HONEYCOMB-229 Introduce NAT to HC

Reflects SNAT from VPP:
- 1:1 Static IPv4 mapping
- interface in/out NAT feature management

Bonus:
- Support presence containers in infra

Change-Id: Ieb38526f83edbae5e605d5c7e39bb22bbafc50e5
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>

20 files changed, 1764 insertions, 0 deletions

diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/NatModule.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/NatModule.java
new file mode 100644
index 000000000..b33f900e5
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/NatModule.java
@@ -0,0 +1,77 @@
+/*
+ * 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.honeycomb.nat;
+
+import com.google.common.annotations.VisibleForTesting;
+import com.google.inject.AbstractModule;
+import com.google.inject.Provider;
+import com.google.inject.Singleton;
+import com.google.inject.multibindings.Multibinder;
+import io.fd.honeycomb.data.init.DataTreeInitializer;
+import io.fd.honeycomb.nat.init.NatInitializer;
+import io.fd.honeycomb.nat.jvpp.JVppSnatProvider;
+import io.fd.honeycomb.nat.read.NatReaderFactory;
+import io.fd.honeycomb.nat.read.ifc.IfcNatReaderFactory;
+import io.fd.honeycomb.nat.util.MappingEntryContext;
+import io.fd.honeycomb.nat.write.NatWriterFactory;
+import io.fd.honeycomb.nat.write.ifc.IfcNatWriterFactory;
+import io.fd.honeycomb.translate.read.ReaderFactory;
+import io.fd.honeycomb.translate.write.WriterFactory;
+import io.fd.vpp.jvpp.snat.future.FutureJVppSnatFacade;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Module class instantiating nat plugin components.
+ */
+public final class NatModule extends AbstractModule {
+
+    private static final Logger LOG = LoggerFactory.getLogger(NatModule.class);
+    private final Class<? extends Provider<FutureJVppSnatFacade>> jvppSnatProviderClass;
+
+    public NatModule() {
+        this(JVppSnatProvider.class);
+    }
+
+    @VisibleForTesting
+    NatModule(Class<? extends Provider<FutureJVppSnatFacade>> jvppSnatProvider) {
+        this.jvppSnatProviderClass = jvppSnatProvider;
+    }
+
+    @Override
+    protected void configure() {
+        // Mapping entry context util
+        bind(MappingEntryContext.class).toInstance(new MappingEntryContext());
+
+        LOG.debug("Installing NAT module");
+
+        // Bind to Plugin's JVPP
+        bind(FutureJVppSnatFacade.class).toProvider(jvppSnatProviderClass).in(Singleton.class);
+
+        final Multibinder<ReaderFactory> readBinder = Multibinder.newSetBinder(binder(), ReaderFactory.class);
+        readBinder.addBinding().to(IfcNatReaderFactory.class).in(Singleton.class);
+        readBinder.addBinding().to(NatReaderFactory.class).in(Singleton.class);
+
+        final Multibinder<WriterFactory> writeBinder = Multibinder.newSetBinder(binder(), WriterFactory.class);
+        writeBinder.addBinding().to(IfcNatWriterFactory.class).in(Singleton.class);
+        writeBinder.addBinding().to(NatWriterFactory.class).in(Singleton.class);
+
+        Multibinder.newSetBinder(binder(), DataTreeInitializer.class)
+                .addBinding().to(NatInitializer.class).in(Singleton.class);
+        LOG.info("Module NAT successfully configured");
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/init/NatInitializer.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/init/NatInitializer.java
new file mode 100644
index 000000000..37c456133
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/init/NatInitializer.java
@@ -0,0 +1,63 @@
+/*
+ * 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.honeycomb.nat.init;
+
+import com.google.inject.Inject;
+import com.google.inject.name.Named;
+import io.fd.honeycomb.data.init.AbstractDataTreeConverter;
+import java.util.stream.Collectors;
+import javax.annotation.Nonnull;
+import org.opendaylight.controller.md.sal.binding.api.DataBroker;
+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.NatConfigBuilder;
+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.nat.config.NatInstancesBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.NatInstanceBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.MappingTableBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.nat.config.nat.instances.nat.instance.mapping.table.MappingEntryBuilder;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+/**
+ * Initialize nat-config from nat-state.
+ */
+public final class NatInitializer extends AbstractDataTreeConverter<NatState, NatConfig> {
+
+    @Inject
+    public NatInitializer(@Named("honeycomb-initializer") @Nonnull final DataBroker bindingDataBroker) {
+        super(bindingDataBroker, InstanceIdentifier.create(NatState.class), InstanceIdentifier.create(NatConfig.class));
+    }
+
+    @Override
+    public NatConfig convert(final NatState operationalData) {
+        return new NatConfigBuilder()
+                .setNatInstances(new NatInstancesBuilder()
+                        .setNatInstance(operationalData.getNatInstances().getNatInstance().stream()
+                                .map(operNatInstance -> new NatInstanceBuilder()
+                                        .setId(operNatInstance.getId())
+                                        .setMappingTable(new MappingTableBuilder()
+                                                .setMappingEntry(
+                                                        operNatInstance.getMappingTable().getMappingEntry().stream()
+                                                                .map(operEntry -> new MappingEntryBuilder(operEntry).build())
+                                                                .collect(Collectors.toList()))
+                                                .build())
+                                        .build())
+                                .collect(Collectors.toList()))
+                        .build())
+                .build();
+        // TODO implement initialization for nat inbound/outbound NAT feature after VPP-459
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/jvpp/JVppSnatProvider.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/jvpp/JVppSnatProvider.java
new file mode 100755
index 000000000..b83665679
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/jvpp/JVppSnatProvider.java
@@ -0,0 +1,60 @@
+/*
+ * 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.honeycomb.nat.jvpp;
+
+import com.google.inject.Inject;
+import io.fd.honeycomb.infra.distro.ProviderTrait;
+import io.fd.vpp.jvpp.JVppRegistry;
+import io.fd.vpp.jvpp.snat.JVppSnatImpl;
+import io.fd.vpp.jvpp.snat.future.FutureJVppSnatFacade;
+import java.io.IOException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Provides future API for jvpp-nsh plugin. Must be a singleton due to shutdown hook usage.
+ * Registers shutdown hook to free plugin's resources on shutdown.
