wifi: Skip candidate AP if its channel width is not compatible with the non-AP STA

src/wifi/doc/source/wifi-user.rst

@@ -601,6 +601,10 @@ It is possible to configure the behavior of the association manager to either ab
 a problematic situation is detected (default) or to allow the association anyway, depending on the configured value
 for the ``ns3::WifiMac::AllowAssociationWithDifferentChannelWidth`` attribute.
 
+If the default association manager is used, it is also possible to skip candidate APs that are operating on a
+larger channel width than the non-AP STA and which would result in the problematic situation described above.
+This is done by setting the ``ns3::WifiMac::SkipCandidateAPsWithLargerChannelWidth`` attribute to true.
+
 
 SpectrumWifiPhyHelper
 =====================

src/wifi/model/wifi-default-assoc-manager.cc

@@ -13,6 +13,7 @@
 #include "wifi-net-device.h"
 #include "wifi-phy.h"
 
+#include "ns3/boolean.h"
 #include "ns3/log.h"
 #include "ns3/simulator.h"
 #include "ns3/vht-configuration.h"
@@ -40,7 +41,16 @@ WifiDefaultAssocManager::GetTypeId()
                           "notified within this amount of time, we give up setting up that link.",
                           TimeValue(MilliSeconds(5)),
                           MakeTimeAccessor(&WifiDefaultAssocManager::m_channelSwitchTimeout),
-                          MakeTimeChecker(Seconds(0)));
+                          MakeTimeChecker(Seconds(0)))
+            .AddAttribute(
+                "SkipAssocIncompatibleChannelWidth",
+                "If set to true, it does not include APs with incompatible channel width with the "
+                "STA in the list of candidate APs. An incompatible channel width is one that the "
+                "STA cannot advertise to the AP, unless AP operates on a channel width that is "
+                "equal or lower than that channel width.",
+                BooleanValue(false),
+                MakeBooleanAccessor(&WifiDefaultAssocManager::m_skipAssocIncompatibleChannelWidth),
+                MakeBooleanChecker());
     return tid;
 }
 
@@ -290,7 +300,8 @@ WifiDefaultAssocManager::ChannelSwitchTimeout(uint8_t linkId)
 bool
 WifiDefaultAssocManager::CanBeInserted(const StaWifiMac::ApInfo& apInfo) const
 {
-    return (m_waitBeaconEvent.IsPending() || m_probeRequestEvent.IsPending());
+    return ((m_waitBeaconEvent.IsPending() || m_probeRequestEvent.IsPending()) &&
+            (!m_skipAssocIncompatibleChannelWidth || IsChannelWidthCompatible(apInfo)));
 }
 
 bool

src/wifi/model/wifi-default-assoc-manager.h

@@ -57,9 +57,11 @@ class WifiDefaultAssocManager : public WifiAssocManager
      */
     void ChannelSwitchTimeout(uint8_t linkId);
 
-    EventId m_waitBeaconEvent;   ///< wait beacon event
-    EventId m_probeRequestEvent; ///< probe request event
-    Time m_channelSwitchTimeout; ///< maximum delay for channel switching
+    EventId m_waitBeaconEvent;                ///< wait beacon event
+    EventId m_probeRequestEvent;              ///< probe request event
+    Time m_channelSwitchTimeout;              ///< maximum delay for channel switching
+    bool m_skipAssocIncompatibleChannelWidth; ///< flag whether to skip APs with incompatible
+                                              ///< channel width
 
     /** Channel switch info */
     struct ChannelSwitchInfo