wifi: Support DSSS Parameter Set information element

src/wifi/model/ap-wifi-mac.cc

@@ -389,6 +389,18 @@ ApWifiMac::GetSupportedRates (void) const
   return rates;
 }
 
+DsssParameterSet
+ApWifiMac::GetDsssParameterSet (void) const
+{
+  DsssParameterSet dsssParameters;
+  if (m_dsssSupported)
+    {
+      dsssParameters.SetDsssSupported (1);
+      dsssParameters.SetCurrentChannel (m_phy->GetChannelNumber ());
+    }
+  return dsssParameters;
+}
+
 CapabilityInformation
 ApWifiMac::GetCapabilities (void) const
 {
@@ -502,6 +514,10 @@ ApWifiMac::SendProbeResp (Mac48Address to)
   probe.SetCapabilities (GetCapabilities ());
   m_stationManager->SetShortPreambleEnabled (GetShortPreambleEnabled ());
   m_stationManager->SetShortSlotTimeEnabled (GetShortSlotTimeEnabled ());
+  if (m_dsssSupported)
+    {
+      probe.SetDsssParameterSet (GetDsssParameterSet ());
+    }
   if (m_erpSupported)
     {
       probe.SetErpInformation (GetErpInformation ());
@@ -601,6 +617,10 @@ ApWifiMac::SendOneBeacon (void)
   beacon.SetCapabilities (GetCapabilities ());
   m_stationManager->SetShortPreambleEnabled (GetShortPreambleEnabled ());
   m_stationManager->SetShortSlotTimeEnabled (GetShortSlotTimeEnabled ());
+  if (m_dsssSupported)
+    {
+      beacon.SetDsssParameterSet (GetDsssParameterSet ());
+    }
   if (m_erpSupported)
     {
       beacon.SetErpInformation (GetErpInformation ());

src/wifi/model/ap-wifi-mac.h

@@ -30,6 +30,7 @@
 #include "vht-capabilities.h"
 #include "amsdu-subframe-header.h"
 #include "supported-rates.h"
+#include "dsss-parameter-set.h"
 #include "erp-information.h"
 #include "edca-parameter-set.h"
 #include "ns3/random-variable-stream.h"
@@ -228,6 +229,12 @@ private:
    * \return SupportedRates all rates that we support
    */
   SupportedRates GetSupportedRates (void) const;
+  /**
+   * Return the DSSS Parameter Set that we support.
+   *
+   * \return the DSSS Parameter Set that we support
+   */
+  DsssParameterSet GetDsssParameterSet (void) const;
   /**
    * Enable or disable beacon generation of the AP.
    *

src/wifi/model/dsss-parameter-set.cc

@@ -0,0 +1,116 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2016 Sébastien Deronne
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: Sébastien Deronne <sebastien.deronne@gmail.com>
+ */
+
+#include "dsss-parameter-set.h"
+#include "ns3/assert.h"
+#include "ns3/log.h"
+#include <cmath>
+
+namespace ns3 {
+
+NS_LOG_COMPONENT_DEFINE ("DsssParameterSet");
+
+DsssParameterSet::DsssParameterSet ()
+  : m_currentChannel (0),
+    m_dsssSupported (0)
+{
+}
+
+WifiInformationElementId
+DsssParameterSet::ElementId () const
+{
+  return IE_DS_PARAMETER_SET;
+}
+
+void
+DsssParameterSet::SetDsssSupported (uint8_t dsssSupported)
+{
+  m_dsssSupported = dsssSupported;
+}
+
+void
+DsssParameterSet::SetCurrentChannel (uint8_t currentChannel)
+{
+  m_currentChannel = currentChannel;
+}
+
+uint8_t
+DsssParameterSet::GetCurrentChannel (void) const
+{
+  return m_currentChannel;
+}
+
+uint8_t
+DsssParameterSet::GetInformationFieldSize () const
+{
+  NS_ASSERT (m_dsssSupported > 0);
+  return 1;
+}
+
+Buffer::Iterator
+DsssParameterSet::Serialize (Buffer::Iterator i) const
+{
+  if (m_dsssSupported < 1)
+    {
+      return i;
+    }
+  return WifiInformationElement::Serialize (i);
+}
+
+uint16_t
+DsssParameterSet::GetSerializedSize () const
+{
+  if (m_dsssSupported < 1)
+    {
+      return 0;
+    }
+  return WifiInformationElement::GetSerializedSize ();
+}
+
+void
+DsssParameterSet::SerializeInformationField (Buffer::Iterator start) const
+{
+  if (m_dsssSupported == 1)
+    {
+      start.WriteU8 (m_currentChannel);
+    }
+}
+
+uint8_t
+DsssParameterSet::DeserializeInformationField (Buffer::Iterator start, uint8_t length)
+{
+  Buffer::Iterator i = start;
+  m_currentChannel = i.ReadU8 ();
+  return length;
+}
+
+ATTRIBUTE_HELPER_CPP (DsssParameterSet);
+
+std::ostream & operator << (std::ostream &os, const DsssParameterSet &DsssParameterSet)
+{
+  return os;
+}
+
+std::istream &operator >> (std::istream &is, DsssParameterSet &DsssParameterSet)
+{
+  return is;
+}
+
+} //namespace ns3