+ */
+public final class JVppSnatProvider extends ProviderTrait<FutureJVppSnatFacade> {
+
+    private static final Logger LOG = LoggerFactory.getLogger(JVppSnatProvider.class);
+
+    @Inject
+    private JVppRegistry registry;
+
+    @Override
+    protected FutureJVppSnatFacade create() {
+        try {
+            final JVppSnatImpl jvppSnat = new JVppSnatImpl();
+            // Free jvpp-nsh plugin's resources on shutdown
+            Runtime.getRuntime().addShutdownHook(new Thread() {
+                @Override
+                public void run() {
+                    LOG.info("Unloading jvpp-snat plugin");
+                    jvppSnat.close();
+                    LOG.info("Successfully unloaded jvpp-snat plugin");
+                }
+            });
+
+            LOG.info("Successfully loaded jvpp-snat plugin");
+            return new FutureJVppSnatFacade(registry, jvppSnat);
+        } catch (IOException e) {
+            throw new IllegalStateException("Unable to open VPP management connection", e);
+        }
+    }
+}
+
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/MappingEntryCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/MappingEntryCustomizer.java
new file mode 100644
index 000000000..469d361ee
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/MappingEntryCustomizer.java
@@ -0,0 +1,151 @@
+/*
+ * 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.honeycomb.nat.read;
+
+import io.fd.honeycomb.nat.util.MappingEntryContext;
+import io.fd.honeycomb.translate.read.ReadContext;
+import io.fd.honeycomb.translate.read.ReadFailedException;
+import io.fd.honeycomb.translate.spi.read.ListReaderCustomizer;
+import io.fd.honeycomb.translate.util.read.cache.DumpCacheManager;
+import io.fd.honeycomb.translate.util.read.cache.EntityDumpExecutor;
+import io.fd.honeycomb.translate.vpp.util.Ipv4Translator;
+import io.fd.honeycomb.translate.vpp.util.JvppReplyConsumer;
+import io.fd.vpp.jvpp.snat.dto.SnatStaticMappingDetails;
+import io.fd.vpp.jvpp.snat.dto.SnatStaticMappingDetailsReplyDump;
+import io.fd.vpp.jvpp.snat.dto.SnatStaticMappingDump;
+import io.fd.vpp.jvpp.snat.future.FutureJVppSnatFacade;
+import java.util.List;
+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.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.yangtools.concepts.Builder;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class MappingEntryCustomizer implements Ipv4Translator,
+        ListReaderCustomizer<MappingEntry, MappingEntryKey, MappingEntryBuilder> {
+
+    private static final Logger LOG = LoggerFactory.getLogger(MappingEntryCustomizer.class);
+
+    private final DumpCacheManager<SnatStaticMappingDetailsReplyDump, Void> dumpCacheManager;
+    private final MappingEntryContext mappingEntryContext;
+
+    public MappingEntryCustomizer(final DumpCacheManager<SnatStaticMappingDetailsReplyDump, Void> dumpCacheManager,
+                                  final MappingEntryContext mappingEntryContext) {
+        this.dumpCacheManager = dumpCacheManager;
+        this.mappingEntryContext = mappingEntryContext;
+    }
+
+    @Nonnull
+    @Override
+    public MappingEntryBuilder getBuilder(@Nonnull final InstanceIdentifier<MappingEntry> id) {
+        return new MappingEntryBuilder();
+    }
+
+    @Override
+    public void readCurrentAttributes(@Nonnull final InstanceIdentifier<MappingEntry> id,
+                                      @Nonnull final MappingEntryBuilder builder, @Nonnull final ReadContext ctx)
+            throws ReadFailedException {
+        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 List<SnatStaticMappingDetails> details =
+                dumpCacheManager.getDump(id, getClass().getName(), ctx.getModificationCache(), null)
+                        .or(new SnatStaticMappingDetailsReplyDump()).snatStaticMappingDetails;
+        final SnatStaticMappingDetails snatStaticMappingDetails =
+                mappingEntryContext.findDetails(details, natInstanceId, idx, ctx.getMappingContext());
+
+        builder.setIndex((long) idx);
+        builder.setType(
+                org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.MappingEntry.Type.Static);
+        // Snat only supports ipv4 for now
+        builder.setExternalSrcAddress(arrayToIpv4AddressNoZoneReversed(snatStaticMappingDetails.externalIpAddress));
+        builder.setInternalSrcAddress(
+                new IpAddress(arrayToIpv4AddressNoZoneReversed(snatStaticMappingDetails.localIpAddress)));
+
+        if (snatStaticMappingDetails.addrOnly == 0) {
+            builder.setExternalSrcPort(new ExternalSrcPortBuilder()
+                    .setPortType(new SinglePortNumberBuilder().setSinglePortNumber(new PortNumber(
+                            (int) snatStaticMappingDetails.externalPort))
+                            .build())
+                    .build());
+            builder.setInternalSrcPort(new InternalSrcPortBuilder()
+                    .setPortType(new SinglePortNumberBuilder().setSinglePortNumber(new PortNumber(
+                            (int) snatStaticMappingDetails.localPort))
+                            .build())
+                    .build());
+        }
+
+        LOG.trace("Mapping-entry read as: {}", builder);
+    }
+
+    @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();
+        LOG.trace("Listing IDs for all mapping-entries within nat-instance(vrf):{}", natInstanceId);
+
+        final List<MappingEntryKey> entryKeys =
+                dumpCacheManager.getDump(id, getClass().getName(), context.getModificationCache(), null)
+                        .or(new SnatStaticMappingDetailsReplyDump()).snatStaticMappingDetails.stream()
+                        .filter(detail -> natInstanceId == detail.vrfId)
+                        .map(detail -> mappingEntryContext
+                                .getStoredOrArtificialIndex(natInstanceId, detail, context.getMappingContext()))
+                        .map(MappingEntryKey::new)
+                        .collect(Collectors.toList());
+        LOG.debug("List of mapping-entry keys within nat-instance(vrf):{} : {}", natInstanceId, entryKeys);
+
+        return entryKeys;
+    }
+
+    @Override
+    public void merge(@Nonnull final Builder<? extends DataObject> builder,
+                      @Nonnull final List<MappingEntry> readData) {
+        ((MappingTableBuilder) builder).setMappingEntry(readData);
+    }
+
+    static final class MappingEntryDumpExecutor
+            implements EntityDumpExecutor<SnatStaticMappingDetailsReplyDump, Void>, JvppReplyConsumer {
+
+        private final FutureJVppSnatFacade jvppSnat;
+
+        MappingEntryDumpExecutor(final FutureJVppSnatFacade jvppSnat) {
+            this.jvppSnat = jvppSnat;
+        }
+
+        @Nonnull
+        @Override
+        public SnatStaticMappingDetailsReplyDump executeDump(final InstanceIdentifier<?> identifier, final Void params)
+                throws ReadFailedException {
+            return getReplyForRead(jvppSnat.snatStaticMappingDump(new SnatStaticMappingDump()).toCompletableFuture(),
+                    identifier);
+        }
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/NatInstanceCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/NatInstanceCustomizer.java
new file mode 100644
index 000000000..cb639b962
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/NatInstanceCustomizer.java
@@ -0,0 +1,84 @@
+/*
+ * 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.honeycomb.nat.read;
+
+import io.fd.honeycomb.translate.read.ReadContext;
+import io.fd.honeycomb.translate.read.ReadFailedException;
+import io.fd.honeycomb.translate.spi.read.ListReaderCustomizer;
+import io.fd.honeycomb.translate.util.read.cache.DumpCacheManager;
+import io.fd.vpp.jvpp.snat.dto.SnatStaticMappingDetailsReplyDump;
+import java.util.List;
+import java.util.stream.Collectors;
+import javax.annotation.Nonnull;
+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.yangtools.concepts.Builder;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Nat instance ID is mapped to VRF-ID in VPP.
+ */
+final class NatInstanceCustomizer implements ListReaderCustomizer<NatInstance, NatInstanceKey, NatInstanceBuilder> {
+
+    private static final Logger LOG = LoggerFactory.getLogger(NatInstanceCustomizer.class);
+
+    private final DumpCacheManager<SnatStaticMappingDetailsReplyDump, Void> dumpCacheManager;
+
+    public NatInstanceCustomizer(final DumpCacheManager<SnatStaticMappingDetailsReplyDump, Void> dumpCacheManager) {
+        this.dumpCacheManager = dumpCacheManager;
+    }
+
+    @Nonnull
+    @Override
+    public NatInstanceBuilder getBuilder(@Nonnull final InstanceIdentifier<NatInstance> id) {
+        return new NatInstanceBuilder();
+    }
+
+    @Override
+    public void readCurrentAttributes(@Nonnull final InstanceIdentifier<NatInstance> id,
+                                      @Nonnull final NatInstanceBuilder builder, @Nonnull final ReadContext ctx)
+            throws ReadFailedException {
+        LOG.trace("Reading current attributes for nat-instance: {}", id);
+        builder.setId(id.firstKeyOf(NatInstance.class).getId());
+    }
+
+    @Nonnull
+    @Override
+    public List<NatInstanceKey> getAllIds(@Nonnull final InstanceIdentifier<NatInstance> id,
+                                          @Nonnull final ReadContext context) throws ReadFailedException {
+        LOG.trace("Listing IDs for all nat-instances");
+        final List<NatInstanceKey> vrfIds =
+                dumpCacheManager.getDump(id, getClass().getName(), context.getModificationCache(), null)
+                        .or(new SnatStaticMappingDetailsReplyDump()).snatStaticMappingDetails.stream()
+                        .map(detail -> detail.vrfId)
+                        .map(vrfId -> new NatInstanceKey((long)vrfId))
+                        .collect(Collectors.toList());
+
+        LOG.debug("List of nat-instance keys (vrf-ids): {}", vrfIds);
+        return vrfIds;
+    }
+
+    @Override
+    public void merge(@Nonnull final Builder<? extends DataObject> builder, @Nonnull final List<NatInstance> readData) {
+        ((NatInstancesBuilder) builder).setNatInstance(readData);
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/NatReaderFactory.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/NatReaderFactory.java
new file mode 100644
index 000000000..949009c62
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/NatReaderFactory.java
@@ -0,0 +1,75 @@
+/*
+ * 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.honeycomb.nat.read;
+
+import com.google.common.collect.Sets;
+import com.google.inject.Inject;
+import io.fd.honeycomb.nat.util.MappingEntryContext;
