diff --git a/core/trivial/src/main/java/org/onlab/onos/net/trivial/flow/impl/SimpleFlowRuleStore.java b/core/trivial/src/main/java/org/onlab/onos/net/trivial/flow/impl/SimpleFlowRuleStore.java
new file mode 100644
index 0000000..f839396
--- /dev/null
+++ b/core/trivial/src/main/java/org/onlab/onos/net/trivial/flow/impl/SimpleFlowRuleStore.java
@@ -0,0 +1,85 @@
+package org.onlab.onos.net.trivial.flow.impl;
+
+import org.onlab.onos.net.DeviceId;
+import org.onlab.onos.net.flow.DefaultFlowEntry;
+import org.onlab.onos.net.flow.FlowEntry;
+import org.onlab.onos.net.flow.FlowRule;
+import org.onlab.onos.net.flow.FlowRuleEvent;
+
+import com.google.common.collect.HashMultimap;
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Multimap;
+
+import static org.onlab.onos.net.flow.FlowRuleEvent.Type.*;
+
+/**
+ * Manages inventory of flow rules using trivial in-memory implementation.
+ */
+public class SimpleFlowRuleStore {
+
+    // store entries as a pile of rules, no info about device tables
+    private final Multimap<DeviceId, FlowEntry> flowEntries = HashMultimap.create();
+
+    /**
+     * Returns the flow entries associated with a device.
+     *
+     * @param deviceId the device ID
+     * @return the flow entries
+     */
+    Iterable<FlowEntry> getFlowEntries(DeviceId deviceId) {
+        return ImmutableSet.copyOf(flowEntries.get(deviceId));
+    }
+
+    /**
+     * Stores a new flow rule, and generates a FlowEntry for it.
+     *
+     * @param rule the flow rule to add
+     * @return a flow entry
+     */
+    FlowEntry storeFlowRule(FlowRule rule) {
+        DeviceId did = rule.deviceId();
+        FlowEntry entry = new DefaultFlowEntry(did,
+                rule.selector(), rule.treatment(), rule.priority());
+        flowEntries.put(did, entry);
+        return entry;
+    }
+
+    /**
+     * Stores a new flow rule, or updates an existing entry.
+     *
+     * @param rule the flow rule to add or update
+     * @return flow_added event, or null if just an update
+     */
+    FlowRuleEvent addOrUpdateFlowRule(FlowRule rule) {
+        DeviceId did = rule.deviceId();
+
+        // check if this new rule is an update to an existing entry
+        for (FlowEntry fe : flowEntries.get(did)) {
+            if (rule.equals(fe)) {
+                // TODO update the stats on this flowEntry?
+                return null;
+            }
+        }
+
+        FlowEntry newfe = new DefaultFlowEntry(did,
+                rule.selector(), rule.treatment(), rule.priority());
+        flowEntries.put(did, newfe);
+        return new FlowRuleEvent(RULE_ADDED, rule);
+    }
+
+    /**
+     *
+     * @param rule the flow rule to remove
+     * @return flow_removed event, or null if nothing removed
+     */
+    FlowRuleEvent removeFlowRule(FlowRule rule) {
+        synchronized (this) {
+            if (flowEntries.remove(rule.deviceId(), rule)) {
+                return new FlowRuleEvent(RULE_REMOVED, rule);
+            } else {
+                return null;
+            }
+        }
+    }
+
+}