src/wifi/model/dsss-parameter-set.h

@@ -0,0 +1,94 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2016 Sébastien Deronne
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: Sébastien Deronne <sebastien.deronne@gmail.com>
+ */
+
+#ifndef DSSS_PARAMETER_SET_H
+#define DSSS_PARAMETER_SET_H
+
+#include <stdint.h>
+#include <ostream>
+#include "ns3/buffer.h"
+#include "ns3/wifi-information-element.h"
+
+namespace ns3 {
+
+/**
+ * \brief The DSSS Parameter Set
+ * \ingroup wifi
+ *
+ * This class knows how to serialise and deserialise the DSSS Parameter Set.
+ */
+class DsssParameterSet : public WifiInformationElement
+{
+public:
+  DsssParameterSet ();
+  void SetDsssSupported (uint8_t DsssSupported);
+  
+  /**
+   * Set the Current Channel field in the DsssParameterSet information element.
+   *
+   * \param qosInfo the CurrentChannel field in the DsssParameterSet information element
+   */
+  void SetCurrentChannel (uint8_t currentChannel);
+  
+  /*
+   * Return the Current Channel field in the DsssParameterSet information element.
+   *
+   * \return the Current Channel field in the DsssParameterSet information element
+   */
+  uint8_t GetCurrentChannel (void) const;
+  
+  WifiInformationElementId ElementId () const;
+  uint8_t GetInformationFieldSize () const;
+  void SerializeInformationField (Buffer::Iterator start) const;
+  uint8_t DeserializeInformationField (Buffer::Iterator start, uint8_t length);
+    
+  /**
+   * This information element is a bit special in that it is only
+   * included if the STA does support DSSS. To support this we
+   * override the Serialize and GetSerializedSize methods of
+   * WifiInformationElement.
+   *
+   * \param start
+   *
+   * \return an iterator
+   */
+  Buffer::Iterator Serialize (Buffer::Iterator start) const;
+  /**
+   * Return the serialized size of this DSSS Parameter Set.
+   *
+   * \return the serialized size of this DSSS Parameter Set
+   */
+  uint16_t GetSerializedSize () const;
+
+private:
+  uint8_t m_currentChannel;
+
+  //This is used to decide whether this element should be added to the frame or not
+  bool m_dsssSupported;
+};
+
+std::ostream &operator << (std::ostream &os, const DsssParameterSet &dsssParameterSet);
+std::istream &operator >> (std::istream &is, DsssParameterSet &dsssParameterSet);
+
+ATTRIBUTE_HELPER_HEADER (DsssParameterSet);
+
+} //namespace ns3
+
+#endif /* DSSS_PARAMETER_SET_H */

src/wifi/model/mgt-headers.cc

@@ -251,6 +251,18 @@ MgtProbeResponseHeader::SetSupportedRates (SupportedRates rates)
   m_rates = rates;
 }
 
