diff --git a/CHANGES.html b/CHANGES.html
index 1fa7fa16e..7c3f8fc55 100644
--- a/CHANGES.html
+++ b/CHANGES.html
@@ -74,6 +74,7 @@ us a note on ns-developers mailing list.</p>
 </ul>
 <h2>Changed behavior:</h2>
 <ul>
+<li>Wi-Fi: The default Wi-Fi standard is changed from 802.11a to 802.11ax, and the default rate control is changed from ArfWifiManager to IdealWifiManager.
 <li>Wi-Fi: EDCAFs (QosTxop objects) are no longer installed on non-QoS STAs and DCF (Txop object) is no longer installed on QoS STAs.</li>
 <li>Wi-Fi: Management frames (Probe Request/Response, Association Request/Response) are sent by QoS STAs according to the 802.11 specs.</li>
 <li>The <b>Frequency</b>, <b>ChannelNumber</b>, <b>ChannelWidth</b> and <b>Primary20MHzIndex</b>
diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index 0426f9e1b..9a4349b88 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -27,6 +27,9 @@ requirements (Note: not all ns-3 features are available on all systems):
 ### New user-visible features
 
 - (spectrum) ThreeGppSpectrumPropagationLossModel and ThreeGppChannelModel now support multiple PhasedArrayModel instances per device. This feature can be used to implement MIMO.
+- (wifi) The default Wi-Fi standard has been upgraded from 802.11a to 802.11ax.
+- (wifi) The default Wi-Fi rate control has been changed from ArfWifiManager to IdealWifiManager.
+
 ### Bugs fixed
 
 - (spectrum) Fix condition for channel matrix update in ThreeGppChannelModel (left and right operand were pointing to the same object)
diff --git a/doc/tutorial/source/building-topologies.rst b/doc/tutorial/source/building-topologies.rst
index 73e3cb835..770bdf5ba 100644
--- a/doc/tutorial/source/building-topologies.rst
+++ b/doc/tutorial/source/building-topologies.rst
@@ -958,41 +958,51 @@ wireless medium and can communicate and interfere:
 
   phy.SetChannel (channel.Create ());
 
-Once the PHY helper is configured, we can focus on the MAC layer. Here we choose to
-work with non-Qos MACs. WifiMacHelper object is used to set MAC parameters. 
+Once the PHY helper is configured, we can focus on the MAC layer. The
+WifiMacHelper object is used to set MAC parameters.
+The second statement below creates an 802.11 service set identifier (SSID)
+object that will be used to set the value of the "Ssid" ``Attribute`` of
+the MAC layer implementation.  
+
+
+::
+
+  WifiMacHelper mac;
+  Ssid ssid = Ssid ("ns-3-ssid");
+
+WifiHelper will, by default, configure
+the standard in use to be 802.11ax (known commercially as Wi-Fi 6) and configure
+a compatible rate control algorithm (IdealWifiManager).
 
 ::
 
   WifiHelper wifi;
-  wifi.SetRemoteStationManager ("ns3::AarfWifiManager");
 
-  WifiMacHelper mac;
-
-The ``SetRemoteStationManager`` method tells the helper the type of 
-rate control algorithm to use.  Here, it is asking the helper to use the AARF
-algorithm --- details are, of course, available in Doxygen.
-
-Next, we configure the type of MAC, the SSID of the infrastructure network we
-want to setup and make sure that our stations don't perform active probing:
+We are now ready to install Wi-Fi models on the nodes, using these four 
+helper objects (YansWifiChannelHelper, YansWifiPhyHelper, WifiMacHelper,
+WifiHelper) and the Ssid object created above.  These helpers have
+encapsulated a lot of default configuration,
+and can be further tailored using additional attribute configuration if
+desired.  We also will create NetDevice containers to store pointers to
+the WifiNetDevice objects that the helper create.
 
