To implement resource allocation in Heterogeneous Networks (HetNets) in ns3, we need to simulate a scenario where different types of base stations (e.g., macro cells and small cells) coexist, and resources are allocated to users dynamically based on different algorithms. Below a detailed guide to implement this:
Steps for implementation
Step 1: Set up the simulation
- Download and install ns3 : Make sure that ns3 is installed in the computer. If not, install it from the official ns3 website.
- Familiarize yourself with ns3 basics : Understand the basics of ns3 such as creating nodes, setting up channels, and running basic simulations etc.
Step 2: Create the network topology
Define a network topology that involves macro cell base stations, small cell base stations, and user equipment (UE) nodes.
Create HetNet topology
#include “ns3/core-module.h”
#include “ns3/network-module.h”
#include “ns3/internet-module.h”
#include “ns3/point-to-point-module.h”
#include “ns3/lte-module.h”
#include “ns3/applications-module.h”
#include “ns3/mobility-module.h”
using namespace ns3;
NS_LOG_COMPONENT_DEFINE(“HetNetSimulation”);
int main(int argc, char *argv[])
{
CommandLine cmd;
cmd.Parse(argc, argv);
// Create nodes
NodeContainer ueNodes;
ueNodes.Create(10); // User equipment (UE) nodes
NodeContainer macroEnbNodes;
macroEnbNodes.Create(1); // Macro cell eNB (base station) node
NodeContainer smallEnbNodes;
smallEnbNodes.Create(3); // Small cell eNB (base station) nodes
// Set up LTE
Ptr<LteHelper> lteHelper = CreateObject<LteHelper>();
Ptr<PointToPointEpcHelper> epcHelper = CreateObject<PointToPointEpcHelper>();
lteHelper->SetEpcHelper(epcHelper);
Ptr<Node> pgw = epcHelper->GetPgwNode();
InternetStackHelper internet;
internet.Install(ueNodes);
// Set up mobility
MobilityHelper mobility;
mobility.SetPositionAllocator(“ns3::GridPositionAllocator”,
“MinX”, DoubleValue(0.0),
“MinY”, DoubleValue(0.0),
“DeltaX”, DoubleValue(50.0),
“DeltaY”, DoubleValue(50.0),
“GridWidth”, UintegerValue(3),
“LayoutType”, StringValue(“RowFirst”));
mobility.SetMobilityModel(“ns3::ConstantPositionMobilityModel”);
mobility.Install(macroEnbNodes);
mobility.SetMobilityModel(“ns3::ConstantPositionMobilityModel”);
mobility.Install(smallEnbNodes);
mobility.SetMobilityModel(“ns3::RandomWalk2dMobilityModel”,
“Bounds”, RectangleValue(Rectangle(-150, 150, -150, 150)));
mobility.Install(ueNodes);
// Install LTE devices to the nodes
NetDeviceContainer macroEnbLteDevs = lteHelper->InstallEnbDevice(macroEnbNodes);
NetDeviceContainer smallEnbLteDevs = lteHelper->InstallEnbDevice(smallEnbNodes);
NetDeviceContainer ueLteDevs = lteHelper->InstallUeDevice(ueNodes);
// Attach UEs to the macro eNB initially
for (uint32_t i = 0; i < ueNodes.GetN(); ++i)
{
lteHelper->Attach(ueLteDevs.Get(i), macroEnbLteDevs.Get(0));
}
// Assign IP addresses
Ipv4InterfaceContainer ueIpIface;
ueIpIface = epcHelper->AssignUeIpv4Address(NetDeviceContainer(ueLteDevs));
// Install and start applications on UEs and remote host
uint16_t dlPort = 1234;
ApplicationContainer clientApps, serverApps;
for (uint32_t i = 0; i < ueNodes.GetN(); ++i)
{
UdpClientHelper dlClient(ueIpIface.GetAddress(i), dlPort);
dlClient.SetAttribute(“Interval”, TimeValue(MilliSeconds(100)));
dlClient.SetAttribute(“MaxPackets”, UintegerValue(1000));
clientApps.Add(dlClient.Install(pgw));
UdpServerHelper dlServer(dlPort);
serverApps.Add(dlServer.Install(ueNodes.Get(i)));
}
serverApps.Start(Seconds(0.01));
clientApps.Start(Seconds(0.01));
// Enable tracing
lteHelper->EnableTraces();
Simulator::Run();
Simulator::Destroy();
return 0;
}
Step 3: Implement Resource Allocation Algorithms
Simulate dynamic resource allocation by implementing custom algorithms which adjust the attachment of UEs to eNBs based on different criteria like signal strength, load balancing, or QoS requirements.
