Added cubby-holes for new projects.
diff --git a/net/api/src/main/java/org/onlab/onos/net/flow/FlowRuleProviderService.java b/net/api/src/main/java/org/onlab/onos/net/flow/FlowRuleProviderService.java
new file mode 100644
index 0000000..9b26d76
--- /dev/null
+++ b/net/api/src/main/java/org/onlab/onos/net/flow/FlowRuleProviderService.java
@@ -0,0 +1,35 @@
+package org.onlab.onos.net.flow;
+
+import org.onlab.onos.net.ProviderService;
+
+/**
+ * Service through which flowrule providers can inject flowrule information into
+ * the core.
+ */
+public interface FlowRuleProviderService extends ProviderService {
+
+    /**
+     * Signals that a flow that was previously installed has been removed.
+     *
+     * @param flowDescription information about the removed flow
+     */
+    void flowRemoved(FlowDescription flowDescription);
+
+    /**
+     * Signals that a flowrule is missing for some network traffic.
+     *
+     * @param flowDescription information about traffic in need of flow rule(s)
+     */
+    void flowMissing(FlowDescription flowDescription);
+
+    /**
+     * Signals that a flowrule has been added.
+     *
+     * TODO  think about if this really makes sense, e.g. if stats collection or
+     * something can leverage it.
+     *
+     * @param flowDescription the rule that was added
+     */
+    void flowAdded(FlowDescription flowDescription);
+
+}