotation.Nonnull;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.Instance;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.Policy;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev180223.nat.instances.instance.PolicyKey;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+final class PolicyCustomizer implements ListWriterCustomizer<Policy, PolicyKey> {
+
+    private static final Logger LOG = LoggerFactory.getLogger(PolicyCustomizer.class);
+
+    @Override
+    public void writeCurrentAttributes(@Nonnull final InstanceIdentifier<Policy> id,
+                                       @Nonnull final Policy dataAfter, @Nonnull final WriteContext writeContext)
+            throws WriteFailedException {
+        LOG.trace("Writing NAT policy: {}", id);
+
+        // HC supports only single NAT policy per NAT instance (VRF)
+        // To ensure that (and for simplicity), we require policy id = 0.
+        final Long policyId = id.firstKeyOf(Policy.class).getId();
+        checkArgument(policyId == 0,
+            "Only single policy per NAT instance (VRF) is supported (expected id=0, but %s given)", policyId);
+    }
+
+    @Override
+    public void deleteCurrentAttributes(@Nonnull final InstanceIdentifier<Policy> id,
+                                        @Nonnull final Policy dataBefore, @Nonnull final WriteContext writeContext)
+            throws WriteFailedException {
+        LOG.trace("Deleting NAT policy: {}", id);
+    }
+}