diff --git a/plugins/mobility/highway-position-allocator.cc b/plugins/mobility/highway-position-allocator.cc
index 9ad52ba..03c9d27 100644
--- a/plugins/mobility/highway-position-allocator.cc
+++ b/plugins/mobility/highway-position-allocator.cc
@@ -55,13 +55,13 @@
   return tid;
 }
 
-HighwayPositionAllocator::HighwayPositionAllocator (){
-  m_previous_position = Vector(0.0, 0.0, 0.0);
+HighwayPositionAllocator::HighwayPositionAllocator ()
+  : m_previous_position (Vector (0.0, 0.0, 0.0))
+{
 }
 
 Vector HighwayPositionAllocator::GetNext (void) const{
-  UniformVariable random_gap_var (1.0, 10.0);
-  double random_gap = random_gap_var.GetValue();
+  double random_gap = m_random_gap_var.GetValue (1.0, 10.0);
   
   double delta_x = random_gap * cos(m_direction);
   double delta_y = random_gap * sin(m_direction);
@@ -100,4 +100,12 @@
   return m_length;
 }
 
+
+int64_t
+HighwayPositionAllocator::AssignStreams (int64_t stream)
+{
+  m_random_gap_var.SetStream (stream);
+  return 1;
+}
+
 }
diff --git a/plugins/mobility/highway-position-allocator.h b/plugins/mobility/highway-position-allocator.h
index 4028b4a..be0b219 100644
--- a/plugins/mobility/highway-position-allocator.h
+++ b/plugins/mobility/highway-position-allocator.h
@@ -42,11 +42,15 @@
   void SetLength(double length);
   double GetLength(void) const ;
 
+  virtual int64_t AssignStreams (int64_t stream);
+
 private:
   mutable Vector m_previous_position; // previously generated vehicle position
   Vector m_start; // highway starting point
   double m_direction; //highway direction
   double m_length; // highway length
+
+  mutable UniformRandomVariable m_random_gap_var;
 };
 }