diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/DefaultTransactionalMap.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/DefaultTransactionalMap.java
new file mode 100644
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--- /dev/null
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/DefaultTransactionalMap.java
@@ -0,0 +1,204 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.store.primitives.impl;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import org.onlab.util.HexString;
+import org.onosproject.store.service.ConsistentMap;
+import org.onosproject.store.service.DatabaseUpdate;
+import org.onosproject.store.service.Serializer;
+import org.onosproject.store.service.TransactionContext;
+import org.onosproject.store.service.TransactionalMap;
+import org.onosproject.store.service.Versioned;
+
+import static com.google.common.base.Preconditions.*;
+
+import com.google.common.base.Objects;
+import com.google.common.cache.CacheBuilder;
+import com.google.common.cache.CacheLoader;
+import com.google.common.cache.LoadingCache;
+import com.google.common.collect.Lists;
+import com.google.common.collect.Maps;
+import com.google.common.collect.Sets;
+
+/**
+ * Default Transactional Map implementation that provides a repeatable reads
+ * transaction isolation level.
+ *
+ * @param <K> key type
+ * @param <V> value type.
+ */
+public class DefaultTransactionalMap<K, V> implements TransactionalMap<K, V> {
+
+    private final TransactionContext txContext;
+    private static final String TX_CLOSED_ERROR = "Transaction is closed";
+    private final ConsistentMap<K, V> backingMap;
+    private final String name;
+    private final Serializer serializer;
+    private final Map<K, Versioned<V>> readCache = Maps.newConcurrentMap();
+    private final Map<K, V> writeCache = Maps.newConcurrentMap();
+    private final Set<K> deleteSet = Sets.newConcurrentHashSet();
+
+    private static final String ERROR_NULL_VALUE = "Null values are not allowed";
+    private static final String ERROR_NULL_KEY = "Null key is not allowed";
+
+    private final LoadingCache<K, String> keyCache = CacheBuilder.newBuilder()
+            .softValues()
+            .build(new CacheLoader<K, String>() {
+
+                @Override
+                public String load(K key) {
+                    return HexString.toHexString(serializer.encode(key));
+                }
+            });
+
+    protected K dK(String key) {
+        return serializer.decode(HexString.fromHexString(key));
+    }
+
+    public DefaultTransactionalMap(
+            String name,
+            ConsistentMap<K, V> backingMap,
+            TransactionContext txContext,
+            Serializer serializer) {
+        this.name = name;
+        this.backingMap = backingMap;
+        this.txContext = txContext;
+        this.serializer = serializer;
+    }
+
+    @Override
+    public V get(K key) {
+        checkState(txContext.isOpen(), TX_CLOSED_ERROR);
+        checkNotNull(key, ERROR_NULL_KEY);
+        if (deleteSet.contains(key)) {
+            return null;
+        }
+        V latest = writeCache.get(key);
+        if (latest != null) {
+            return latest;
+        } else {
+            Versioned<V> v = readCache.computeIfAbsent(key, k -> backingMap.get(k));
+            return v != null ? v.value() : null;
+        }
+    }
+
+    @Override
+    public V put(K key, V value) {
+        checkState(txContext.isOpen(), TX_CLOSED_ERROR);
+        checkNotNull(value, ERROR_NULL_VALUE);
+
+        V latest = get(key);
+        writeCache.put(key, value);
+        deleteSet.remove(key);
+        return latest;
+    }
+
+    @Override
+    public V remove(K key) {
+        checkState(txContext.isOpen(), TX_CLOSED_ERROR);
+        V latest = get(key);
+        if (latest != null) {
+            writeCache.remove(key);
+            deleteSet.add(key);
+        }
+        return latest;
+    }
+
+    @Override
+    public boolean remove(K key, V value) {
+        checkState(txContext.isOpen(), TX_CLOSED_ERROR);
+        checkNotNull(value, ERROR_NULL_VALUE);
+        V latest = get(key);
+        if (Objects.equal(value, latest)) {
+            remove(key);
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public boolean replace(K key, V oldValue, V newValue) {
+        checkState(txContext.isOpen(), TX_CLOSED_ERROR);
+        checkNotNull(oldValue, ERROR_NULL_VALUE);
+        checkNotNull(newValue, ERROR_NULL_VALUE);
+        V latest = get(key);
+        if (Objects.equal(oldValue, latest)) {
+            put(key, newValue);
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public V putIfAbsent(K key, V value) {
+        checkState(txContext.isOpen(), TX_CLOSED_ERROR);
+        checkNotNull(value, ERROR_NULL_VALUE);
+        V latest = get(key);
+        if (latest == null) {
+            put(key, value);
+        }
+        return latest;
+    }
+
+    protected List<DatabaseUpdate> prepareDatabaseUpdates() {
+        List<DatabaseUpdate> updates = Lists.newLinkedList();
+        deleteSet.forEach(key -> {
+            Versioned<V> original = readCache.get(key);
+            if (original != null) {
+                updates.add(DatabaseUpdate.newBuilder()
+                        .withMapName(name)
+                        .withType(DatabaseUpdate.Type.REMOVE_IF_VERSION_MATCH)
+                        .withKey(keyCache.getUnchecked(key))
+                        .withCurrentVersion(original.version())
+                        .build());
+            }
+        });
+        writeCache.forEach((key, value) -> {
+            Versioned<V> original = readCache.get(key);
+            if (original == null) {
+                updates.add(DatabaseUpdate.newBuilder()
+                        .withMapName(name)
+                        .withType(DatabaseUpdate.Type.PUT_IF_ABSENT)
+                        .withKey(keyCache.getUnchecked(key))
+                        .withValue(serializer.encode(value))
+                        .build());
+            } else {
+                updates.add(DatabaseUpdate.newBuilder()
+                        .withMapName(name)
+                        .withType(DatabaseUpdate.Type.PUT_IF_VERSION_MATCH)
+                        .withKey(keyCache.getUnchecked(key))
+                        .withCurrentVersion(original.version())
+                        .withValue(serializer.encode(value))
+                        .build());
+            }
+        });
+        return updates;
+    }
+
+    /**
+     * Discards all changes made to this transactional map.
+     */
+    protected void rollback() {
+        readCache.clear();
+        writeCache.clear();
+        deleteSet.clear();
+    }
+}
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