 ::
 
-  Ssid ssid = Ssid ("ns-3-ssid");
+  NetDeviceContainer staDevices
   mac.SetType ("ns3::StaWifiMac",
     "Ssid", SsidValue (ssid),
     "ActiveProbing", BooleanValue (false));
 
-This code first creates an 802.11 service set identifier (SSID) object
-that will be used to set the value of the "Ssid" ``Attribute`` of
-the MAC layer implementation.  The particular kind of MAC layer that
-will be created by the helper is specified by ``Attribute`` as
-being of the "ns3::StaWifiMac" type.  "QosSupported" ``Attribute`` is
-set to false by default for ``WifiMacHelper`` objects. The combination
+In the above code, the specific kind of MAC layer that
+will be created by the helper is specified by the TypeId value
+of `ns3::StaWifiMac` type.  The "QosSupported" attribute is
+set to true by default for ``WifiMacHelper`` objects when the standard
+is at least 802.11n or newer. The combination
 of these two configurations means that the MAC instance next created
-will be a non-QoS non-AP station (STA) in an infrastructure BSS (i.e.,
+will be a QoS-aware, non-AP station (STA) in an infrastructure BSS (i.e.,
 a BSS with an AP).  Finally, the "ActiveProbing" ``Attribute`` is
 set to false.  This means that probe requests will not be sent by MACs
-created by this helper.
+created by this helper, and stations will listen for AP beacons.
 
 Once all the station-specific parameters are fully configured, both at the
 MAC and PHY layers, we can invoke our now-familiar ``Install`` method to 
@@ -1015,9 +1025,7 @@ requirements of the AP.
 
 In this case, the ``WifiMacHelper`` is going to create MAC
 layers of the "ns3::ApWifiMac", the latter specifying that a MAC
-instance configured as an AP should be created. We do not change
-the default setting of "QosSupported" ``Attribute``, so it remains
-false - disabling 802.11e/WMM-style QoS support at created APs.  
+instance configured as an AP should be created.
 
 The next lines create the single AP which shares the same set of PHY-level
 ``Attributes`` (and channel) as the stations:
diff --git a/examples/tutorial/third.cc b/examples/tutorial/third.cc
index 75eb3e7db..1f3a1fd6e 100644
--- a/examples/tutorial/third.cc
+++ b/examples/tutorial/third.cc
@@ -99,22 +99,20 @@ main (int argc, char *argv[])
   YansWifiPhyHelper phy;
   phy.SetChannel (channel.Create ());
 
-  WifiHelper wifi;
-  wifi.SetRemoteStationManager ("ns3::AarfWifiManager");
-
   WifiMacHelper mac;
   Ssid ssid = Ssid ("ns-3-ssid");
+
+  WifiHelper wifi;
+
+  NetDeviceContainer staDevices;
   mac.SetType ("ns3::StaWifiMac",
                "Ssid", SsidValue (ssid),
                "ActiveProbing", BooleanValue (false));
-
-  NetDeviceContainer staDevices;
   staDevices = wifi.Install (phy, mac, wifiStaNodes);
 
+  NetDeviceContainer apDevices;
   mac.SetType ("ns3::ApWifiMac",
                "Ssid", SsidValue (ssid));
-
-  NetDeviceContainer apDevices;
   apDevices = wifi.Install (phy, mac, wifiApNode);
 
   MobilityHelper mobility;
diff --git a/examples/tutorial/third.py b/examples/tutorial/third.py
index 77bae2e0a..eba206bd7 100644
--- a/examples/tutorial/third.py
+++ b/examples/tutorial/third.py
@@ -93,12 +93,11 @@ channel = ns.wifi.YansWifiChannelHelper.Default()
 phy = ns.wifi.YansWifiPhyHelper()
 phy.SetChannel(channel.Create())
 
-wifi = ns.wifi.WifiHelper()
-wifi.SetRemoteStationManager("ns3::AarfWifiManager")
-
 mac = ns.wifi.WifiMacHelper()
 ssid = ns.wifi.Ssid ("ns-3-ssid")
 