+import io.fd.honeycomb.translate.impl.read.GenericListReader;
+import io.fd.honeycomb.translate.read.ReaderFactory;
+import io.fd.honeycomb.translate.read.registry.ModifiableReaderRegistryBuilder;
+import io.fd.honeycomb.translate.util.read.cache.DumpCacheManager;
+import io.fd.vpp.jvpp.snat.dto.SnatStaticMappingDetailsReplyDump;
+import io.fd.vpp.jvpp.snat.future.FutureJVppSnatFacade;
+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.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.mapping.table.MappingEntry;
+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<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 MappingEntryContext mappingEntryContext;
+    private final DumpCacheManager<SnatStaticMappingDetailsReplyDump, Void> dumpCacheManager;
+
+    @Inject
+    public NatReaderFactory(final FutureJVppSnatFacade jvppSnat,
+                            final MappingEntryContext mappingEntryContext) {
+        this.mappingEntryContext = mappingEntryContext;
+        this.dumpCacheManager = new DumpCacheManager.DumpCacheManagerBuilder<SnatStaticMappingDetailsReplyDump, Void>()
+                .withExecutor(new MappingEntryCustomizer.MappingEntryDumpExecutor(jvppSnat))
+                .build();
+    }
+
+    @Override
+    public void init(@Nonnull final ModifiableReaderRegistryBuilder registry) {
+        registry.addStructuralReader(NAT_OPER_ID, NatStateBuilder.class);
+        registry.addStructuralReader(NAT_INSTANCES_ID, NatInstancesBuilder.class);
+        registry.add(new GenericListReader<>(NAT_INSTANCE_ID, new NatInstanceCustomizer(dumpCacheManager)));
+        registry.addStructuralReader(MAP_TABLE_ID, MappingTableBuilder.class);
+        registry.subtreeAdd(Sets.newHashSet(InstanceIdentifier.create(MappingEntry.class).child(ExternalSrcPort.class),
+                InstanceIdentifier.create(MappingEntry.class).child(InternalSrcPort.class)),
+                new GenericListReader<>(MAP_ENTRY_ID,
+                        new MappingEntryCustomizer(dumpCacheManager, mappingEntryContext)));
+
+        // TODO VPP-453 Implement address range read
+
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/ifc/IfcNatReaderFactory.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/ifc/IfcNatReaderFactory.java
new file mode 100644
index 000000000..293a3dfd9
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/ifc/IfcNatReaderFactory.java
@@ -0,0 +1,55 @@
+/*
+ * 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.honeycomb.nat.read.ifc;
+
+
+import io.fd.honeycomb.translate.impl.read.GenericReader;
+import io.fd.honeycomb.translate.read.ReaderFactory;
+import io.fd.honeycomb.translate.read.registry.ModifiableReaderRegistryBuilder;
+import javax.annotation.Nonnull;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.InterfacesState;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.state.Interface;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214.NatInterfaceStateAugmentation;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214.NatInterfaceStateAugmentationBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.Nat;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.NatBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.nat.Inbound;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.nat.Outbound;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+/**
+ * Factory producing readers for nat plugin's data.
+ */
+public final class IfcNatReaderFactory implements ReaderFactory {
+
+    private static final InstanceIdentifier<Interface>
+            IFC_ID = InstanceIdentifier.create(InterfacesState.class).child(Interface.class);
+    private static final InstanceIdentifier<NatInterfaceStateAugmentation> NAT_AUG_ID =
+            IFC_ID.augmentation(NatInterfaceStateAugmentation.class);
+    private static final InstanceIdentifier<Nat> NAT_AUG_CONTAINER_ID = NAT_AUG_ID.child(Nat.class);
+
+    @Override
+    public void init(@Nonnull final ModifiableReaderRegistryBuilder registry) {
+        registry.addStructuralReader(NAT_AUG_ID, NatInterfaceStateAugmentationBuilder.class);
+        registry.addStructuralReader(NAT_AUG_CONTAINER_ID, NatBuilder.class);
+
+        registry.addAfter(
+                new GenericReader<>(NAT_AUG_CONTAINER_ID.child(Inbound.class), new InterfaceInboundNatCustomizer()), IFC_ID);
+        registry.addAfter(
+                new GenericReader<>(NAT_AUG_CONTAINER_ID.child(Outbound.class), new InterfaceOutboundNatCustomizer()), IFC_ID);
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/ifc/InterfaceInboundNatCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/ifc/InterfaceInboundNatCustomizer.java
new file mode 100644
index 000000000..e1ebdd6d8
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/ifc/InterfaceInboundNatCustomizer.java
@@ -0,0 +1,55 @@
+/*
+ * 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.honeycomb.nat.read.ifc;
+
+import io.fd.honeycomb.translate.read.ReadContext;
+import io.fd.honeycomb.translate.read.ReadFailedException;
+import io.fd.honeycomb.translate.spi.read.ReaderCustomizer;
+import javax.annotation.Nonnull;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.NatBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.nat.Inbound;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.nat.InboundBuilder;
+import org.opendaylight.yangtools.concepts.Builder;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public final class InterfaceInboundNatCustomizer implements ReaderCustomizer<Inbound, InboundBuilder> {
+
+    private static final Logger LOG = LoggerFactory.getLogger(InterfaceInboundNatCustomizer.class);
+
+    @Nonnull
+    @Override
+    public InboundBuilder getBuilder(@Nonnull final InstanceIdentifier<Inbound> id) {
+        return new InboundBuilder();
+    }
+
+    @Override
+    public void readCurrentAttributes(@Nonnull final InstanceIdentifier<Inbound> id,
+                                      @Nonnull final InboundBuilder builder,
+                                      @Nonnull final ReadContext ctx)
+            throws ReadFailedException {
+        // FIXME HONEYCOMB-248 VPP-459 Implement when read is available in VPP/Snat
+        LOG.debug("Unable to read Inbound NAT feature state for an interface");
+    }
+
+    @Override
+    public void merge(@Nonnull final Builder<? extends DataObject> parentBuilder, @Nonnull final Inbound readValue) {
+        ((NatBuilder) parentBuilder).setInbound(readValue);
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/ifc/InterfaceOutboundNatCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/ifc/InterfaceOutboundNatCustomizer.java
new file mode 100644
index 000000000..fe28584ff
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/read/ifc/InterfaceOutboundNatCustomizer.java
@@ -0,0 +1,54 @@
+/*
+ * 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.honeycomb.nat.read.ifc;
+
+import io.fd.honeycomb.translate.read.ReadContext;
+import io.fd.honeycomb.translate.read.ReadFailedException;
+import io.fd.honeycomb.translate.spi.read.ReaderCustomizer;
+import javax.annotation.Nonnull;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.NatBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.nat.Outbound;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.nat.OutboundBuilder;
+import org.opendaylight.yangtools.concepts.Builder;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public final class InterfaceOutboundNatCustomizer implements ReaderCustomizer<Outbound, OutboundBuilder> {
+
+    private static final Logger LOG = LoggerFactory.getLogger(InterfaceOutboundNatCustomizer.class);
+
+    @Nonnull
+    @Override
+    public OutboundBuilder getBuilder(@Nonnull final InstanceIdentifier<Outbound> id) {
+        return new OutboundBuilder();
+    }
+
+    @Override
+    public void readCurrentAttributes(@Nonnull final InstanceIdentifier<Outbound> id,
+                                      @Nonnull final OutboundBuilder builder, @Nonnull final ReadContext ctx)
+            throws ReadFailedException {
+        // FIXME HONEYCOMB-248 VPP-459 Implement when read is available in VPP/Snat
+        LOG.debug("Unable to read Outbound NAT feature state for an interface");
+    }
+
+    @Override
+    public void merge(@Nonnull final Builder<? extends DataObject> parentBuilder, @Nonnull final Outbound readValue) {
+        ((NatBuilder) parentBuilder).setOutbound(readValue);
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/util/MappingEntryContext.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/util/MappingEntryContext.java
new file mode 100644
index 000000000..0f2df7e1d
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/util/MappingEntryContext.java
@@ -0,0 +1,210 @@
+/*
+ * 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.honeycomb.nat.util;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Optional;
+import io.fd.honeycomb.translate.MappingContext;
+import io.fd.honeycomb.translate.vpp.util.Ipv4Translator;
+import io.fd.vpp.jvpp.snat.dto.SnatStaticMappingDetails;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+import javax.annotation.Nonnull;
+import javax.annotation.concurrent.ThreadSafe;
+import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.naming.context.rev160513.Contexts;
+import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.nat.context.rev161214.NatMappingEntryCtxAugmentation;
+import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.nat.context.rev161214.mapping.entry.context.attributes.NatMappingEntryContext;
+import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.nat.context.rev161214.mapping.entry.context.attributes.nat.mapping.entry.context.NatInstance;
+import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.nat.context.rev161214.mapping.entry.context.attributes.nat.mapping.entry.context.NatInstanceKey;
+import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.nat.context.rev161214.mapping.entry.context.attributes.nat.mapping.entry.context.nat.instance.MappingTable;
+import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.nat.context.rev161214.mapping.entry.context.attributes.nat.mapping.entry.context.nat.instance.mapping.table.MappingEntry;
+import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.nat.context.rev161214.mapping.entry.context.attributes.nat.mapping.entry.context.nat.instance.mapping.table.MappingEntryBuilder;
+import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.nat.context.rev161214.mapping.entry.context.attributes.nat.mapping.entry.context.nat.instance.mapping.table.MappingEntryKey;
+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.yangtools.yang.binding.InstanceIdentifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Context tracker for Nat Mapping entries.