+void
+MgtProbeResponseHeader::SetDsssParameterSet (DsssParameterSet dsssParameterSet)
+{
+  m_dsssParameterSet = dsssParameterSet;
+}
+
+DsssParameterSet
+MgtProbeResponseHeader::GetDsssParameterSet (void) const
+{
+  return m_dsssParameterSet;
+}
+
 void
 MgtProbeResponseHeader::SetErpInformation (ErpInformation erpInformation)
 {
@@ -301,7 +313,7 @@ MgtProbeResponseHeader::GetSerializedSize (void) const
   size += m_capability.GetSerializedSize ();
   size += m_ssid.GetSerializedSize ();
   size += m_rates.GetSerializedSize ();
-  //size += 3; //ds parameter set
+  size += m_dsssParameterSet.GetSerializedSize ();
   size += m_erpInformation.GetSerializedSize ();
   size += m_rates.extended.GetSerializedSize ();
   size += m_edcaParameterSet.GetSerializedSize ();
@@ -316,6 +328,7 @@ MgtProbeResponseHeader::Print (std::ostream &os) const
 {
   os << "ssid=" << m_ssid << ", "
      << "rates=" << m_rates << ", "
+     << "DSSS Parameter Set=" << m_dsssParameterSet << " , "
      << "ERP information=" << m_erpInformation << ", "
      << "HT Capabilities=" << m_htCapability << " , "
      << "HT Operations=" << m_htOperations << " , "
@@ -340,7 +353,7 @@ MgtProbeResponseHeader::Serialize (Buffer::Iterator start) const
   i = m_capability.Serialize (i);
   i = m_ssid.Serialize (i);
   i = m_rates.Serialize (i);
-  //i.WriteU8 (0, 3); //ds parameter set.
+  i = m_dsssParameterSet.Serialize (i);
   i = m_erpInformation.Serialize (i);
   i = m_rates.extended.Serialize (i);
   i = m_edcaParameterSet.Serialize (i);
@@ -359,7 +372,7 @@ MgtProbeResponseHeader::Deserialize (Buffer::Iterator start)
   i = m_capability.Deserialize (i);
   i = m_ssid.Deserialize (i);
   i = m_rates.Deserialize (i);
-  //i.Next (3); //ds parameter set
+  i = m_dsssParameterSet.DeserializeIfPresent (i);
   i = m_erpInformation.DeserializeIfPresent (i);
   i = m_rates.extended.DeserializeIfPresent (i);
   i = m_edcaParameterSet.DeserializeIfPresent (i);

src/wifi/model/mgt-headers.h

@@ -30,6 +30,7 @@
 #include "capability-information.h"
 #include "supported-rates.h"
 #include "ssid.h"
+#include "dsss-parameter-set.h"
 #include "ht-capabilities.h"
 #include "ht-operations.h"
 #include "vht-capabilities.h"
@@ -387,6 +388,12 @@ public:
    * \return Capability information
    */
   CapabilityInformation GetCapabilities (void) const;
+  /**
+   * Return the DSSS Parameter Set.
+   *
+   * \return the DSSS Parameter Set
+   */
+  DsssParameterSet GetDsssParameterSet (void) const;
   /**
    * Return the HT capabilities.
    *
@@ -459,6 +466,12 @@ public:
    * \param rates the supported rates
    */
   void SetSupportedRates (SupportedRates rates);
+  /**
+   * Set the DSSS Parameter Set.
+   *
+   * \param dsssParameterSet the DSSS Parameter Set
+   */
+  void SetDsssParameterSet (DsssParameterSet dsssParameterSet);
   /**
    * Set the ERP information.
    *
@@ -496,6 +509,7 @@ private:
   uint64_t m_beaconInterval;           //!< Beacon interval
   SupportedRates m_rates;              //!< List of supported rates
   CapabilityInformation m_capability;  //!< Capability information
+  DsssParameterSet m_dsssParameterSet; //!< DSSS Parameter Set
   HtCapabilities m_htCapability;       //!< HT capabilities
   HtOperations m_htOperations;         //!< HT operations
   VhtCapabilities m_vhtCapability;     //!< VHT capabilities

src/wifi/model/regular-wifi-mac.cc

@@ -43,7 +43,7 @@ RegularWifiMac::RegularWifiMac () :
   m_htSupported (0),
   m_vhtSupported (0),
   m_erpSupported (0),
-  m_isDsssOnly (0)
+  m_dsssSupported (0)
 {
   NS_LOG_FUNCTION (this);
   m_rxMiddle = new MacRxMiddle ();
@@ -523,9 +523,26 @@ void
 RegularWifiMac::SetErpSupported (bool enable)
 {
   NS_LOG_FUNCTION (this);
+  if (enable)
+    {
+      SetDsssSupported (true);
+    }
   m_erpSupported = enable;
 }
 