+wifi = ns.wifi.WifiHelper()
+
 mac.SetType ("ns3::StaWifiMac", "Ssid", ns.wifi.SsidValue(ssid), "ActiveProbing", ns.core.BooleanValue(False))
 staDevices = wifi.Install(phy, mac, wifiStaNodes)
 
diff --git a/examples/wireless/mixed-wired-wireless.cc b/examples/wireless/mixed-wired-wireless.cc
index 866a6273b..daba0be13 100644
--- a/examples/wireless/mixed-wired-wireless.cc
+++ b/examples/wireless/mixed-wired-wireless.cc
@@ -295,7 +295,6 @@ main (int argc, char *argv[])
       ss << i;
       ssidString += ss.str ();
       Ssid ssid = Ssid (ssidString);
-      wifiInfra.SetRemoteStationManager ("ns3::ArfWifiManager");
       // setup stas
       macInfra.SetType ("ns3::StaWifiMac",
                         "Ssid", SsidValue (ssid));
diff --git a/examples/wireless/mixed-wired-wireless.py b/examples/wireless/mixed-wired-wireless.py
index dc902c20e..cffe740f8 100644
--- a/examples/wireless/mixed-wired-wireless.py
+++ b/examples/wireless/mixed-wired-wireless.py
@@ -260,7 +260,6 @@ def main(argv):
         ssid = ns.wifi.Ssid('wifi-infra' + str(i))
         wifiInfra = ns.wifi.WifiHelper()
         wifiPhy.SetChannel(wifiChannel.Create())
-        wifiInfra.SetRemoteStationManager('ns3::ArfWifiManager')
         macInfra = ns.wifi.WifiMacHelper();
         macInfra.SetType("ns3::StaWifiMac",
                          "Ssid", ns.wifi.SsidValue(ssid))
diff --git a/examples/wireless/wifi-80211e-txop.cc b/examples/wireless/wifi-80211e-txop.cc
index 498b6e925..e4c4d2262 100644
--- a/examples/wireless/wifi-80211e-txop.cc
+++ b/examples/wireless/wifi-80211e-txop.cc
@@ -115,7 +115,8 @@ int main (int argc, char *argv[])
   phy.SetPcapDataLinkType (WifiPhyHelper::DLT_IEEE802_11_RADIO);
   phy.SetChannel (channel.Create ());
 
-  WifiHelper wifi; //the default standard of 802.11a will be selected by this helper since the program doesn't specify another one
+  WifiHelper wifi;
+  wifi.SetStandard (WIFI_STANDARD_80211a);
   wifi.SetRemoteStationManager ("ns3::IdealWifiManager");
   WifiMacHelper mac;
 
diff --git a/examples/wireless/wifi-ap.cc b/examples/wireless/wifi-ap.cc
index 3df8538f8..4cf0a7f28 100644
--- a/examples/wireless/wifi-ap.cc
+++ b/examples/wireless/wifi-ap.cc
@@ -140,7 +140,6 @@ int main (int argc, char *argv[])
   YansWifiChannelHelper wifiChannel = YansWifiChannelHelper::Default ();
   wifiPhy.SetChannel (wifiChannel.Create ());
   Ssid ssid = Ssid ("wifi-default");
-  wifi.SetRemoteStationManager ("ns3::ArfWifiManager");
   // setup stas.
   wifiMac.SetType ("ns3::StaWifiMac",
                    "ActiveProbing", BooleanValue (true),
diff --git a/examples/wireless/wifi-ap.py b/examples/wireless/wifi-ap.py
index 17d37af10..d2fc7f662 100644
--- a/examples/wireless/wifi-ap.py
+++ b/examples/wireless/wifi-ap.py
@@ -118,7 +118,6 @@ def main(argv):
     wifiPhy.SetChannel(wifiChannel.Create())
 
     ssid = ns.wifi.Ssid("wifi-default")
-    wifi.SetRemoteStationManager("ns3::ArfWifiManager")
     wifiMac = ns.wifi.WifiMacHelper()
 
     # setup stas.
diff --git a/examples/wireless/wifi-blockack.cc b/examples/wireless/wifi-blockack.cc
index 4cc9153ab..9cffb5011 100644
--- a/examples/wireless/wifi-blockack.cc
+++ b/examples/wireless/wifi-blockack.cc
@@ -19,7 +19,7 @@
  */
 
