diff --git a/src/node/random-rectangle-topology.cc b/src/node/random-rectangle-topology.cc
index 05b3af74d..77efba294 100644
--- a/src/node/random-rectangle-topology.cc
+++ b/src/node/random-rectangle-topology.cc
@@ -18,58 +18,63 @@
  *
  * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
  */
-#include "random-rectangle-topology.h"
-#include "static-mobility-model.h"
 #include "ns3/random-variable-default-value.h"
+#include "random-rectangle-topology.h"
+#include "random-2d-position.h"
+#include "mobility-model.h"
 
 namespace ns3 {
 
-static RandomVariableDefaultValue 
-g_xVariable ("RandomRectangleTopologyX", 
-	     "Random variable to choose the x coordinate of the elements of a RandomRectangleTopology.",
-	     "Uniform:-100:100");
-static RandomVariableDefaultValue 
-g_yVariable ("RandomRectangleTopologyY", 
-	     "Random variable to choose the y coordinate of the elements of a RandomRectangleTopology.",
-	     "Uniform:-100:100");
+static ClassIdDefaultValue
+g_position ("Random2dTopologyType",
+            "The type of initial random position in a 2d topology.",
+            Random2dPosition::iid,
+            "Rectangle");
+
+static ClassIdDefaultValue
+g_mobility ("Random2dTopologyMobilityModelType",
+            "The type of mobility model attached to an object in a 2d topology.",
+            MobilityModel::iid,
+            "StaticMobilityModel");
 
 RandomRectangleTopology::RandomRectangleTopology ()
-  : m_xVariable (g_xVariable.GetCopy ()),
-    m_yVariable (g_yVariable.GetCopy ()),
-    m_positionModel (StaticMobilityModel::cid)
-{}
-
-RandomRectangleTopology::RandomRectangleTopology (double xMin, double xMax, double yMin, double yMax)
-  : m_xVariable (new UniformVariable (xMin, xMax)),
-    m_yVariable (new UniformVariable (yMin, yMax)),
-    m_positionModel (StaticMobilityModel::cid)
-{}
-RandomRectangleTopology::RandomRectangleTopology (const RandomVariable &xVariable, 
-						  const RandomVariable &yVariable)
-  : m_xVariable (xVariable.Copy ()),
-    m_yVariable (yVariable.Copy ()),
-    m_positionModel (StaticMobilityModel::cid)
+  : m_mobilityModel (g_mobility.GetValue ())
+{
+  m_positionModel = ComponentManager::Create<Random2dPosition> (g_position.GetValue (), 
+                                                                Random2dPosition::iid);
+}
+RandomRectangleTopology::RandomRectangleTopology (Ptr<Random2dPosition> positionModel, ClassId mobilityModel)
+  : m_positionModel (positionModel),
+    m_mobilityModel (mobilityModel)
 {}
 RandomRectangleTopology::~RandomRectangleTopology ()
 {
-  delete m_xVariable;
-  delete m_yVariable;
-  m_xVariable = 0;
-  m_yVariable = 0;
+  m_positionModel = 0;
 }
 
 void 
-RandomRectangleTopology::SetMobilityModelModel (ClassId classId)
+RandomRectangleTopology::SetMobilityModel (ClassId classId)
 {
-  m_positionModel = classId;
+  m_mobilityModel = classId;
+}
+
+void 
+RandomRectangleTopology::SetPositionModel (Ptr<Random2dPosition> positionModel)
+{
+  m_positionModel = positionModel;
 }
 
 void 
 RandomRectangleTopology::LayoutOne (Ptr<Object> object)
 {
-  double x = m_xVariable->GetValue ();
-  double y = m_yVariable->GetValue ();
-  object->AddInterface (ComponentManager::Create (m_positionModel, x, y));
+  Position2d position2d = m_positionModel->Get ();
+  Ptr<MobilityModel> mobility = ComponentManager::Create<MobilityModel> (m_mobilityModel, 
+                                                                         MobilityModel::iid);
+  Position position = mobility->Get ();
+  position.x = position2d.x;
+  position.y = position2d.y;
+  mobility->Set (position);
+  object->AddInterface (mobility);
 }
 
 
diff --git a/src/node/random-rectangle-topology.h b/src/node/random-rectangle-topology.h
index 7aa557ca2..4a5aa6621 100644
--- a/src/node/random-rectangle-topology.h
+++ b/src/node/random-rectangle-topology.h
@@ -21,33 +21,33 @@
 #ifndef RANDOM_RECTANGLE_TOPOLOGY_H
 #define RANDOM_RECTANGLE_TOPOLOGY_H
 
-#include "ns3/random-variable.h"
 #include "ns3/ptr.h"
 #include "ns3/object.h"
 #include "ns3/component-manager.h"
 
 namespace ns3 {
 
+class Random2dPosition;
+
 class RandomRectangleTopology
 {
  public:
-
   RandomRectangleTopology ();
-  RandomRectangleTopology (double xMin, double xMax, double yMin, double yMax);
-  RandomRectangleTopology (const RandomVariable &xVariable, const RandomVariable &yVariable);
+  RandomRectangleTopology (Ptr<Random2dPosition> positionModel,
+                           ClassId mobilityModel);
 
   ~RandomRectangleTopology ();
 
-  void SetMobilityModelModel (ClassId classId);
+  void SetMobilityModel (ClassId classId);
+  void SetPositionModel (Ptr<Random2dPosition> positionModel);
 
   void LayoutOne (Ptr<Object> object);
 
   template <typename T>
   void Layout (const T &begin, const T &end);
  private:
-  RandomVariable *m_xVariable;
-  RandomVariable *m_yVariable;
-  ClassId m_positionModel;
+  Ptr<Random2dPosition> m_positionModel;
+  ClassId m_mobilityModel;
 };
 
 } // namespace ns3