src/devices/wifi/amrr-wifi-manager.cc
changeset 2544 2e6e1a6e0d94
parent 2279 ff1d63db246d
child 2599 fcc1728eb669
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/devices/wifi/amrr-wifi-manager.cc	Mon Mar 03 04:03:39 2008 +0100
@@ -0,0 +1,290 @@
+/* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2003,2007 INRIA
+ *
+ * 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: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
+ */
+
+#include "amrr-wifi-manager.h"
+#include "ns3/simulator.h"
+#include "ns3/log.h"
+#include "ns3/uinteger.h"
+#include "ns3/double.h"
+
+NS_LOG_COMPONENT_DEFINE ("AmrrWifiRemoteStation");
+
+namespace ns3 {
+
+NS_OBJECT_ENSURE_REGISTERED (AmrrWifiManager);
+
+TypeId
+AmrrWifiManager::GetTypeId (void)
+{
+  static TypeId tid = TypeId ("AmrrWifiManager")
+    .SetParent<WifiRemoteStationManager> ()
+    .AddConstructor<AmrrWifiManager> ()
+    .AddAttribute ("UpdatePeriod",
+                   "The interval between decisions about rate control changes",
+                   Seconds (1.0),
+                   MakeTimeAccessor (&AmrrWifiManager::m_updatePeriod),
+                   MakeTimeChecker ())
+    .AddAttribute ("FailureRatio",
+                   "Ratio of minimum erronous transmissions needed to switch to a lower rate",
+                   Double (1.0/3.0),
+                   MakeDoubleAccessor (&AmrrWifiManager::m_failureRatio),
+                   MakeDoubleChecker (0.0, 1.0))
+    .AddAttribute ("SuccessRatio",
+                   "Ratio of maximum erronous transmissions needed to switch to a higher rate",
+                   Double (1.0/10.0),
+                   MakeDoubleAccessor (&AmrrWifiManager::m_successRatio),
+                   MakeDoubleChecker (0.0, 1.0))
+    .AddAttribute ("MaxSuccessThreshold",
+                   "Maximum number of consecutive success periods needed to switch to a higher rate",
+                   Uinteger (10),
+                   MakeUintegerAccessor (&AmrrWifiManager::m_maxSuccessThreshold),
+                   MakeUintegerChecker<uint32_t> ())
+    .AddAttribute ("MinSuccessThreshold",
+                   "Minimum number of consecutive success periods needed to switch to a higher rate",
+                   Uinteger (1),
+                   MakeUintegerAccessor (&AmrrWifiManager::m_minSuccessThreshold),
+                   MakeUintegerChecker<uint32_t> ())
+    ;
+  return tid;
+}
+
+AmrrWifiManager::AmrrWifiManager ()
+{}
+WifiRemoteStation *
+AmrrWifiManager::CreateStation (void)
+{
+  return new AmrrWifiRemoteStation (this);
+}
+
+AmrrWifiRemoteStation::AmrrWifiRemoteStation (Ptr<AmrrWifiManager> stations)
+  : m_stations (stations),
+    m_nextModeUpdate (Simulator::Now () + stations->m_updatePeriod),
+    m_tx_ok (0),
+    m_tx_err (0),
+    m_tx_retr (0),
+    m_retry (0),
+    m_txrate (0),
+    m_successThreshold (m_stations->m_minSuccessThreshold),
+    m_success (0),
+    m_recovery (false)
+{}
+AmrrWifiRemoteStation::~AmrrWifiRemoteStation ()
+{}
+
+void 
+AmrrWifiRemoteStation::ReportRxOk (double rxSnr, WifiMode txMode)
+{}
+void 
+AmrrWifiRemoteStation::ReportRtsFailed (void)
+{}
+void 
+AmrrWifiRemoteStation::ReportDataFailed (void)
+{
+  m_retry++;
+  m_tx_retr++;
+}
+void 
+AmrrWifiRemoteStation::ReportRtsOk (double ctsSnr, WifiMode ctsMode, double rtsSnr)
+{}
+void 
+AmrrWifiRemoteStation::ReportDataOk (double ackSnr, WifiMode ackMode, double dataSnr)
+{
+  m_retry = 0;
+  m_tx_ok++;
+}
+void 
+AmrrWifiRemoteStation::ReportFinalRtsFailed (void)
+{}
+void 
+AmrrWifiRemoteStation::ReportFinalDataFailed (void)
+{
+  m_retry = 0;
+  m_tx_err++;
+}
+bool
+AmrrWifiRemoteStation::IsMinRate (void) const
+{
+  return (m_txrate == 0);
+}
+bool
+AmrrWifiRemoteStation::IsMaxRate (void) const
+{