 /**
- * This is a simple example in order to show how 802.11e compressed block ack mechanism could be used.
+ * This is a simple example in order to show how 802.11n compressed block ack mechanism could be used.
  *
  * Network topology:
  *
@@ -78,9 +78,10 @@ int main (int argc, char * argv[])
   phy.SetChannel (channel.Create ());
 
   WifiHelper wifi;
+  wifi.SetStandard (WIFI_STANDARD_80211n);
   WifiMacHelper mac;
   /* disable fragmentation */
-  wifi.SetRemoteStationManager ("ns3::AarfWifiManager", "FragmentationThreshold", UintegerValue (2500));
+  wifi.SetRemoteStationManager ("ns3::IdealWifiManager", "FragmentationThreshold", UintegerValue (2500));
 
   Ssid ssid ("My-network");
 
diff --git a/src/aodv/test/aodv-regression.cc b/src/aodv/test/aodv-regression.cc
index 130ffba89..3e50ebc8d 100644
--- a/src/aodv/test/aodv-regression.cc
+++ b/src/aodv/test/aodv-regression.cc
@@ -173,6 +173,7 @@ ChainRegressionTest::CreateDevices ()
   // This test suite output was originally based on YansErrorRateModel
   wifiPhy.SetErrorRateModel ("ns3::YansErrorRateModel");
   WifiHelper wifi;
+  wifi.SetStandard (WIFI_STANDARD_80211a);
   wifi.SetRemoteStationManager ("ns3::ConstantRateWifiManager", "DataMode", StringValue ("OfdmRate6Mbps"), "RtsCtsThreshold", StringValue ("2200"));
   NetDeviceContainer devices = wifi.Install (wifiPhy, wifiMac, *m_nodes);
 
diff --git a/src/aodv/test/bug-772.cc b/src/aodv/test/bug-772.cc
index 72ee3c994..27a18d30f 100644
--- a/src/aodv/test/bug-772.cc
+++ b/src/aodv/test/bug-772.cc
@@ -136,6 +136,7 @@ Bug772ChainTest::CreateDevices ()
   wifiPhy.Set ("TxGain", DoubleValue (1.0)); //this configuration should go away in future revision to the test
   wifiPhy.Set ("RxGain", DoubleValue (1.0)); //this configuration should go away in future revision to the test
   WifiHelper wifi;
+  wifi.SetStandard (WIFI_STANDARD_80211a);
   wifi.SetRemoteStationManager ("ns3::ConstantRateWifiManager", "DataMode", StringValue ("OfdmRate6Mbps"), "RtsCtsThreshold", StringValue ("2200"), "MaxSlrc", UintegerValue (7));
   NetDeviceContainer devices = wifi.Install (wifiPhy, wifiMac, *m_nodes);
 
diff --git a/src/aodv/test/loopback.cc b/src/aodv/test/loopback.cc
index 3182274e7..096ba4f8c 100644
--- a/src/aodv/test/loopback.cc
+++ b/src/aodv/test/loopback.cc
@@ -134,6 +134,7 @@ LoopbackTestCase::DoRun ()
   YansWifiChannelHelper wifiChannel = YansWifiChannelHelper::Default ();
   wifiPhy.SetChannel (wifiChannel.Create ());
   WifiHelper wifi;
+  wifi.SetStandard (WIFI_STANDARD_80211a);
   wifi.SetRemoteStationManager ("ns3::ConstantRateWifiManager", "DataMode", StringValue ("OfdmRate6Mbps"), "RtsCtsThreshold", StringValue ("2200"));
   NetDeviceContainer devices = wifi.Install (wifiPhy, wifiMac, nodes);
 
diff --git a/src/flow-monitor/examples/wifi-olsr-flowmon.py b/src/flow-monitor/examples/wifi-olsr-flowmon.py
index 743cb4831..e3a6102c0 100644
--- a/src/flow-monitor/examples/wifi-olsr-flowmon.py
+++ b/src/flow-monitor/examples/wifi-olsr-flowmon.py
@@ -56,7 +56,6 @@ def main(argv):
     wifiChannel = ns.wifi.YansWifiChannelHelper.Default()
     wifiPhy.SetChannel(wifiChannel.Create())
     ssid = ns.wifi.Ssid("wifi-default")
-    wifi.SetRemoteStationManager("ns3::ArfWifiManager")
     wifiMac.SetType ("ns3::AdhocWifiMac",
                      "Ssid", ns.wifi.SsidValue(ssid))
 
diff --git a/src/netanim/examples/wireless-animation.cc b/src/netanim/examples/wireless-animation.cc
index b54b02e54..ef015bb64 100644
--- a/src/netanim/examples/wireless-animation.cc
+++ b/src/netanim/examples/wireless-animation.cc
@@ -55,7 +55,6 @@ main (int argc, char *argv[])
   phy.SetChannel (channel.Create ());
 
