Я реализовал стандарт 802.11af в NS 3.29, но когда я имитировал с помощью wifi-tcp.cc, я заметил, что когда я использую скорость передачи данных 100 Мбит / с на прикладном уровне файла tcp, я получил пропущенный ack иПропускная способность 0 Мбит / с, даже если произошла повторная передача.С другой стороны, когда я изменил скорость передачи данных до 1 Мбит / с на прикладном уровне, я заметил, что у меня нет пропускной способности 0 Мбит / с, даже если пропущено подтверждение.Я хотел бы спросить, почему я не могу получить некоторую пропускную способность, даже если произошла повторная передача, и каковы возможные факторы, по которым я получил пропущенный акк.Пожалуйста, см. Ниже модифицированный код wifi-tcp.cc для справки.
С наилучшими пожеланиями, Адриан
/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
/*
* Copyright (c) 2015, IMDEA Networks Institute
*
* 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: Hany Assasa <hany.assasa@gmail.com>
.*
* This is a simple example to test TCP over 802.11n (with MPDU aggregation enabled).
*
* Network topology:
*
* Ap STA
* * *
* | |
* n1 n2
*
* In this example, an HT station sends TCP packets to the access point.
* We report the total throughput received during a window of 100ms.
* The user can specify the application data rate and choose the variant
* of TCP i.e. congestion control algorithm to use.
*/
#include "ns3/command-line.h"
#include "ns3/config.h"
#include "ns3/string.h"
#include "ns3/log.h"
#include "ns3/yans-wifi-helper.h"
#include "ns3/ssid.h"
#include "ns3/mobility-helper.h"
#include "ns3/on-off-helper.h"
#include "ns3/yans-wifi-channel.h"
#include "ns3/mobility-model.h"
#include "ns3/packet-sink.h"
#include "ns3/packet-sink-helper.h"
#include "ns3/tcp-westwood.h"
#include "ns3/internet-stack-helper.h"
#include "ns3/ipv4-address-helper.h"
#include "ns3/ipv4-global-routing-helper.h"
#include "ns3/animation-interface.h"
NS_LOG_COMPONENT_DEFINE ("wifi-tcp");
using namespace ns3;
Ptr<PacketSink> sink; /* Pointer to the packet sink application */
uint64_t lastTotalRx = 0; /* The value of the last total received bytes */
bool verbose = false;
void
CalculateThroughput ()
{
Time now = Simulator::Now (); /* Return the simulator's virtual time. */
double cur = (sink->GetTotalRx () - lastTotalRx) * (double) 8 / 1e5; /* Convert Application RX Packets to MBits. */
std::cout << now.GetSeconds () << "s: \t" << cur << " Mbit/s" << std::endl;
lastTotalRx = sink->GetTotalRx ();
Simulator::Schedule (MilliSeconds (100), &CalculateThroughput);
}
int
main (int argc, char *argv[])
{
uint32_t payloadSize = 1472; /* Transport layer payload size in bytes. */
std::string dataRate = "100Mbps"; /* Application layer datarate. */
std::string tcpVariant = "TcpNewReno"; /* TCP variant type. */
std::string phyRate = "TVhtMcs0"; /* Physical layer bitrate. */
double simulationTime = 10; /* Simulation time in seconds. */
bool pcapTracing = false; /* PCAP Tracing is enabled or not. */
/* Command line argument parser setup. */
CommandLine cmd;
cmd.AddValue ("payloadSize", "Payload size in bytes", payloadSize);
cmd.AddValue ("dataRate", "Application data ate", dataRate);
cmd.AddValue ("tcpVariant", "Transport protocol to use: TcpNewReno, "
"TcpHybla, TcpHighSpeed, TcpHtcp, TcpVegas, TcpScalable, TcpVeno, "
"TcpBic, TcpYeah, TcpIllinois, TcpWestwood, TcpWestwoodPlus, TcpLedbat ", tcpVariant);
cmd.AddValue ("phyRate", "Physical layer bitrate", phyRate);
cmd.AddValue ("simulationTime", "Simulation time in seconds", simulationTime);
cmd.AddValue ("pcap", "Enable/disable PCAP Tracing", pcapTracing);
cmd.AddValue ("verbose", "turn on all WifiNetDevice log components", verbose);
cmd.Parse (argc, argv);
tcpVariant = std::string ("ns3::") + tcpVariant;
// Select TCP variant
if (tcpVariant.compare ("ns3::TcpWestwoodPlus") == 0)
{
// TcpWestwoodPlus is not an actual TypeId name; we need TcpWestwood here
Config::SetDefault ("ns3::TcpL4Protocol::SocketType", TypeIdValue (TcpWestwood::GetTypeId ()));
// the default protocol type in ns3::TcpWestwood is WESTWOOD
Config::SetDefault ("ns3::TcpWestwood::ProtocolType", EnumValue (TcpWestwood::WESTWOODPLUS));
}
else
{
TypeId tcpTid;
NS_ABORT_MSG_UNLESS (TypeId::LookupByNameFailSafe (tcpVariant, &tcpTid), "TypeId " << tcpVariant << " not found");
