diff --git a/src/mobility/model/building.cc b/src/mobility/model/building.cc
index daa71c060..db5f4b12f 100644
--- a/src/mobility/model/building.cc
+++ b/src/mobility/model/building.cc
@@ -33,7 +33,9 @@ Building::Building (double _xMin, double _xMax,
           uint8_t _nFloors, uint8_t _nRoomX, uint8_t _nRoomY) :
      m_floor (_nFloors),
      m_roomX (_nRoomX),
-     m_roomY (_nRoomY)
+     m_roomY (_nRoomY),
+     m_buildingType (Residential),
+     m_externalWalls (ConcreteWithWindows)
      
 {
   m_buldingBounds = Box (_xMin, _xMax, _yMin, _yMax, _zMin, _zMax);
@@ -43,9 +45,23 @@ Building::Building (double _xMin, double _xMax,
 Building::Building () 
   : m_floor (0), 
     m_roomX (0), 
-    m_roomY (0)
+    m_roomY (0),
+    m_buildingType (Residential),
+    m_externalWalls (ConcreteWithWindows)
 {
   m_buldingBounds = Box ();
 }
 
+Building::BuildingType_t 
+Building::GetBuildingType ()
+{
+  return (m_buildingType);
+}
+
+Building::ExtWallsType_t
+Building::GetExtWallsType ()
+{
+  return (m_externalWalls);
+}
+
 } // namespace ns3
diff --git a/src/mobility/model/building.h b/src/mobility/model/building.h
index 122186327..adaa14499 100644
--- a/src/mobility/model/building.h
+++ b/src/mobility/model/building.h
@@ -40,6 +40,10 @@ public:
     {
       Residential, Office, Commercial
     };
+  enum ExtWallsType_t
+    {
+      Wood, ConcreteWithWindows, ConcreteWithoutWindows
+    };
   /**
   * \param _xMin x coordinates of left boundary.
   * \param _xMax x coordinates of right boundary.
@@ -64,6 +68,16 @@ public:
   */
   Building ();
   
+  /**
+  * Return the type of building (i.e., Residential, Office, Commercial)
+  */
+  BuildingType_t GetBuildingType ();
+  
+  /**
+  * Return the type of external walls (i.e., Wood, ConcreteWithWindows, ConcreteWithoutWindows)
+  */
+  ExtWallsType_t GetExtWallsType ();
+  
 private:
   Box m_buldingBounds;
   
@@ -72,6 +86,8 @@ private:
   uint8_t m_roomY;
   
   uint8_t m_buildingId;
+  BuildingType_t m_buildingType;
+  ExtWallsType_t m_externalWalls;
   
 };
 
diff --git a/src/propagation/model/buildings-propagation-loss-model.cc b/src/propagation/model/buildings-propagation-loss-model.cc
index 247661390..ca44ddb28 100644
--- a/src/propagation/model/buildings-propagation-loss-model.cc
+++ b/src/propagation/model/buildings-propagation-loss-model.cc
@@ -113,7 +113,7 @@ BuildingsPropagationLossModel::GetEnvironment (void) const
 
 
 double
-BuildingsPropagationLossModel::OkumuraHata (Ptr<MobilityModel> a, Ptr<MobilityModel> b) const
+BuildingsPropagationLossModel::OkumuraHata (Ptr<BuildingsMobilityModel> a, Ptr<BuildingsMobilityModel> b) const
 {
   // Hp: a is the rooftop antenna (from GetLoss logic)
   double loss = 0.0;
@@ -182,26 +182,80 @@ BuildingsPropagationLossModel::OkumuraHata (Ptr<MobilityModel> a, Ptr<MobilityMo
 
 
 double
-BuildingsPropagationLossModel::ItuR1411 (Ptr<MobilityModel> a, Ptr<MobilityModel> b) const
+BuildingsPropagationLossModel::ItuR1411 (Ptr<BuildingsMobilityModel> a, Ptr<BuildingsMobilityModel> b) const
 {
+  double dist = a->GetDistanceFrom (b);
+  double lossLow = 0.0;
+  double lossUp = 0.0;
+  double pi = 3.141592653589793;
+  double Lbp = 20*log10(m_lambda*m_lambda/(8*pi*a->GetPosition ().z*b->GetPosition ().z));
+  double Rbp = (4 * a->GetPosition ().z * b->GetPosition ().z) / m_lambda;
   