   WifiHelper wifi;
-  wifi.SetRemoteStationManager ("ns3::AarfWifiManager");
 
   WifiMacHelper mac;
   Ssid ssid = Ssid ("ns-3-ssid");
diff --git a/src/test/ns3wifi/wifi-ac-mapping-test-suite.cc b/src/test/ns3wifi/wifi-ac-mapping-test-suite.cc
index b94fd94e1..5495172c5 100644
--- a/src/test/ns3wifi/wifi-ac-mapping-test-suite.cc
+++ b/src/test/ns3wifi/wifi-ac-mapping-test-suite.cc
@@ -136,7 +136,6 @@ WifiAcMappingTest::DoRun (void)
   wifiPhy.SetChannel (wifiChannel.Create ());
 
   Ssid ssid = Ssid ("wifi-ac-mapping");
-  wifi.SetRemoteStationManager ("ns3::ArfWifiManager");
 
   // Setup the AP, which will be the source of traffic for this test
   NodeContainer ap;
diff --git a/src/wifi/doc/source/wifi-design.rst b/src/wifi/doc/source/wifi-design.rst
index ee1db0582..555134c86 100644
--- a/src/wifi/doc/source/wifi-design.rst
+++ b/src/wifi/doc/source/wifi-design.rst
@@ -1026,7 +1026,7 @@ The following rate control algorithms can be used by the MAC low layer:
 
 Algorithms found in real devices:
 
-* ``ArfWifiManager`` (default for ``WifiHelper``)
+* ``ArfWifiManager``
 * ``OnoeWifiManager``
 * ``ConstantRateWifiManager``
 * ``MinstrelWifiManager``
@@ -1034,7 +1034,7 @@ Algorithms found in real devices:
 
 Algorithms in literature:
 
-* ``IdealWifiManager``
+* ``IdealWifiManager``  (default for ``WifiHelper``)
 * ``AarfWifiManager`` [lacage2004aarfamrr]_
 * ``AmrrWifiManager`` [lacage2004aarfamrr]_
 * ``CaraWifiManager`` [kim2006cara]_
diff --git a/src/wifi/doc/source/wifi-user.rst b/src/wifi/doc/source/wifi-user.rst
index d4147bee1..58e6f906d 100644
--- a/src/wifi/doc/source/wifi-user.rst
+++ b/src/wifi/doc/source/wifi-user.rst
@@ -274,7 +274,7 @@ The following values for WifiStandard are defined in
   WIFI_STANDARD_80211ax
 
 By default, the WifiHelper (the typical use case for WifiPhy creation) will
-configure the WIFI_STANDARD_80211a standard by default.  Other values
+configure the WIFI_STANDARD_80211ax standard by default.  Other values
 for standards should be passed explicitly to the WifiHelper object.
 
 If user has not already configured ChannelSettings when SetStandard is called,
diff --git a/src/wifi/examples/wifi-phy-configuration.cc b/src/wifi/examples/wifi-phy-configuration.cc
index 472cd039d..930e5e3ed 100644
--- a/src/wifi/examples/wifi-phy-configuration.cc
+++ b/src/wifi/examples/wifi-phy-configuration.cc
@@ -112,7 +112,7 @@ int main (int argc, char *argv[])
     // i.e. without further channel number/width/frequency configuration
 
