diff --git a/specification.rst b/specification.rst
index 0e21a7b..f59ccc0 100644
--- a/specification.rst
+++ b/specification.rst
@@ -85,6 +85,8 @@
 - T3: Troubleshooting tool to diagnose broken forwarding paths fabric wide
 - ONOS-diags: One-click Diagnostics collection tool
 
+.. _Topology:
+
 Topology
 --------
 SD-Fabric can start at the smallest scale (single leaf) and grow horizontally.
@@ -94,35 +96,35 @@
 
 
 Single Leaf (ToR)
------------------
+^^^^^^^^^^^^^^^^^
 This is the minimum SD-Fabric setup. In this setup, all servers are connected to a single switch.
 
 .. image:: images/topology-single.png
   :width: 160px
 
 Single Leaf Pair (Dual-Homing)
-------------------------------
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Compared to single switch, it provides more redundancy in terms of server NIC failure and link failure.
 
 .. image:: images/topology-pair.png
   :width: 225px
 
 Leaf-Spine (without pairing)
-----------------------------
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Compared to single switch, it offers more redundancy in terms of switch failure and provides better scalability.
 
 .. image:: images/topology-2x2.png
   :width: 300px
 
 Leaf-Spine (with pairing)
--------------------------
+^^^^^^^^^^^^^^^^^^^^^^^^^
 It supports all the redundancy and scalability features mentioned above.
 
 .. image:: images/topology-2x4.png
   :width: 450px
 
 Multi-Stage Leaf-Spine
-----------------------
+^^^^^^^^^^^^^^^^^^^^^^
 Multi-stage is specifically designed for telco service providers.
 The first stage can be installed in the central office, while the second stage
 can be installed in a field office that is closer to the subscribers.