+ */
+@ThreadSafe
+public class MappingEntryContext implements Ipv4Translator {
+
+    private static final Logger LOG = LoggerFactory.getLogger(MappingEntryContext.class);
+
+    /**
+     * Add mapping entry to index mapping to context.
+     */
+    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 MappingContext mappingContext) {
+        final InstanceIdentifier<MappingEntry> id = getId(natInstanceId, entryToKey(entry));
+        checkArgument(!containsEntry(natInstanceId, entry, mappingContext), "Mapping for %s already present", id);
+        mappingContext.put(id, toCtxMapEntry(entry, entryId));
+    }
+
+    /**
+     * 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 MappingContext mappingContext) {
+        final InstanceIdentifier<MappingEntry> id = getId(natInstanceId, entryToKey(entry));
+        return mappingContext.read(id).isPresent();
+    }
+
+    @VisibleForTesting
+    static InstanceIdentifier<MappingEntry> getId(final Long natInstanceId, final MappingEntryKey key) {
+        return getTableId(natInstanceId).child(MappingEntry.class, key);
+    }
+
+    @VisibleForTesting
+    static InstanceIdentifier<MappingTable> getTableId(final long natInstanceId) {
+        return InstanceIdentifier.create(Contexts.class)
+                .augmentation(NatMappingEntryCtxAugmentation.class)
+                .child(NatMappingEntryContext.class)
+                .child(NatInstance.class, new NatInstanceKey(natInstanceId))
+                .child(MappingTable.class);
+    }
+
+    @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) {
+        // Only IPv4
+        return new MappingEntryKey(new IpAddress(entry.getExternalSrcAddress()), entry.getInternalSrcAddress());
+    }
+
+    private MappingEntryKey entryToKey(final SnatStaticMappingDetails entry) {
+        // Only IPv4
+        return new MappingEntryKey(
+                new IpAddress(new Ipv4Address(arrayToIpv4AddressNoZoneReversed(entry.externalIpAddress))),
+                new IpAddress(new Ipv4Address(arrayToIpv4AddressNoZoneReversed(entry.localIpAddress))));
+    }
+
+    private boolean equalEntries(final SnatStaticMappingDetails detail, final MappingEntry ctxMappingEntry) {
+        final IpAddress internalAddrFromDetails =
+                new IpAddress(new Ipv4Address(arrayToIpv4AddressNoZoneReversed(detail.localIpAddress)));
+        // Only IPv4
+        if (!ctxMappingEntry.getInternal().equals(internalAddrFromDetails)) {
+            return false;
+        }
+        // Only IPv4
+        final IpAddress externalAddrFromDetails =
+                new IpAddress(new Ipv4Address(arrayToIpv4AddressNoZoneReversed(detail.externalIpAddress)));
+        if (!ctxMappingEntry.getExternal().equals(externalAddrFromDetails)) {
+            return false;
+        }
+        return true;
+    }
+
+    @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,
+            final long entryId) {
+        return new MappingEntryBuilder()
+                .setKey(entryToKey(entry))
+                .setIndex(entryId)
+                .build();
+    }
+
+    private MappingEntry toCtxMapEntry(@Nonnull final SnatStaticMappingDetails details, final long entryId) {
+        return new MappingEntryBuilder()
+                .setKey(entryToKey(details))
+                .setIndex(entryId)
+                .build();
+    }
+
+    /**
+     * 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 MappingContext mappingContext) {
+        mappingContext.delete(getId(natInstanceId, entryToKey(entry)));
+    }
+
+    /**
+     * Find specific details in provided collection identified with provided index.
+     */
+    public synchronized SnatStaticMappingDetails findDetails(@Nonnull final List<SnatStaticMappingDetails> details,
+                                                             final long natInstanceId, final long idx,
+                                                             @Nonnull final MappingContext mappingContext) {
+        // Find mapping entry for Index
+        final MappingEntry ctxMappingEntry = mappingContext.read(getTableId(natInstanceId))
+                .transform(MappingTable::getMappingEntry)
+                .or(Collections.emptyList())
+                .stream()
+                .filter(entry -> entry.getIndex() == idx)
+                .findFirst()
+                .orElseThrow(() -> new IllegalStateException("Unable to find context mapping for nat-instance: "
+                        + natInstanceId + " and ID: " + idx));
+
+        // Find which details matches the context stored entry under index
+        return details.stream()
+                .filter(detail -> equalEntries(detail, ctxMappingEntry))
+                .findFirst()
+                .orElseThrow(() -> new IllegalStateException("Unable to match mapping for nat-instance: "
+                        + natInstanceId + " and match: " + ctxMappingEntry + " in: " + details));
+    }
+
+    /**
+     * Get index for a mapping entry details or create an artificial one.
