diff --git a/src/devices/mesh/mesh-wifi-interface-mac.cc b/src/devices/mesh/mesh-wifi-interface-mac.cc
index 351cb4d75..e5404cbaa 100644
--- a/src/devices/mesh/mesh-wifi-interface-mac.cc
+++ b/src/devices/mesh/mesh-wifi-interface-mac.cc
@@ -720,16 +720,6 @@ MeshWifiInterfaceMac::TxFailed (WifiMacHeader const &hdr)
 {
   m_txErrCallback (hdr);
 }
-void
-MeshWifiInterfaceMac::DoStart ()
-{
-  m_beaconDca->Start ();
-  for (Queues::iterator i = m_queues.begin (); i != m_queues.end (); i ++)
-  {
-    i->second->Start ();
-  }
-  WifiMac::DoStart ();
-}
 
 void 
 MeshWifiInterfaceMac::FinishConfigureStandard (enum WifiPhyStandard standard)
diff --git a/src/devices/mesh/mesh-wifi-interface-mac.h b/src/devices/mesh/mesh-wifi-interface-mac.h
index 5c74f3f5a..60bb5b0c5 100644
--- a/src/devices/mesh/mesh-wifi-interface-mac.h
+++ b/src/devices/mesh/mesh-wifi-interface-mac.h
@@ -179,8 +179,6 @@ private:
   bool GetBeaconGeneration () const;
   /// Real d-tor
   virtual void DoDispose ();
-  ///Initiator at t=0
-  void DoStart ();
 
 private:
   typedef std::map<AccessClass, Ptr<DcaTxop> > Queues;
diff --git a/src/devices/wifi/adhoc-wifi-mac.cc b/src/devices/wifi/adhoc-wifi-mac.cc
index 9f1fe354f..44af9e4d8 100644
--- a/src/devices/wifi/adhoc-wifi-mac.cc
+++ b/src/devices/wifi/adhoc-wifi-mac.cc
@@ -298,11 +298,4 @@ AdhocWifiMac::TxFailed (const WifiMacHeader &hdr)
 {
   m_txErrCallback (hdr);
 }
-void
-AdhocWifiMac::DoStart ()
-{
-  m_dca->Start ();
-  WifiMac::DoStart ();
-}
-
 } // namespace ns3
diff --git a/src/devices/wifi/adhoc-wifi-mac.h b/src/devices/wifi/adhoc-wifi-mac.h
index 66f4798d9..2da19ac70 100644
--- a/src/devices/wifi/adhoc-wifi-mac.h
+++ b/src/devices/wifi/adhoc-wifi-mac.h
@@ -82,7 +82,6 @@ public:
 private:
   // inherited from Object base class.
   virtual void DoDispose (void);
-  void DoStart ();
   /* invoked by the MacLows. */
   void ForwardUp (Ptr<Packet> packet, const WifiMacHeader *hdr);
   AdhocWifiMac (const AdhocWifiMac & ctor_arg);
diff --git a/src/devices/wifi/dca-txop.cc b/src/devices/wifi/dca-txop.cc
index 1e1e59453..eba746669 100644
--- a/src/devices/wifi/dca-txop.cc
+++ b/src/devices/wifi/dca-txop.cc
@@ -268,13 +268,6 @@ DcaTxop::Low (void)
   return m_low;
 }
 
-void
-DcaTxop::DoStart ()
-{
-  m_dcf->ResetCw ();
-  m_dcf->StartBackoffNow (m_rng->GetNext (0, m_dcf->GetCw ()));
-  ns3::Dcf::DoStart ();
-}
 bool
 DcaTxop::NeedRts (Ptr<const Packet> packet)
 {
diff --git a/src/devices/wifi/dca-txop.h b/src/devices/wifi/dca-txop.h
index 2a805dd07..370bd7c31 100644
--- a/src/devices/wifi/dca-txop.h
+++ b/src/devices/wifi/dca-txop.h
@@ -121,7 +121,7 @@ private:
 
