VOL-3818: Initial version of OLT Topology discovery app; used to find active links between OLT NNI and Leaf switch ports.

Change-Id: I058b603d028446e8176821d85a25af8963e28924
diff --git a/api/src/main/java/org/opencord/olttopology/OltTopologyInformationService.java b/api/src/main/java/org/opencord/olttopology/OltTopologyInformationService.java
new file mode 100644
index 0000000..9ce5a0d
--- /dev/null
+++ b/api/src/main/java/org/opencord/olttopology/OltTopologyInformationService.java
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2016-present Open Networking Foundation
+ *
+ * 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.opencord.olttopology;
+
+
+import org.onosproject.net.ConnectPoint;
+
+import java.util.Map;
+
+/**
+ * Service for configuring the OLT topology collection and for
+ * viewing the topology information.
+ */
+public interface OltTopologyInformationService {
+
+    /**
+     * Get a collection of OLT ports and their neighbors.
+     *
+     * @return OLT Connect points and it's neighbors
+     */
+    Map<ConnectPoint, OltNeighborInfo> getNeighbours();
+
+    /**
+     * Provision Timer for sending LLDP packets to OLT NNI Ports.
+     *
+     * @param timer Periodicity in minutes for sending out LLDP packet to OLT NNI ports.
+     */
+    void lldpPeriodicity(int timer);
+}