+     */
+    public synchronized long getStoredOrArtificialIndex(final Long natInstanceId,
+                                                        @Nonnull final SnatStaticMappingDetails details,
+                                                        @Nonnull final MappingContext mappingContext) {
+        return mappingContext.read(getId(natInstanceId, entryToKey(details)))
+                .transform(MappingEntry::getIndex)
+                .or(() -> getArtificialId(details, natInstanceId, mappingContext));
+    }
+
+    /**
+     * 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 MappingContext mappingContext) {
+        return mappingContext.read(getId(natInstanceId, entryToKey(entry)))
+                .transform(MappingEntry::getIndex);
+    }
+
+    private long getArtificialId(final SnatStaticMappingDetails details, final Long natInstanceId,
+                                 final MappingContext mappingContext) {
+        LOG.trace("Assigning artificial ID for {}", details);
+        final long artificialIdx = findFreeIndex(natInstanceId, mappingContext);
+        LOG.debug("Artificial ID for {} assigned as: {}", details, artificialIdx);
+        mappingContext.put(getId(natInstanceId, entryToKey(details)), toCtxMapEntry(details, artificialIdx));
+        return artificialIdx;
+    }
+
+    private long findFreeIndex(final long natInstanceId, final MappingContext mappingContext) {
+        return mappingContext.read(getTableId(natInstanceId))
+                .transform(MappingTable::getMappingEntry)
+                .or(Collections.emptyList())
+                .stream()
+                .map(MappingEntry::getIndex)
+                .max(Comparator.naturalOrder())
+                .map(i -> i + 1)
+                .orElse(0L);
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/MappingEntryCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/MappingEntryCustomizer.java
new file mode 100644
index 000000000..785606942
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/MappingEntryCustomizer.java
@@ -0,0 +1,182 @@
+/*
+ * 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.honeycomb.nat.write;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import com.google.common.base.Optional;
+import io.fd.honeycomb.nat.util.MappingEntryContext;
+import io.fd.honeycomb.translate.spi.write.ListWriterCustomizer;
+import io.fd.honeycomb.translate.vpp.util.Ipv4Translator;
+import io.fd.honeycomb.translate.vpp.util.JvppReplyConsumer;
+import io.fd.honeycomb.translate.write.WriteContext;
+import io.fd.honeycomb.translate.write.WriteFailedException;
+import io.fd.vpp.jvpp.snat.dto.SnatAddStaticMapping;
+import io.fd.vpp.jvpp.snat.future.FutureJVppSnatFacade;
+import javax.annotation.Nonnull;
+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.yangtools.yang.binding.InstanceIdentifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+final class MappingEntryCustomizer implements ListWriterCustomizer<MappingEntry, MappingEntryKey>,
+        JvppReplyConsumer, Ipv4Translator {
+
+    private static final Logger LOG = LoggerFactory.getLogger(MappingEntryCustomizer.class);
+
+    private final FutureJVppSnatFacade jvppSnat;
+    private final MappingEntryContext mappingEntryContext;
+
+    MappingEntryCustomizer(final FutureJVppSnatFacade jvppSnat, final MappingEntryContext mappingEntryContext) {
+        this.jvppSnat = jvppSnat;
+        this.mappingEntryContext = mappingEntryContext;
+    }
+
+    @Override
+    public void writeCurrentAttributes(@Nonnull final InstanceIdentifier<MappingEntry> id,
+                                       @Nonnull final MappingEntry dataAfter,
+                                       @Nonnull final WriteContext writeContext)
+            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,
+                "Only static NAT entries are supported currently. Trying to write: %s entry", dataAfter.getType());
+        final Long natInstanceId = id.firstKeyOf(NatInstance.class).getId();
+        final Long mappingEntryId = id.firstKeyOf(MappingEntry.class).getIndex();
+        LOG.debug("Writing mapping entry: {} for nat-instance(vrf): {}", natInstanceId, mappingEntryId);
+
+        final SnatAddStaticMapping request = getRequest(id, dataAfter, natInstanceId, true);
+        getReplyForWrite(jvppSnat.snatAddStaticMapping(request).toCompletableFuture(), id);
+
+        // Store context mapping only if not already present under the same exact mapping
+        synchronized (mappingEntryContext) {
+            if (shouldStoreContextMapping(natInstanceId, mappingEntryId, dataAfter, writeContext)) {
+                mappingEntryContext
+                        .addEntry(natInstanceId, mappingEntryId, dataAfter, writeContext.getMappingContext());
+            }
+        }
+        LOG.trace("Mapping entry: {} for nat-instance(vrf): {} written successfully", request.vrfId, id);
+    }
+
+    /**
+     * Check whether entry is already stored in context under the same index.
+     *
+     * @return true if it's not yet stored under same index, false otherwise.
+     */
+    private boolean shouldStoreContextMapping(final long natInstanceId, final long mappingEntryId,
+                                              final MappingEntry dataAfter,
+                                              final WriteContext writeCtx) {
+        if (!mappingEntryContext.containsEntry(natInstanceId, dataAfter, writeCtx.getMappingContext())) {
+            return true;
+        }
+
+        final Optional<Long> storedIndex =
+                mappingEntryContext.getStoredIndex(natInstanceId, dataAfter, writeCtx.getMappingContext());
+        if (!storedIndex.isPresent()) {
+            return true;
+        }
+
+        if (storedIndex.get() != mappingEntryId) {
+            return true;
+        }
+
+        return false;
+    }
+
+    @Override
+    public void updateCurrentAttributes(@Nonnull final InstanceIdentifier<MappingEntry> id,
+                                        @Nonnull final MappingEntry dataBefore,
+                                        @Nonnull final MappingEntry dataAfter,
+                                        @Nonnull final WriteContext writeContext) throws WriteFailedException {
+        throw new WriteFailedException.UpdateFailedException(id, dataBefore, dataAfter,
+                new UnsupportedOperationException("Mapping entry update not supported"));
+    }
+
+    @Override
+    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 MappingEntryKey mappingEntryKey = id.firstKeyOf(MappingEntry.class);
+        LOG.debug("Deleting mapping entry: {} for nat-instance(vrf): {}", natInstanceId, mappingEntryKey);
+
+        final SnatAddStaticMapping request = getRequest(id, dataBefore, natInstanceId, false);
+        getReplyForWrite(jvppSnat.snatAddStaticMapping(request).toCompletableFuture(), id);
+        mappingEntryContext.removeEntry(natInstanceId, dataBefore, writeContext.getMappingContext());
+        LOG.trace("Mapping entry: {} for nat-instance(vrf): {} deleted successfully", request.vrfId, id);
+    }
+
+    private SnatAddStaticMapping getRequest(final InstanceIdentifier<MappingEntry> id,
+                                            final MappingEntry dataAfter,
+                                            final Long natInstanceId,
+                                            final boolean isAdd)
+            throws WriteFailedException.CreateFailedException {
+        final SnatAddStaticMapping request = new SnatAddStaticMapping();
+        request.isAdd = isAdd
+                ? (byte) 1
+                : 0;
+        request.isIp4 = 1;
+        // VPP uses int, model long
+        request.vrfId = natInstanceId.intValue();
+
+        // Snat supports only ipv4 now
+        if (dataAfter.getInternalSrcAddress().getIpv4Address() == null) {
+            throw new WriteFailedException.CreateFailedException(id, dataAfter,
+                    new UnsupportedOperationException(
+                            String.format("No Ipv4 present for in address %s. Ipv6 not supported",
+                                    dataAfter.getInternalSrcAddress())));
+        }
+
+        request.addrOnly = 1;
+        request.localIpAddress =
+                ipv4AddressNoZoneToArray(dataAfter.getInternalSrcAddress().getIpv4Address().getValue());
+        request.externalIpAddress = ipv4AddressNoZoneToArray(dataAfter.getExternalSrcAddress().getValue());
+
+        Optional<Short> internalPortNumber = getPortNumber(id, dataAfter,
+                (entry) -> Optional.fromNullable(entry.getInternalSrcPort()).transform(PortNumber::getPortType));
+        Optional<Short> externalPortNumber = getPortNumber(id, dataAfter,
+                (entry) -> Optional.fromNullable(entry.getExternalSrcPort()).transform(PortNumber::getPortType));
+        if (internalPortNumber.isPresent() && externalPortNumber.isPresent()) {
+            request.addrOnly = 0;
+            request.localPort = internalPortNumber.get();
+            request.externalPort = externalPortNumber.get();
+        }
+        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();
+            } else {
+                throw new IllegalArgumentException(
+                        String.format("Only single port number supported. Submitted: %s for entry: %s",
+                                dataAfter.getInternalSrcPort(), id));
+            }
+        });
+    }
+
+    interface PortGetter {
+        Optional<PortType> getPortType(MappingEntry entry);
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/NatInstaceCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/NatInstaceCustomizer.java
new file mode 100644
index 000000000..3cc477dd0
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/NatInstaceCustomizer.java
@@ -0,0 +1,53 @@
+/*
+ * 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.honeycomb.nat.write;
+
+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.yangtools.yang.binding.InstanceIdentifier;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+final class NatInstaceCustomizer implements ListWriterCustomizer<NatInstance, NatInstanceKey> {
+
+    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)
+            throws WriteFailedException {
+        LOG.trace("Writing nat-instance: {}", id);
+    }
+
+    @Override
+    public void updateCurrentAttributes(@Nonnull final InstanceIdentifier<NatInstance> id,
+                                        @Nonnull final NatInstance dataBefore, @Nonnull final NatInstance dataAfter,
+                                        @Nonnull final WriteContext writeContext) throws WriteFailedException {
+        LOG.trace("Updating nat-instance: {}", id);
+    }
+
+    @Override
+    public void deleteCurrentAttributes(@Nonnull final InstanceIdentifier<NatInstance> id,
+                                        @Nonnull final NatInstance dataBefore, @Nonnull final WriteContext writeContext)
+            throws WriteFailedException {
+        LOG.trace("Deleting nat-instance: {}", id);
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/NatWriterFactory.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/NatWriterFactory.java
new file mode 100644
index 000000000..ecc886bf0
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/NatWriterFactory.java
@@ -0,0 +1,66 @@
+/*
+ * 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.honeycomb.nat.write;
+
+import com.google.common.collect.Sets;
+import com.google.inject.Inject;
+import io.fd.honeycomb.nat.util.MappingEntryContext;
+import io.fd.honeycomb.translate.impl.write.GenericListWriter;
+import io.fd.honeycomb.translate.write.WriterFactory;
+import io.fd.honeycomb.translate.write.registry.ModifiableWriterRegistryBuilder;
+import io.fd.vpp.jvpp.snat.future.FutureJVppSnatFacade;
+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.yangtools.yang.binding.InstanceIdentifier;
+
+/**
+ * Nat Writers registration.