+void
+RegularWifiMac::SetDsssSupported (bool enable)
+{
+  NS_LOG_FUNCTION (this);
+  m_dsssSupported = enable;
+}
+
+bool
+RegularWifiMac::GetDsssSupported () const
+{
+  return m_dsssSupported;
+}
+
 void
 RegularWifiMac::SetCtsToSelfSupported (bool enable)
 {
@@ -1108,9 +1125,9 @@ RegularWifiMac::FinishConfigureStandard (enum WifiPhyStandard standard)
       cwmax = 1023;
       break;
     case WIFI_PHY_STANDARD_80211b:
+      SetDsssSupported (true);
       cwmin = 31;
       cwmax = 1023;
-      m_isDsssOnly = true;
       break;
     default:
       NS_FATAL_ERROR ("Unsupported WifiPhyStandard in RegularWifiMac::FinishConfigureStandard ()");
@@ -1122,14 +1139,15 @@ RegularWifiMac::FinishConfigureStandard (enum WifiPhyStandard standard)
 void
 RegularWifiMac::ConfigureContentionWindow (uint32_t cwMin, uint32_t cwMax)
 {
+  bool isDsssOnly = m_dsssSupported && !m_erpSupported;
   //The special value of AC_BE_NQOS which exists in the Access
   //Category enumeration allows us to configure plain old DCF.
-  ConfigureDcf (m_dca, cwMin, cwMax, m_isDsssOnly, AC_BE_NQOS);
+  ConfigureDcf (m_dca, cwMin, cwMax, isDsssOnly, AC_BE_NQOS);
 
   //Now we configure the EDCA functions
   for (EdcaQueues::iterator i = m_edca.begin (); i != m_edca.end (); ++i)
   {
-    ConfigureDcf (i->second, cwMin, cwMax, m_isDsssOnly, i->first);
+    ConfigureDcf (i->second, cwMin, cwMax, isDsssOnly, i->first);
   }
 }
 

src/wifi/model/regular-wifi-mac.h

@@ -509,6 +509,24 @@ protected:
    * \return true if ERP is supported, false otherwise
    */
   bool GetErpSupported () const;
+  
+  /**
+   * This Boolean is set \c true iff this WifiMac is to model
+   * 802.11b. It is exposed through the attribute system.
+   */
+  bool m_dsssSupported;
+  /**
+   * Enable or disable DSSS support for the device.
+   *
+   * \param enable whether DSSS is supported
+   */
+  void SetDsssSupported (bool enable);
+  /**
+   * Return whether the device supports DSSS.
+   *
+   * \return true if DSSS is supported, false otherwise
+   */
+  bool GetDsssSupported () const;
 
 
 private:
@@ -561,7 +579,6 @@ private:
   TracedCallback<const WifiMacHeader &> m_txErrCallback;
   
   bool m_shortSlotTimeSupported;
-  bool m_isDsssOnly;
 };
 
 } //namespace ns3

src/wifi/wscript

@@ -78,6 +78,7 @@ def build(bld):
         'model/vht-capabilities.cc',
         'model/erp-information.cc',
         'model/ht-operations.cc',
+        'model/dsss-parameter-set.cc',
         'model/edca-parameter-set.cc',
         'helper/wifi-radio-energy-model-helper.cc',
         'helper/vht-wifi-mac-helper.cc',
@@ -181,6 +182,7 @@ def build(bld):
         'model/vht-capabilities.h',
         'model/erp-information.h',
         'model/ht-operations.h',
+        'model/dsss-parameter-set.h',
         'model/edca-parameter-set.h',
         'helper/wifi-radio-energy-model-helper.h',
         'helper/vht-wifi-mac-helper.h',