3
我使用NS3（v3.13）的Wi-Fi模式接收的吞吐量問題，配置如下（附模擬文件）：在基礎設施拓撲飽和交通
- 單AP（BSS）
- 多個STA （站）
- 應用持續時間= 10秒
- 飽和的下行鏈路業務（OnOffApplication與ONTIME = 2S和OFFTIME = 0）從AP到所有STA
- 物理層：802 .11a
- 默認YansWifiChannelHelper和YansWifiPhyHelper
- 速率控制：ConstantRateWifiManager
- 移動性：ConstantPositionMobilityModel（STA被定位在2個百米方圓周圍的AP圓）
雖然一切都進展順利，爲高比特率（飽和流量），當每個BSS的STA數量增加很多時，一些STA不會收到任何BYTE！
實驗：
- OnOffApplication DATARATE = 60MB/s的，物理層器件DataMode = OfdmRate Mbps和30個STA時，一個STA接收具有7.2MB/s的比特率和另一個與15.3MB包/ s的（所有其它的STA 28沒有收到任何BYTE）
- OnOffApplication DATARATE = 60MB/s的，DataMode = OfdmRate Mbps和30個STA時，一個STA接收具有的1.95MB /秒的比特率的數據包和另一個是4.3Mb/s（所有其他2 8 STA沒有收到任何字節）
我認爲問題來自OnOff應用程序配置;我應該如何配置它來模擬完整的緩衝區下行流量？
在此先感謝您的任何建議。
#include "ns3/core-module.h"
#include "ns3/point-to-point-module.h"
#include "ns3/network-module.h"
#include "ns3/applications-module.h"
#include "ns3/wifi-module.h"
#include "ns3/mobility-module.h"
#include "ns3/csma-module.h"
#include "ns3/internet-module.h"
#include "ns3/flow-monitor-helper.h"
#include "ns3/flow-monitor-module.h"
#include "ns3/applications-module.h"
#include "ns3/internet-module.h"
#include "ns3/gnuplot.h"
#include "ns3/constant-velocity-helper.h"
#include "ns3/integer.h"
#include "ns3/mpi-interface.h"
#include "math.h"
#include <iostream>
/**
* PARAMETERS
*/
#define StaNb 30
#define Distance 2
#define Duration 10
#define DataRate 90000000
#define PacketSize 1500
#define couleur(param) printf("\033[%sm",param)
using namespace ns3;
class Experiment {
public:
Experiment();
void CreateArchi(void);
void CreateApplis();
private:
Ptr<ListPositionAllocator> positionAllocAp;
Ptr<ListPositionAllocator> positionAllocSta;
Ptr<GridPositionAllocator> positionAllocStaCouloir;
Ptr<RandomDiscPositionAllocator> positionAllocStaAmphi;
std::vector<Ptr<ConstantPositionMobilityModel> > constant;
NodeContainer m_wifiAP, m_wifiQSta;
NetDeviceContainer m_APDevice;
NetDeviceContainer m_QStaDevice;
YansWifiChannelHelper m_channel;
Ptr<YansWifiChannel> channel;
YansWifiPhyHelper m_phyLayer_Sta, m_phyLayer_AP;
WifiHelper m_wifi;
QosWifiMacHelper m_macSta, m_macAP;
InternetStackHelper m_stack;
Ipv4InterfaceContainer m_StaInterface;
Ipv4InterfaceContainer m_ApInterface;
Ssid m_ssid;
};
Experiment::Experiment() {
positionAllocStaCouloir = CreateObject<GridPositionAllocator>();
positionAllocAp = CreateObject<ListPositionAllocator>();
positionAllocSta = CreateObject<ListPositionAllocator>();
positionAllocStaAmphi = CreateObject<RandomDiscPositionAllocator>();
m_wifi = WifiHelper::Default();
constant.resize(StaNb + 1);
for (int i = 0; i < StaNb + 1; i++) {
constant[i] = CreateObject<ConstantPositionMobilityModel>();
}
}
void Experiment::CreateArchi(void) {
m_wifiQSta.Create(StaNb);
m_wifiAP.Create(1);
m_ssid = Ssid("BSS_circle");
m_channel = YansWifiChannelHelper::Default();
channel = m_channel.Create();
m_wifi.SetStandard(WIFI_PHY_STANDARD_80211a);
m_wifi.SetRemoteStationManager("ns3::ConstantRateWifiManager", "DataMode",
StringValue("OfdmRate6Mbps"));
m_phyLayer_Sta = YansWifiPhyHelper::Default();
m_phyLayer_AP = YansWifiPhyHelper::Default();
m_phyLayer_Sta.SetChannel(channel);
m_phyLayer_AP.SetChannel(channel);
positionAllocAp->Add(Vector3D(0.0, 0.0, 0.0));
MobilityHelper mobilityAp;
mobilityAp.SetPositionAllocator(positionAllocAp);
mobilityAp.SetMobilityModel("ns3::ConstantPositionMobilityModel");
mobilityAp.Install(m_wifiAP.Get(0));
constant[0]->SetPosition(Vector3D(0.0, 0.0, 0.0));