+ */
+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 FutureJVppSnatFacade jvppSnat;
+    private final MappingEntryContext mappingEntryContext;
+
+    @Inject
+    public NatWriterFactory(final FutureJVppSnatFacade jvppSnat,
+                            final MappingEntryContext mappingEntryContext) {
+        this.jvppSnat = jvppSnat;
+        this.mappingEntryContext = mappingEntryContext;
+    }
+
+    @Override
+    public void init(@Nonnull final ModifiableWriterRegistryBuilder registry) {
+        // Nat-instance
+        registry.add(new GenericListWriter<>(NAT_INSTANCE_ID, new NatInstaceCustomizer()));
+        //  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(jvppSnat, mappingEntryContext)));
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/AbstractInterfaceNatCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/AbstractInterfaceNatCustomizer.java
new file mode 100644
index 000000000..64e714241
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/AbstractInterfaceNatCustomizer.java
@@ -0,0 +1,105 @@
+/*
+ * 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.honeycomb.nat.write.ifc;
+
+import io.fd.honeycomb.translate.spi.write.WriterCustomizer;
+import io.fd.honeycomb.translate.vpp.util.JvppReplyConsumer;
+import io.fd.honeycomb.translate.vpp.util.NamingContext;
+import io.fd.honeycomb.translate.write.WriteContext;
+import io.fd.honeycomb.translate.write.WriteFailedException;
+import io.fd.vpp.jvpp.snat.dto.SnatInterfaceAddDelFeature;
+import io.fd.vpp.jvpp.snat.dto.SnatInterfaceAddDelFeatureReply;
+import io.fd.vpp.jvpp.snat.future.FutureJVppSnatFacade;
+import java.util.concurrent.CompletionStage;
+import javax.annotation.Nonnull;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.Interface;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+import org.slf4j.Logger;
+
+abstract class AbstractInterfaceNatCustomizer<D extends DataObject> implements JvppReplyConsumer, WriterCustomizer<D> {
+
+    private final FutureJVppSnatFacade jvppSnat;
+    private final NamingContext ifcContext;
+
+    AbstractInterfaceNatCustomizer(@Nonnull final FutureJVppSnatFacade jvppSnat,
+                                   @Nonnull final NamingContext ifcContext) {
+        this.jvppSnat = jvppSnat;
+        this.ifcContext = ifcContext;
+    }
+
+    @Override
+    public void writeCurrentAttributes(@Nonnull final InstanceIdentifier<D> id, @Nonnull final D dataAfter,
+                                       @Nonnull final WriteContext writeContext) throws WriteFailedException {
+        final String ifcName = id.firstKeyOf(Interface.class).getName();
+        getLog().debug("Enabling " + getType() + " NAT on interface: {}", ifcName);
+        getLog().debug("Enabling " + getType() + " NAT: {}", id);
+
+        final int ifcIndex = ifcContext.getIndex(ifcName, writeContext.getMappingContext());
+        final SnatInterfaceAddDelFeature request = getRequest(ifcIndex, (byte)1);
+        final CompletionStage<SnatInterfaceAddDelFeatureReply> future = jvppSnat.snatInterfaceAddDelFeature(request);
+
+        final SnatInterfaceAddDelFeatureReply reply = getReplyForWrite(future.toCompletableFuture(), id);
+        getLog().debug("NAT " + getType() + " enabled successfully on: {}, reply: {}", ifcName, reply);
+    }
+
+    @Override
+    public void updateCurrentAttributes(@Nonnull final InstanceIdentifier<D> id,
+                                        @Nonnull final D dataBefore, @Nonnull final D dataAfter,
+                                        @Nonnull final WriteContext writeContext) throws WriteFailedException {
+        throw new WriteFailedException.UpdateFailedException(id, dataBefore, dataAfter,
+                new UnsupportedOperationException("Unable to update NAT feature"));
+    }
+
+    @Override
+    public void deleteCurrentAttributes(@Nonnull final InstanceIdentifier<D> id,
+                                        @Nonnull final D dataBefore, @Nonnull final WriteContext writeContext)
+            throws WriteFailedException {
+        final String ifcName = id.firstKeyOf(Interface.class).getName();
+        getLog().debug("Disabling " + getType() + " NAT on interface: {}", ifcName);
+        getLog().debug("Disabling " + getType() + " NAT: {}", id);
+
+        final int ifcIndex = ifcContext.getIndex(ifcName, writeContext.getMappingContext());
+        final SnatInterfaceAddDelFeature request = getRequest(ifcIndex, (byte)0);
+        final CompletionStage<SnatInterfaceAddDelFeatureReply> future = jvppSnat.snatInterfaceAddDelFeature(request);
+
+        final SnatInterfaceAddDelFeatureReply reply = getReplyForWrite(future.toCompletableFuture(), id);
+        getLog().debug("NAT " + getType() + " disabled successfully on: {}, reply: {}", ifcName, reply);
+    }
+
+    enum NatType {
+        INBOUND((byte)1), OUTBOUND((byte)0);
+
+        private final byte isInside;
+
+        NatType(final byte isInside) {
+            this.isInside = isInside;
+        }
+    }
+
+    abstract NatType getType();
+    abstract Logger getLog();
+
+    private SnatInterfaceAddDelFeature getRequest(final int ifcIdx, final byte isAdd) {
+        final SnatInterfaceAddDelFeature request = new SnatInterfaceAddDelFeature();
+        request.isAdd = isAdd;
+        request.isInside = getType().isInside;
+        request.swIfIndex = ifcIdx;
+        return request;
+    }
+
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/IfcNatWriterFactory.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/IfcNatWriterFactory.java
new file mode 100644
index 000000000..bf2c600a2
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/IfcNatWriterFactory.java
@@ -0,0 +1,62 @@
+/*
+ * 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.honeycomb.nat.write.ifc;
+
+import com.google.inject.Inject;
+import com.google.inject.name.Named;
+import io.fd.honeycomb.translate.impl.write.GenericWriter;
+import io.fd.honeycomb.translate.vpp.util.NamingContext;
+import io.fd.honeycomb.translate.write.WriterFactory;
+import io.fd.honeycomb.translate.write.registry.ModifiableWriterRegistryBuilder;
+import io.fd.vpp.jvpp.snat.future.FutureJVppSnatFacade;
+import javax.annotation.Nonnull;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.Interfaces;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.Interface;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214.NatInterfaceAugmentation;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.Nat;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.nat.Inbound;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.nat.Outbound;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+/**
+ * Nat Writers registration.