-  return (0.0);
+  if (dist <= Rbp)
+    {
+      lossLow = Lbp + 20*log10(dist/Rbp);
+      lossUp = Lbp + 20 + 25*log10(dist/Rbp);
+    }
+  else
+    {
+      lossLow = Lbp + 40*log10(dist/Rbp);
+      lossUp = Lbp + 20 + 40*log10(dist/Rbp);
+    }
+  
+  double loss = (lossUp + lossLow) / 2; // CHECK!!!
+  
+  return (loss);
 }
 
 
 double
-BuildingsPropagationLossModel::ItuR1238 (Ptr<MobilityModel> a, Ptr<MobilityModel> b) const
+BuildingsPropagationLossModel::ItuR1238 (Ptr<BuildingsMobilityModel> a, Ptr<BuildingsMobilityModel> b) const
 {
-
-  return (0.0);
+  double N = 0.0;
+  Ptr<Building> aBuilding = a->GetBuilding ();
+  if (aBuilding->GetBuildingType () == Building::Residential)
+    {
+      N = 28;
+    }
+  else if (aBuilding->GetBuildingType () == Building::Office)
+    {
+      N = 30;
+    }
+  else if (aBuilding->GetBuildingType () == Building::Commercial)
+    {
+      N = 22;
+    
+    }
+  else
+    {
+      NS_LOG_ERROR (this << " Unkwnon Wall Type");
+    }
+    
+  double loss = 20*log10(m_frequency) + N*log10(a->GetDistanceFrom (b)) - 28.0;
+  
+  return (loss);
 }
 
 
 double
-BuildingsPropagationLossModel::BEWPL (Ptr<MobilityModel> a) const
+BuildingsPropagationLossModel::BEWPL (Ptr<BuildingsMobilityModel> a) const
 {
-
-  return (0.0);
+  double loss = 0.0;
+  Ptr<Building> aBuilding = a->GetBuilding ();
+  if (aBuilding->GetExtWallsType () == Building::Wood)
+  {
+    loss = 4;
+  }
+  else if (aBuilding->GetExtWallsType () == Building::ConcreteWithWindows)
+  {
+    loss = 7;
+  }
+  else if (aBuilding->GetExtWallsType () == Building::ConcreteWithoutWindows)
+  {
+    loss = 10; // 10 ~ 20 dB
+  }
+    
+  return (loss);
 }
 
 
diff --git a/src/propagation/model/buildings-propagation-loss-model.h b/src/propagation/model/buildings-propagation-loss-model.h
index 78e14fff9..7199d8172 100644
--- a/src/propagation/model/buildings-propagation-loss-model.h
+++ b/src/propagation/model/buildings-propagation-loss-model.h
@@ -24,6 +24,8 @@
 
 #include "ns3/nstime.h"
 #include "ns3/propagation-loss-model.h"
+#include <ns3/building.h>
+#include <ns3/buildings-mobility-model.h>
 
 namespace ns3 {
 
@@ -82,10 +84,10 @@ public:
   
 private:
   virtual double DoCalcRxPower (double txPowerDbm, Ptr<MobilityModel> a, Ptr<MobilityModel> b) const;
-  double OkumuraHata (Ptr<MobilityModel> a, Ptr<MobilityModel> b) const;
-  double ItuR1411 (Ptr<MobilityModel> a, Ptr<MobilityModel> b) const;
-  double ItuR1238 (Ptr<MobilityModel> a, Ptr<MobilityModel> b) const;
-  double BEWPL (Ptr<MobilityModel> a) const;
+  double OkumuraHata (Ptr<BuildingsMobilityModel> a, Ptr<BuildingsMobilityModel> b) const;
+  double ItuR1411 (Ptr<BuildingsMobilityModel> a, Ptr<BuildingsMobilityModel> b) const;
+  double ItuR1238 (Ptr<BuildingsMobilityModel> a, Ptr<BuildingsMobilityModel> b) const;
+  double BEWPL (Ptr<BuildingsMobilityModel> a) const;
   
   double C;  // OH loss coefficient for the environment
   double N;  // ITU-R P.1238: power loss coefficient