diff --git a/configuration.rst b/configuration.rst
index bf19316..b960105 100644
--- a/configuration.rst
+++ b/configuration.rst
@@ -1,35 +1,22 @@
 Feature and Configuration
 *************************
 
-Configuration Basics
-====================
+.. tip::
+    Trellis configurations are done through ONOS **network configuration** service (sometime referred as **netcfg**), **CLI** or **REST API**.
+    We encourage you to `learn more about ONOS network configuration service <https://wiki.onosproject.org/display/ONOS/The+Network+Configuration+Service>`_ before continue reading the following contents.
 
-Device Configuration
-====================
 
-Bridging and Unicast Routing
-============================
+.. toctree::
+    :maxdepth: 1
 
-Dual Homing
-===========
-
-External Connectivity
-=====================
-
-DHCP Relay
-==========
-
-Multicast
-=========
-
-VLAN Cross Connect
-==================
-
-AAA
-===
-
-Pseudowire
-==========
-
-MAC Security
-============
+    configuration/device-config
+    configuration/bridging-unicast
+    configuration/address-assignment
+    configuration/dual-homing
+    configuration/external-connectivity
+    configuration/route-service
+    configuration/multicast
+    configuration/xconnect
+    configuration/aaa
+    configuration/pseudowire
+    configuration/macsec
\ No newline at end of file