+ */
+public final class IfcNatWriterFactory implements WriterFactory {
+
+    private static final InstanceIdentifier<Interface>
+            IFC_ID = InstanceIdentifier.create(Interfaces.class).child(Interface.class);
+    private static final InstanceIdentifier<Nat> NAT_AUG_ID =
+            IFC_ID .augmentation(NatInterfaceAugmentation.class).child(Nat.class);
+
+    private final FutureJVppSnatFacade jvppSnat;
+    private final NamingContext ifcContext;
+
+    @Inject
+    public IfcNatWriterFactory(final FutureJVppSnatFacade jvppSnat,
+                               @Named("interface-context") final NamingContext ifcContext) {
+        this.jvppSnat = jvppSnat;
+        this.ifcContext = ifcContext;
+    }
+
+    @Override
+    public void init(@Nonnull final ModifiableWriterRegistryBuilder registry) {
+        registry.addAfter(new GenericWriter<>(NAT_AUG_ID.child(Inbound.class),
+                new InterfaceInboundNatCustomizer(jvppSnat, ifcContext)), IFC_ID);
+        registry.addAfter(new GenericWriter<>(NAT_AUG_ID.child(Outbound.class),
+                new InterfaceOutboundNatCustomizer(jvppSnat, ifcContext)), IFC_ID);
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/InterfaceInboundNatCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/InterfaceInboundNatCustomizer.java
new file mode 100644
index 000000000..8ab1c284c
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/InterfaceInboundNatCustomizer.java
@@ -0,0 +1,44 @@
+/*
+ * 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.honeycomb.nat.write.ifc;
+
+import io.fd.honeycomb.translate.vpp.util.NamingContext;
+import io.fd.vpp.jvpp.snat.future.FutureJVppSnatFacade;
+import javax.annotation.Nonnull;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.nat.Inbound;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+final class InterfaceInboundNatCustomizer extends AbstractInterfaceNatCustomizer<Inbound> {
+
+    private static final Logger LOG = LoggerFactory.getLogger(InterfaceInboundNatCustomizer.class);
+
+    InterfaceInboundNatCustomizer(@Nonnull final FutureJVppSnatFacade jvppSnat,
+                                         @Nonnull final NamingContext ifcContext) {
+        super(jvppSnat, ifcContext);
+    }
+
+    @Override
+    NatType getType() {
+        return NatType.INBOUND;
+    }
+
+    @Override
+    Logger getLog() {
+        return LOG;
+    }
+}
diff --git a/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/InterfaceOutboundNatCustomizer.java b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/InterfaceOutboundNatCustomizer.java
new file mode 100644
index 000000000..fdd174eba
--- /dev/null
+++ b/nat/nat2vpp/src/main/java/io/fd/honeycomb/nat/write/ifc/InterfaceOutboundNatCustomizer.java
@@ -0,0 +1,44 @@
+/*
+ * 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.honeycomb.nat.write.ifc;
+
+import io.fd.honeycomb.translate.vpp.util.NamingContext;
+import io.fd.vpp.jvpp.snat.future.FutureJVppSnatFacade;
+import javax.annotation.Nonnull;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang._interface.nat.rev161214._interface.nat.attributes.nat.Outbound;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+final class InterfaceOutboundNatCustomizer extends AbstractInterfaceNatCustomizer<Outbound> {
+
+    private static final Logger LOG = LoggerFactory.getLogger(InterfaceOutboundNatCustomizer.class);
+
+    InterfaceOutboundNatCustomizer(@Nonnull final FutureJVppSnatFacade jvppSnat,
+                                          @Nonnull final NamingContext ifcContext) {
+        super(jvppSnat, ifcContext);
+    }
+
+    @Override
+    NatType getType() {
+        return NatType.OUTBOUND;
+    }
+
+    @Override
+    Logger getLog() {
+        return LOG;
+    }
+}
diff --git a/nat/nat2vpp/src/test/java/io/fd/honeycomb/nat/NatModuleTest.java b/nat/nat2vpp/src/test/java/io/fd/honeycomb/nat/NatModuleTest.java
new file mode 100644
index 000000000..774dd6f2a
--- /dev/null
+++ b/nat/nat2vpp/src/test/java/io/fd/honeycomb/nat/NatModuleTest.java
@@ -0,0 +1,123 @@
+/*
+ * 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.honeycomb.nat;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.not;
+import static org.hamcrest.Matchers.empty;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.MockitoAnnotations.initMocks;
+
+import com.google.inject.Guice;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.multibindings.Multibinder;
+import com.google.inject.name.Named;
+import com.google.inject.testing.fieldbinder.Bind;
+import com.google.inject.testing.fieldbinder.BoundFieldModule;
+import io.fd.honeycomb.translate.read.ReaderFactory;
+import io.fd.honeycomb.translate.util.read.registry.CompositeReaderRegistryBuilder;
+import io.fd.honeycomb.translate.util.write.registry.FlatWriterRegistryBuilder;
+import io.fd.honeycomb.translate.vpp.util.NamingContext;
+import io.fd.honeycomb.translate.write.WriterFactory;
+import io.fd.vpp.jvpp.snat.future.FutureJVppSnatFacade;
+import java.util.HashSet;
+import java.util.Set;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mock;
+import org.opendaylight.controller.md.sal.binding.api.DataBroker;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.InterfacesState;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.InterfacesStateBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.state.Interface;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.state.InterfaceBuilder;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+public class NatModuleTest {
+
+    @Named("honeycomb-context")
+    @Bind
+    @Mock
+    private DataBroker honeycombContext;
+
+    @Bind
+    private ReaderFactory ietfIfcReaderFactory;
+
+    @Named("honeycomb-initializer")
+    @Bind
+    @Mock
+    private DataBroker honeycombInitializer;
+
+    @Named("interface-context")
+    @Bind
+    private NamingContext ifcContext;
+
+    @Inject
+    private Set<ReaderFactory> readerFactories = new HashSet<>();
+
+    @Inject
+    private Set<WriterFactory> writerFactories = new HashSet<>();
+
+    @Before
+    public void setUp() throws Exception {
+        ietfIfcReaderFactory = registry -> {
+            registry.addStructuralReader(InstanceIdentifier.create(InterfacesState.class), InterfacesStateBuilder.class);
+            registry.addStructuralReader(InstanceIdentifier.create(InterfacesState.class).child(Interface.class), InterfaceBuilder.class);
+        };
+        initMocks(this);
+        ifcContext = new NamingContext("interface-", "interface-context");
+        // Nat Module adds readers under InterfacesState/Interface and since readers for parents that do nothing need to
+        // be present, add structural readers (or add V3poModule here, but adding the full Module is not the best solution)
+        Guice.createInjector(binder -> Multibinder.newSetBinder(binder, ReaderFactory.class)
+                .addBinding().toInstance(registry -> {
+                    registry.addStructuralReader(InstanceIdentifier.create(InterfacesState.class),
+                            InterfacesStateBuilder.class);
+                    registry.addStructuralReader(InstanceIdentifier.create(InterfacesState.class).child(Interface.class),
+                            InterfaceBuilder.class);
+                }), new NatModule(MockJVppSnatProvider.class), BoundFieldModule.of(this)).injectMembers(this);
+    }
+
+    @Test
+    public void testReaderFactories() throws Exception {
+        assertThat(readerFactories, is(not(empty())));
+
+        // Test registration process (all dependencies present, topological order of readers does exist, etc.)
+        final CompositeReaderRegistryBuilder registryBuilder = new CompositeReaderRegistryBuilder();
+        readerFactories.forEach(factory -> factory.init(registryBuilder));
+        assertNotNull(registryBuilder.build());
+    }
+
+    @Test
+    public void testWriterFactories() throws Exception {
+        assertThat(writerFactories, is(not(empty())));
+
+        // Test registration process (all dependencies present, topological order of writers does exist, etc.)