   // Inherited from ns3::Object
   Ptr<MacLow> Low (void);
-  void DoStart ();
+
   /* dcf notifications forwarded here */
   bool NeedsAccess (void) const;
   void NotifyAccessGranted (void);
diff --git a/src/devices/wifi/edca-txop-n.cc b/src/devices/wifi/edca-txop-n.cc
index 43b002858..68b9f8db0 100644
--- a/src/devices/wifi/edca-txop-n.cc
+++ b/src/devices/wifi/edca-txop-n.cc
@@ -686,11 +686,5 @@ EdcaTxopN::SetMsduAggregator (Ptr<MsduAggregator> aggr)
 {
   m_aggregator = aggr;
 }
-void
-EdcaTxopN::DoStart ()
-{
-  m_dcf->ResetCw ();
-  m_dcf->StartBackoffNow (m_rng->GetNext (0, m_dcf->GetCw ()));
-  ns3::Dcf::DoStart ();
-}
+
 } //namespace ns3
diff --git a/src/devices/wifi/edca-txop-n.h b/src/devices/wifi/edca-txop-n.h
index 75759d9fa..298eb2700 100644
--- a/src/devices/wifi/edca-txop-n.h
+++ b/src/devices/wifi/edca-txop-n.h
@@ -132,7 +132,6 @@ public:
   void SetMsduAggregator (Ptr<MsduAggregator> aggr);
 
 private:
-  void DoStart ();
   /**
    * This functions are used only to correctly set addresses in a-msdu subframe.
    * If aggregating sta is a STA (in an infrastructured network):
diff --git a/src/devices/wifi/nqap-wifi-mac.cc b/src/devices/wifi/nqap-wifi-mac.cc
index c3e4bbd9b..437de6108 100644
--- a/src/devices/wifi/nqap-wifi-mac.cc
+++ b/src/devices/wifi/nqap-wifi-mac.cc
@@ -606,8 +606,6 @@ NqapWifiMac::DoStart (void)
     {
       m_beaconEvent = Simulator::ScheduleNow (&NqapWifiMac::SendOneBeacon, this);
     }
-  m_dca->Start ();
-  m_beaconDca->Start ();
   WifiMac::DoStart ();
 }
 
diff --git a/src/devices/wifi/nqsta-wifi-mac.cc b/src/devices/wifi/nqsta-wifi-mac.cc
index cae47eef7..571b6ebe4 100644
--- a/src/devices/wifi/nqsta-wifi-mac.cc
+++ b/src/devices/wifi/nqsta-wifi-mac.cc
@@ -686,10 +686,5 @@ NqstaWifiMac::FinishConfigureStandard (enum WifiPhyStandard standard)
       break;
     }
 }
-void
-NqstaWifiMac::DoStart ()
-{
-  m_dca->Start ();
-  WifiMac::DoStart ();
-}
+
 } // namespace ns3
diff --git a/src/devices/wifi/nqsta-wifi-mac.h b/src/devices/wifi/nqsta-wifi-mac.h
index 4c148c8dc..c20046a59 100644
--- a/src/devices/wifi/nqsta-wifi-mac.h
+++ b/src/devices/wifi/nqsta-wifi-mac.h
@@ -119,7 +119,6 @@ private:
     BEACON_MISSED,
     REFUSED
   };
-  void DoStart ();
   void SetBssid (Mac48Address bssid);
   void SetActiveProbing (bool enable);
   bool GetActiveProbing (void) const;
diff --git a/src/devices/wifi/qadhoc-wifi-mac.cc b/src/devices/wifi/qadhoc-wifi-mac.cc
index a4b32714d..a2bff3114 100644
--- a/src/devices/wifi/qadhoc-wifi-mac.cc
+++ b/src/devices/wifi/qadhoc-wifi-mac.cc
@@ -108,6 +108,10 @@ QadhocWifiMac::DoDispose (void)
   m_dcfManager = 0;
   m_low = 0;
   m_phy = 0;
+  m_voEdca = 0;
+  m_viEdca = 0;
+  m_beEdca = 0;
+  m_bkEdca = 0;
   m_stationManager = 0;
   for (Queues::iterator i = m_queues.begin (); i != m_queues.end (); ++i)
     {
@@ -441,14 +445,5 @@ QadhocWifiMac::FinishConfigureStandard (enum WifiPhyStandard standard)
       break;
     }
 }
-void
-QadhocWifiMac::DoStart ()
-{
-  for (Queues::iterator i = m_queues.begin (); i != m_queues.end (); ++i)
-    {
-      i->second->Start ();
-    }
-  WifiMac::DoStart ();
-}
 