     case 1:
-      // By default, WifiHelper will use WIFI_STANDARD_80211a
+      wifi.SetStandard (WIFI_STANDARD_80211a);
       staDevice = wifi.Install (phy, macSta, wifiStaNode.Get (0));
       apDevice = wifi.Install (phy, macAp, wifiApNode.Get (0));
       phySta = GetYansWifiPhyPtr (staDevice);
@@ -179,6 +179,7 @@ int main (int argc, char *argv[])
       PrintAttributesIfEnabled (printAttributes);
       break;
     case 7:
+      // By default, WifiHelper will use WIFI_STANDARD_80211ax
       wifi.SetStandard (WIFI_STANDARD_80211ax);
       phy.Set ("ChannelSettings", StringValue ("{0, 0, BAND_2_4GHZ, 0}"));
       staDevice = wifi.Install (phy, macSta, wifiStaNode.Get (0));
diff --git a/src/wifi/helper/wifi-helper.cc b/src/wifi/helper/wifi-helper.cc
index 1a0f42bca..5ab8148e8 100644
--- a/src/wifi/helper/wifi-helper.cc
+++ b/src/wifi/helper/wifi-helper.cc
@@ -712,11 +712,11 @@ WifiHelper::~WifiHelper ()
 }
 
 WifiHelper::WifiHelper ()
-  : m_standard (WIFI_STANDARD_80211a),
+  : m_standard (WIFI_STANDARD_80211ax),
     m_selectQueueCallback (&SelectQueueByDSField),
     m_enableFlowControl (true)
 {
-  SetRemoteStationManager ("ns3::ArfWifiManager");
+  SetRemoteStationManager ("ns3::IdealWifiManager");
 }
 
 void
diff --git a/src/wifi/test/wifi-test.cc b/src/wifi/test/wifi-test.cc
index 9f9d21629..0a38ca92d 100644
--- a/src/wifi/test/wifi-test.cc
+++ b/src/wifi/test/wifi-test.cc
@@ -954,7 +954,8 @@ SetChannelFrequencyTest::DoRun ()
   {
     // case 1:
     WifiHelper wifi;
-    // By default, WifiHelper will use WIFI_PHY_STANDARD_80211a
+    wifi.SetStandard (WIFI_STANDARD_80211a);
+    wifi.SetRemoteStationManager ("ns3::ArfWifiManager");
     staDevice = wifi.Install (phy, macSta, wifiStaNode.Get (0));
     phySta = GetYansWifiPhyPtr (staDevice);
     // We expect channel 36, width 20, frequency 5180
@@ -1021,9 +1022,9 @@ SetChannelFrequencyTest::DoRun ()
   }
   {
     // case 7:
+    // By default, WifiHelper will use WIFI_PHY_STANDARD_80211ax
     WifiHelper wifi;
     wifi.SetRemoteStationManager ("ns3::IdealWifiManager");
-    wifi.SetStandard (WIFI_STANDARD_80211ax);
     phy.Set ("ChannelSettings", StringValue ("{0, 0, BAND_2_4GHZ, 0}"));
     staDevice = wifi.Install (phy, macSta, wifiStaNode.Get (0));
     phySta = GetYansWifiPhyPtr (staDevice);
@@ -1036,7 +1037,6 @@ SetChannelFrequencyTest::DoRun ()
     // case 8:
     WifiHelper wifi;
     wifi.SetRemoteStationManager ("ns3::IdealWifiManager");
-    wifi.SetStandard (WIFI_STANDARD_80211ax);
     staDevice = wifi.Install (phy, macSta, wifiStaNode.Get (0));
     phySta = GetYansWifiPhyPtr (staDevice);
     NS_TEST_ASSERT_MSG_EQ (phySta->GetChannelNumber (), 42, "802.11ax-5GHz configuration");
@@ -1047,7 +1047,6 @@ SetChannelFrequencyTest::DoRun ()
     // case 9:
     WifiHelper wifi;
     wifi.SetRemoteStationManager ("ns3::IdealWifiManager");
-    wifi.SetStandard (WIFI_STANDARD_80211ax);
     phy.Set ("ChannelSettings", StringValue ("{0, 0, BAND_6GHZ, 0}"));
     staDevice = wifi.Install (phy, macSta, wifiStaNode.Get (0));
     phySta = GetYansWifiPhyPtr (staDevice);