+        final FlatWriterRegistryBuilder registryBuilder = new FlatWriterRegistryBuilder();
+        writerFactories.forEach(factory -> factory.init(registryBuilder));
+        assertNotNull(registryBuilder.build());
+    }
+
+    private static final class MockJVppSnatProvider implements Provider<FutureJVppSnatFacade> {
+
+        @Override
+        public FutureJVppSnatFacade get() {
+            return mock(FutureJVppSnatFacade.class);
+        }
+    }
+}
\ No newline at end of file
diff --git a/nat/nat2vpp/src/test/java/io/fd/honeycomb/nat/util/MappingEntryContextTest.java b/nat/nat2vpp/src/test/java/io/fd/honeycomb/nat/util/MappingEntryContextTest.java
new file mode 100644
index 000000000..fee8def89
--- /dev/null
+++ b/nat/nat2vpp/src/test/java/io/fd/honeycomb/nat/util/MappingEntryContextTest.java
@@ -0,0 +1,198 @@
+/*
+ * 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.honeycomb.nat.util;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertSame;
+import static org.mockito.Matchers.any;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+import static org.mockito.MockitoAnnotations.initMocks;
+
+import com.google.common.base.Optional;
+import com.google.common.collect.Lists;
+import io.fd.honeycomb.translate.MappingContext;
+import io.fd.honeycomb.translate.vpp.util.Ipv4Translator;
+import io.fd.vpp.jvpp.snat.dto.SnatStaticMappingDetails;
+import java.util.Collections;
+import java.util.List;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mock;
+import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.nat.context.rev161214.mapping.entry.context.attributes.nat.mapping.entry.context.nat.instance.MappingTableBuilder;
+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.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.MappingEntryBuilder;
+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.yangtools.yang.binding.InstanceIdentifier;
+
+@SuppressWarnings("unchecked")
+public class MappingEntryContextTest implements Ipv4Translator {
+
+    private MappingEntryContext ctx = new MappingEntryContext();
+    @Mock
+    private MappingContext mappingCtx;
+
+    @Before
+    public void setUp() throws Exception {
+        initMocks(this);
+    }
+
+    @Test
+    public void testAdd() throws Exception {
+        when(mappingCtx.read(any(InstanceIdentifier.class))).thenReturn(Optional.absent());
+        final long natId = 7;
+        final long entryId = 99;
+        final MappingEntry entry = getEntry(natId, "192.168.1.5", "17.14.4.6");
+
+        ctx.addEntry(natId, entryId, entry, mappingCtx);
+
+        verify(mappingCtx).put(MappingEntryContext.getId(natId, MappingEntryContext.entryToKey(entry)), MappingEntryContext.toCtxMapEntry(entry, entryId));
+    }
+
+    @Test
+    public void testRemove() throws Exception {
+        final long natId = 0;
+        final MappingEntry entry = getEntry(natId, "192.168.1.5", "17.14.4.6");
+
+        ctx.removeEntry(natId, entry, mappingCtx);
+
+        verify(mappingCtx).delete(MappingEntryContext.getId(natId, MappingEntryContext.entryToKey(entry)));
+    }
+
+    @Test
+    public void testGetExistingIndex() throws Exception {
+        final long natId = 0;
+        final long entryId = 12;
+        final MappingEntry entry = getEntry(entryId, "192.168.1.5", "17.14.4.6");
+        final SnatStaticMappingDetails details = getDetails(entryId, "192.168.1.5", "17.14.4.6");
+
+        when(mappingCtx.read(MappingEntryContext.getId(natId, MappingEntryContext.entryToKey(entry))))
+                .thenReturn(Optional.of(MappingEntryContext.toCtxMapEntry(entry, entryId)));
+
+        assertEquals(12, ctx.getStoredOrArtificialIndex(natId, details, mappingCtx));
+        verify(mappingCtx).read(MappingEntryContext.getId(natId, MappingEntryContext.entryToKey(entry)));
+    }
+
+    @Test
+    public void testFindDetails() throws Exception {
+        final long natId = 0;
+        final MappingEntry entry = getEntry(0, "192.168.1.5", "17.14.4.6");
+        final SnatStaticMappingDetails details = getDetails(0, "192.168.1.5", "17.14.4.6");
+        final MappingEntry entry2 = getEntry(1, "192.168.1.8", "17.14.4.10");
+        final SnatStaticMappingDetails details2 = getDetails(1, "192.168.1.8", "17.14.4.10");
+
+        final List<SnatStaticMappingDetails> someDetails = Lists.newArrayList(details, details2);
+
+        when(mappingCtx.read(MappingEntryContext.getTableId(natId)))
+                .thenReturn(Optional.of(new MappingTableBuilder()
+                        .setMappingEntry(Lists.newArrayList(
+                                MappingEntryContext.toCtxMapEntry(entry, 0),
+                                MappingEntryContext.toCtxMapEntry(entry2, 1)))
+                        .build()));
+
+        assertSame(details, ctx.findDetails(someDetails, natId, 0, mappingCtx));
+    }
+
+    @Test(expected = IllegalStateException.class)
+    public void testFindDetailsNoMappingStored() throws Exception {
+        final long natId = 0;
+        final long entryId = 12;
+        final SnatStaticMappingDetails details = getDetails(entryId, "192.168.1.5", "17.14.4.6");
+        final List<SnatStaticMappingDetails> someDetails = Lists.newArrayList(details);
+        when(mappingCtx.read(MappingEntryContext.getTableId(natId))).thenReturn(Optional.absent());
+
+        ctx.findDetails(someDetails, natId, entryId, mappingCtx);
+    }
+
+    @Test(expected = IllegalStateException.class)
+    public void testFindDetailsNoMappingStored2() throws Exception {
+        final long natId = 0;
+        final long entryId = 12;
+        final SnatStaticMappingDetails details = getDetails(entryId, "192.168.1.5", "17.14.4.6");
+        final List<SnatStaticMappingDetails> someDetails = Lists.newArrayList(details);
+
+        when(mappingCtx.read(MappingEntryContext.getTableId(natId)))
+                .thenReturn(Optional.of(new MappingTableBuilder().setMappingEntry(Collections.emptyList()).build()));
+
+        ctx.findDetails(someDetails, natId, entryId, mappingCtx);
+    }
+
+    @Test
+    public void testGetArtificialIndex() throws Exception {
+        final long natId = 0;
+        final long entryId = 0;
+        final MappingEntry entry = getEntry(entryId, "192.168.1.5", "17.14.4.6");
+        final long entryId2 = 55;
+        final MappingEntry entry2 = getEntry(entryId2, "192.168.1.6", "17.14.4.7");
+        final long entryId3 = 18954;
+        final MappingEntry entry3 = getEntry(entryId3, "192.168.1.7", "17.14.4.8");
+        final long entryId4 = 18955;
+        final MappingEntry entry4 = getEntry(entryId4, "192.168.1.8", "17.14.4.9");
+
+        final long newEntryId = 18956;
+        final MappingEntry newEntry = getEntry(newEntryId, "192.168.1.99", "17.14.4.99");
+        final SnatStaticMappingDetails newDetails = getDetails(newEntryId, "192.168.1.99", "17.14.4.99");
+        when(mappingCtx.read(MappingEntryContext.getId(natId, MappingEntryContext.entryToKey(newEntry))))
+                .thenReturn(Optional.absent());
+
+        when(mappingCtx.read(MappingEntryContext.getTableId(natId)))
+                .thenReturn(Optional.of(new MappingTableBuilder()
+                        .setMappingEntry(Lists.newArrayList(
+                                MappingEntryContext.toCtxMapEntry(entry, entryId),
+                                MappingEntryContext.toCtxMapEntry(entry3, entryId3),
+                                MappingEntryContext.toCtxMapEntry(entry4, entryId4),
+                                MappingEntryContext.toCtxMapEntry(entry2, entryId2)))
+                        .build()));
+
+        assertFalse(ctx.getStoredIndex(natId, newEntry, mappingCtx).isPresent());
+        assertEquals(newEntryId, ctx.getStoredOrArtificialIndex(natId, newDetails, mappingCtx));
+    }
+
+    private SnatStaticMappingDetails getDetails(final long vrfId, final String localIp, final String externIp) {
+        final SnatStaticMappingDetails snatStaticMappingDetails = new SnatStaticMappingDetails();
+        snatStaticMappingDetails.vrfId = (int) vrfId;
+        snatStaticMappingDetails.addrOnly = 1;
+        snatStaticMappingDetails.isIp4 = 1;
+        snatStaticMappingDetails.localIpAddress = ipv4AddressNoZoneToArray(localIp);
+        snatStaticMappingDetails.externalIpAddress = ipv4AddressNoZoneToArray(externIp);
+        return snatStaticMappingDetails;
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testAddExisting() throws Exception {
+        final long natId = 7;
+        final long entryId = 99;
+        final MappingEntry entry = getEntry(natId, "192.168.1.5", "17.14.4.6");
+        final org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.nat.context.rev161214.mapping.entry.context.attributes.nat.mapping.entry.context.nat.instance.mapping.table.MappingEntry
+                data = MappingEntryContext.toCtxMapEntry(entry, entryId);
+        when(mappingCtx.read(any(InstanceIdentifier.class))).thenReturn(Optional.of(data));
+
+        ctx.addEntry(natId, entryId, entry, mappingCtx);
+    }
+
+    private static MappingEntry getEntry(final long id, final String longernalIpv4, final String externalIpv4) {
+        return new MappingEntryBuilder()
+                .setKey(new MappingEntryKey(id))
+                .setType(org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.nat.rev150908.MappingEntry.Type.Static)
+                .setInternalSrcAddress(new IpAddress(new Ipv4Address(longernalIpv4)))
+                .setExternalSrcAddress(new Ipv4Address(externalIpv4))
+                .build();
+    }
+}
\ No newline at end of file
diff --git a/nat/nat2vpp/src/test/resources/nat.json b/nat/nat2vpp/src/test/resources/nat.json
new file mode 100644
index 000000000..c7d9afeb3
--- /dev/null
+++ b/nat/nat2vpp/src/test/resources/nat.json
@@ -0,0 +1,3 @@
+{
+  "enabled": "true"
+}
\ No newline at end of file