+  NS_ASSERT (m_txrate + 1 <= GetNSupportedModes ());
+  return (m_txrate + 1 == GetNSupportedModes ());
+}
+bool
+AmrrWifiRemoteStation::IsSuccess (void) const
+{
+  return (m_tx_retr + m_tx_err) < m_tx_ok * m_stations->m_successRatio;
+}
+bool
+AmrrWifiRemoteStation::IsFailure (void) const
+{
+  return (m_tx_retr + m_tx_err) > m_tx_ok * m_stations->m_failureRatio;
+}
+bool
+AmrrWifiRemoteStation::IsEnough (void) const
+{
+  return (m_tx_retr + m_tx_err + m_tx_ok) > 10;
+}
+void 
+AmrrWifiRemoteStation::ResetCnt (void)
+{
+  m_tx_ok = 0;
+  m_tx_err = 0;
+  m_tx_retr = 0;
+}
+void 
+AmrrWifiRemoteStation::IncreaseRate (void)
+{
+  m_txrate++;
+  NS_ASSERT (m_txrate < GetNSupportedModes ());
+}
+void 
+AmrrWifiRemoteStation::DecreaseRate (void)
+{
+  m_txrate--;
+}
+
+void
+AmrrWifiRemoteStation::UpdateMode (void)
+{
+  if (Simulator::Now () < m_nextModeUpdate)
+    {
+      return;
+    }
+  m_nextModeUpdate = Simulator::Now () + m_stations->m_updatePeriod;
+  NS_LOG_DEBUG ("Update");
+
+  bool needChange = false;
+
+  if (IsSuccess () && IsEnough ()) 
+    {
+      m_success++;
+      NS_LOG_DEBUG ("++ success="<<m_success<<" successThreshold="<<m_successThreshold<<
+                    " tx_ok="<<m_tx_ok<<" tx_err="<<m_tx_err<<" tx_retr="<<m_tx_retr<<
+                    " rate="<<m_txrate<<" n-supported-rates="<<GetNSupportedModes ());
+      if (m_success >= m_successThreshold &&
+          !IsMaxRate ()) 
+        {
+          m_recovery = true;
+          m_success = 0;
+          IncreaseRate ();
+          needChange = true;
+        } 
+      else 
+        {
+          m_recovery = false;
+        }
+    } 
+  else if (IsFailure ()) 
+    {
+      m_success = 0;
+      NS_LOG_DEBUG ("-- success="<<m_success<<" successThreshold="<<m_successThreshold<<
+                    " tx_ok="<<m_tx_ok<<" tx_err="<<m_tx_err<<" tx_retr="<<m_tx_retr<<
+                    " rate="<<m_txrate<<" n-supported-rates="<<GetNSupportedModes ());
+      if (!IsMinRate ()) 
+        {
+          if (m_recovery) 
+            {
+              m_successThreshold *= 2;
+              m_successThreshold = std::min (m_successThreshold,
+                                             m_stations->m_maxSuccessThreshold);
+            } 
+          else 
+            {
+              m_successThreshold = m_stations->m_minSuccessThreshold;
+            }
+          m_recovery = false;
+          DecreaseRate ();
+          needChange = true;
+        } 
+      else 
+        {
+          m_recovery = false;
+        }
+    }
+  if (IsEnough () || needChange) 
+    {
+      NS_LOG_DEBUG ("Reset");
+      ResetCnt ();
+    }
+}
+
+Ptr<WifiRemoteStationManager>
+AmrrWifiRemoteStation::GetManager (void) const
+{
+  return m_stations;
+}
+WifiMode 
+AmrrWifiRemoteStation::DoGetDataMode (uint32_t size)
+{
+  UpdateMode ();
+  NS_ASSERT (m_txrate < GetNSupportedModes ());
+  uint32_t rateIndex;
+  if (m_retry < 1)
+    {
+      rateIndex = m_txrate;
+    }
+  else if (m_retry < 2)
+    {
+      if (m_txrate > 0)
+        {
+          rateIndex = m_txrate - 1;
+        }
+      else
+        {
+          rateIndex = m_txrate;
+        }
+    }
+  else if (m_retry < 3)
+    {
+      if (m_txrate > 1)
+        {
+          rateIndex = m_txrate - 2;
+        }
+      else
+        {
+          rateIndex = m_txrate;
+        }
+    }
+  else
+    {
+      if (m_txrate > 2)
+        {
+          rateIndex = m_txrate - 3;
+        }
+      else
+        {
+          rateIndex = m_txrate;
+        }
+    }
+
+  return GetSupportedMode (rateIndex);
+}
+WifiMode 
+AmrrWifiRemoteStation::DoGetRtsMode (void)
+{
+  UpdateMode ();
+  // XXX: can we implement something smarter ?
+  return GetSupportedMode (0);
+}
+
+} // namespace ns3