float deltaAngle = 2 * M_PI/StaNb;
float angle = 0.0;
double x = 0.0;
double y = 0.0;
for (int i = 0; i < StaNb; i++) {
x = cos(angle) * Distance;
y = sin(angle) * Distance;
positionAllocSta->Add(Vector3D(x, y, 0.0));
MobilityHelper mobilitySta;
mobilitySta.SetPositionAllocator(positionAllocSta);
mobilitySta.SetMobilityModel("ns3::ConstantPositionMobilityModel");
mobilitySta.Install(m_wifiQSta.Get(i));
constant[i]->SetPosition(Vector3D(x, y, 0.0));
angle += deltaAngle;
}
m_macSta = QosWifiMacHelper::Default();
m_macSta.SetType("ns3::StaWifiMac", "ActiveProbing", BooleanValue(true),
"Ssid", SsidValue(m_ssid));
m_macAP = QosWifiMacHelper::Default();
m_macAP.SetType("ns3::ApWifiMac", "Ssid", SsidValue(m_ssid),
"BeaconInterval", TimeValue(Time(std::string("100ms"))));
m_APDevice.Add(m_wifi.Install(m_phyLayer_AP, m_macAP, m_wifiAP));
for (int i = 0; i < StaNb; i++) {
m_QStaDevice.Add(
m_wifi.Install(m_phyLayer_Sta, m_macSta, m_wifiQSta.Get(i)));
}
m_stack.Install(m_wifiAP);
m_stack.Install(m_wifiQSta);
Ipv4AddressHelper address;
address.SetBase("192.168.1.0", "255.255.255.0");
m_ApInterface.Add(address.Assign(m_APDevice.Get(0)));
for (int i = 0; i < StaNb; i++) {
m_StaInterface.Add(address.Assign(m_QStaDevice.Get(i)));
}
Ipv4GlobalRoutingHelper::PopulateRoutingTables();
}
void Experiment::CreateApplis() {
ApplicationContainer source;
OnOffHelper onoff("ns3::UdpSocketFactory", Address());
onoff.SetAttribute("OnTime", RandomVariableValue(ConstantVariable(2)));
onoff.SetAttribute("OffTime", RandomVariableValue(ConstantVariable(0)));
onoff.SetAttribute("DataRate", StringValue("500kb/s"));
for (int i = 0; i < StaNb; i++) {
AddressValue remoteAddress(
InetSocketAddress(m_StaInterface.GetAddress(i), 5010));
onoff.SetAttribute("Remote", remoteAddress);
source.Add(onoff.Install(m_wifiAP.Get(0)));
source.Start(Seconds(3.0));
source.Stop(Seconds(Duration));
}
ApplicationContainer sinks;
PacketSinkHelper packetSinkHelper("ns3::UdpSocketFactory",
Address(InetSocketAddress(Ipv4Address::GetAny(), 5010)));
for (int i = 0; i < StaNb; i++) {
sinks.Add(packetSinkHelper.Install(m_wifiQSta.Get(i)));
sinks.Start(Seconds(3.0));
sinks.Stop(Seconds(Duration));
}
}
int main(int argc, char *argv[]) {
Experiment exp = Experiment();
Config::SetDefault("ns3::WifiRemoteStationManager::RtsCtsThreshold",
StringValue("2346"));
exp.CreateArchi();
exp.CreateApplis();
FlowMonitorHelper flowmon;
Ptr<FlowMonitor> monitor = flowmon.InstallAll();
Simulator::Stop(Seconds(Duration));
Simulator::Run();
monitor->CheckForLostPackets();
Ptr<Ipv4FlowClassifier> classifier = DynamicCast<Ipv4FlowClassifier>(
flowmon.GetClassifier());
std::map<FlowId, FlowMonitor::FlowStats> stats = monitor->GetFlowStats();
int c = 0;
for (std::map<FlowId, FlowMonitor::FlowStats>::const_iterator i =
stats.begin(); i != stats.end(); ++i) {
Ipv4FlowClassifier::FiveTuple t = classifier->FindFlow(i->first);
std::cout << "Flux " << i->first << " (" << t.sourceAddress << " -> "
<< t.destinationAddress << ")\n";
std::cout << " Tx Bytes : " << i->second.txBytes << "\n";
std::cout << " Rx Bytes : " << i->second.rxBytes << "\n";
couleur("33");
std::cout << " Bitrate : "
<< i->second.rxBytes * 8.0
/(i->second.timeLastRxPacket.GetSeconds()
- i->second.timeFirstRxPacket.GetSeconds())
/1000000 << " Mbps\n\n";
couleur("0");
if (i->second.rxBytes > 0)
c++;
}
std::cout << " Number of receiving nodes : " << c << "\n";
Simulator::Destroy();
}