 } //namespace ns3
diff --git a/src/devices/wifi/qadhoc-wifi-mac.h b/src/devices/wifi/qadhoc-wifi-mac.h
index 48859f21a..bf65b0299 100644
--- a/src/devices/wifi/qadhoc-wifi-mac.h
+++ b/src/devices/wifi/qadhoc-wifi-mac.h
@@ -78,7 +78,6 @@ public:
 private:
   Callback<void, Ptr<Packet>, Mac48Address, Mac48Address> m_forwardUp;
   virtual void DoDispose (void);
-  void DoStart ();
   void Receive (Ptr<Packet> packet, const WifiMacHeader *hdr);
   void ForwardUp (Ptr<Packet> packet, Mac48Address from, Mac48Address to);
   QadhocWifiMac &operator = (const QadhocWifiMac &);
@@ -102,6 +101,10 @@ private:
   Ptr<EdcaTxopN> GetBKQueue (void) const;
 
   Queues m_queues;
+  Ptr<EdcaTxopN> m_voEdca;
+  Ptr<EdcaTxopN> m_viEdca;
+  Ptr<EdcaTxopN> m_beEdca;
+  Ptr<EdcaTxopN> m_bkEdca;
   Ptr<MacLow> m_low;
   Ptr<WifiPhy> m_phy;
   Ptr<WifiRemoteStationManager> m_stationManager;
diff --git a/src/devices/wifi/qap-wifi-mac.cc b/src/devices/wifi/qap-wifi-mac.cc
index f0a42c66a..ec9a8d6f1 100644
--- a/src/devices/wifi/qap-wifi-mac.cc
+++ b/src/devices/wifi/qap-wifi-mac.cc
@@ -791,11 +791,6 @@ QapWifiMac::FinishConfigureStandard (enum WifiPhyStandard standard)
 void
 QapWifiMac::DoStart (void)
 {
-  m_beaconDca->Start ();
-  for (Queues::iterator i = m_queues.begin (); i != m_queues.end (); ++i)
-    {
-      i->second->Start ();
-    }
   m_beaconEvent.Cancel ();
   if (m_enableBeaconGeneration)
     {
diff --git a/src/devices/wifi/qsta-wifi-mac.cc b/src/devices/wifi/qsta-wifi-mac.cc
index 1b6c11c7f..1df061ed5 100644
--- a/src/devices/wifi/qsta-wifi-mac.cc
+++ b/src/devices/wifi/qsta-wifi-mac.cc
@@ -775,13 +775,5 @@ QstaWifiMac::FinishConfigureStandard (enum WifiPhyStandard standard)
     }
 }
 
-void
-QstaWifiMac::DoStart ()
-{
-  for (Queues::iterator i = m_queues.begin (); i != m_queues.end (); ++i)
-    {
-      i->second->Start ();
-    }
-  WifiMac::DoStart ();
-}
+
 }  //namespace ns3
diff --git a/src/devices/wifi/qsta-wifi-mac.h b/src/devices/wifi/qsta-wifi-mac.h
index 6c6fa2530..cc151f35b 100644
--- a/src/devices/wifi/qsta-wifi-mac.h
+++ b/src/devices/wifi/qsta-wifi-mac.h
@@ -87,7 +87,6 @@ public:
   void StartActiveAssociation (void);
 
 private:
-  void DoStart ();
   void SetBssid (Mac48Address bssid);
   Mac48Address GetBroadcastBssid (void);
   void Receive (Ptr<Packet> p, const WifiMacHeader *hdr);