Config::SetDefault ("ns3::TcpL4Protocol::SocketType", TypeIdValue (TypeId::LookupByName (tcpVariant)));
}
/* Configure TCP Options */
Config::SetDefault ("ns3::TcpSocket::SegmentSize", UintegerValue (payloadSize));
WifiMacHelper wifiMac;
WifiHelper wifiHelper;
if (verbose)
{
wifiHelper.EnableLogComponents (); // Turn on all Wifi logging
}
wifiHelper.SetStandard (WIFI_PHY_STANDARD_80211af);
/* Set up Legacy Channel */
YansWifiChannelHelper wifiChannel;
wifiChannel.SetPropagationDelay ("ns3::ConstantSpeedPropagationDelayModel");
wifiChannel.AddPropagationLoss ("ns3::FriisPropagationLossModel", "Frequency", DoubleValue (470e6));
//wifiChannel.AddPropagationLoss ("ns3::FixedRssLossModel", "Rss", DoubleValue (0));
/* Setup Physical Layer */
YansWifiPhyHelper wifiPhy = YansWifiPhyHelper::Default ();
wifiPhy.SetChannel (wifiChannel.Create ());
wifiPhy.Set ("TxPowerStart", DoubleValue (10.0));
wifiPhy.Set ("TxPowerEnd", DoubleValue (10.0));
wifiPhy.Set ("TxPowerLevels", UintegerValue (1));
wifiPhy.Set ("TxGain", DoubleValue (0));
wifiPhy.Set ("RxGain", DoubleValue (0));
wifiPhy.Set ("RxNoiseFigure", DoubleValue (10));
wifiPhy.Set ("CcaMode1Threshold", DoubleValue (-79));
wifiPhy.Set ("EnergyDetectionThreshold", DoubleValue (-79 + 3));
wifiPhy.SetErrorRateModel ("ns3::YansErrorRateModel");
wifiHelper.SetRemoteStationManager ("ns3::ConstantRateWifiManager",
"DataMode", StringValue (phyRate),
"ControlMode", StringValue ("TVhtMcs0"));
NodeContainer networkNodes;
networkNodes.Create (2);
Ptr<Node> apWifiNode = networkNodes.Get (0);
Ptr<Node> staWifiNode = networkNodes.Get (1);
/* Configure AP */
Ssid ssid = Ssid ("network");
wifiMac.SetType ("ns3::ApWifiMac",
"Ssid", SsidValue (ssid));
NetDeviceContainer apDevice;
apDevice = wifiHelper.Install (wifiPhy, wifiMac, apWifiNode);
/* Configure STA */
wifiMac.SetType ("ns3::StaWifiMac",
"Ssid", SsidValue (ssid));
NetDeviceContainer staDevices;
staDevices = wifiHelper.Install (wifiPhy, wifiMac, staWifiNode);
/* Mobility model */
MobilityHelper mobility;
Ptr<ListPositionAllocator> positionAlloc = CreateObject<ListPositionAllocator> ();
positionAlloc->Add (Vector (0.0, 0.0, 0.0));
positionAlloc->Add (Vector (1.0, 1.0, 0.0));
mobility.SetPositionAllocator (positionAlloc);
mobility.SetMobilityModel ("ns3::ConstantPositionMobilityModel");
mobility.Install (apWifiNode);
mobility.Install (staWifiNode);
/* Internet stack */
InternetStackHelper stack;
stack.Install (networkNodes);
Ipv4AddressHelper address;
address.SetBase ("10.0.0.0", "255.255.255.0");
Ipv4InterfaceContainer apInterface;
apInterface = address.Assign (apDevice);
Ipv4InterfaceContainer staInterface;
staInterface = address.Assign (staDevices);
/* Populate routing table */
Ipv4GlobalRoutingHelper::PopulateRoutingTables ();
/* Install TCP Receiver on the access point */
PacketSinkHelper sinkHelper ("ns3::TcpSocketFactory", InetSocketAddress (Ipv4Address::GetAny (), 9));
ApplicationContainer sinkApp = sinkHelper.Install (apWifiNode);
sink = StaticCast<PacketSink> (sinkApp.Get (0));
/* Install TCP/UDP Transmitter on the station */
OnOffHelper server ("ns3::TcpSocketFactory", (InetSocketAddress (apInterface.GetAddress (0), 9)));
server.SetAttribute ("PacketSize", UintegerValue (payloadSize));
server.SetAttribute ("OnTime", StringValue ("ns3::ConstantRandomVariable[Constant=1]"));
server.SetAttribute ("OffTime", StringValue ("ns3::ConstantRandomVariable[Constant=0]"));
server.SetAttribute ("DataRate", DataRateValue (DataRate (dataRate)));
ApplicationContainer serverApp = server.Install (staWifiNode);
/* Start Applications */
sinkApp.Start (Seconds (0.0));
serverApp.Start (Seconds (1.0));
Simulator::Schedule (Seconds (1.1), &CalculateThroughput);
AnimationInterface anim ("wireless-animationotin.xml");
/* Enable Traces */
if (pcapTracing)
{
wifiPhy.SetPcapDataLinkType (WifiPhyHelper::DLT_IEEE802_11_RADIO);
wifiPhy.EnablePcap ("AccessPoint", apDevice);
wifiPhy.EnablePcap ("Station", staDevices);
}
/* Start Simulation */
Simulator::Stop (Seconds (simulationTime + 1));
Simulator::Run ();
double averageThroughput = ((sink->GetTotalRx () * 8) / (1e6 * simulationTime));
Simulator::Destroy ();
/*if (averageThroughput < 50)
{
NS_LOG_ERROR ("Obtained throughput is not in the expected boundaries!");
exit (1);
}*/
std::cout << "\nAverage throughput: " << averageThroughput << " Mbit/s" << std::endl;
return 0;
}