Custom Resource Allocation
#include “ns3/lte-helper.h”
#include “ns3/lte-enb-net-device.h”
#include “ns3/lte-ue-net-device.h”
void DynamicResourceAllocation(Ptr<LteHelper> lteHelper, NetDeviceContainer ueLteDevs, NetDeviceContainer macroEnbLteDevs, NetDeviceContainer smallEnbLteDevs)
{
// Example: Attach UEs to the eNB with the strongest signal or least load
for (uint32_t i = 0; i < ueLteDevs.GetN(); ++i)
{
Ptr<LteUeNetDevice> ueDevice = ueLteDevs.Get(i)->GetObject<LteUeNetDevice>();
Ptr<Node> ueNode = ueDevice->GetNode();
Ptr<MobilityModel> ueMobility = ueNode->GetObject<MobilityModel>();
double maxSignalStrength = -std::numeric_limits<double>::infinity();
Ptr<NetDevice> bestEnbDevice = nullptr;
for (uint32_t j = 0; j < macroEnbLteDevs.GetN(); ++j)
{
Ptr<LteEnbNetDevice> enbDevice = macroEnbLteDevs.Get(j)->GetObject<LteEnbNetDevice>();
Ptr<Node> enbNode = enbDevice->GetNode();
Ptr<MobilityModel> enbMobility = enbNode->GetObject<MobilityModel>();
double distance = ueMobility->GetDistanceFrom(enbMobility);
double signalStrength = -distance; // Simplified signal strength based on distance
if (signalStrength > maxSignalStrength)
{
maxSignalStrength = signalStrength;
bestEnbDevice = enbDevice;
}
}
for (uint32_t j = 0; j < smallEnbLteDevs.GetN(); ++j)
{
Ptr<LteEnbNetDevice> enbDevice = smallEnbLteDevs.Get(j)->GetObject<LteEnbNetDevice>();
Ptr<Node> enbNode = enbDevice->GetNode();
Ptr<MobilityModel> enbMobility = enbNode->GetObject<MobilityModel>();
double distance = ueMobility->GetDistanceFrom(enbMobility);
double signalStrength = -distance; // Simplified signal strength based on distance
if (signalStrength > maxSignalStrength)
{
maxSignalStrength = signalStrength;
bestEnbDevice = enbDevice;
}
}
if (bestEnbDevice)
{
lteHelper->Attach(ueDevice, bestEnbDevice);
}
}
}
int main(int argc, char *argv[])
{
CommandLine cmd;
cmd.Parse(argc, argv);
// Create nodes
NodeContainer ueNodes;
ueNodes.Create(10); // User equipment (UE) nodes
NodeContainer macroEnbNodes;
macroEnbNodes.Create(1); // Macro cell eNB (base station) node
NodeContainer smallEnbNodes;
smallEnbNodes.Create(3); // Small cell eNB (base station) nodes
// Set up LTE
Ptr<LteHelper> lteHelper = CreateObject<LteHelper>();
Ptr<PointToPointEpcHelper> epcHelper = CreateObject<PointToPointEpcHelper>();
lteHelper->SetEpcHelper(epcHelper);
Ptr<Node> pgw = epcHelper->GetPgwNode();
InternetStackHelper internet;
internet.Install(ueNodes);
// Set up mobility
MobilityHelper mobility;
mobility.SetPositionAllocator(“ns3::GridPositionAllocator”,
“MinX”, DoubleValue(0.0),
“MinY”, DoubleValue(0.0),
“DeltaX”, DoubleValue(50.0),
“DeltaY”, DoubleValue(50.0),
“GridWidth”, UintegerValue(3),
“LayoutType”, StringValue(“RowFirst”));
mobility.SetMobilityModel(“ns3::ConstantPositionMobilityModel”);
mobility.Install(macroEnbNodes);
mobility.SetMobilityModel(“ns3::ConstantPositionMobilityModel”);
mobility.Install(smallEnbNodes);
mobility.SetMobilityModel(“ns3::RandomWalk2dMobilityModel”,
“Bounds”, RectangleValue(Rectangle(-150, 150, -150, 150)));
mobility.Install(ueNodes);
// Install LTE devices to the nodes
NetDeviceContainer macroEnbLteDevs = lteHelper->InstallEnbDevice(macroEnbNodes);
NetDeviceContainer smallEnbLteDevs = lteHelper->InstallEnbDevice(smallEnbNodes);
NetDeviceContainer ueLteDevs = lteHelper->InstallUeDevice(ueNodes);
// Attach UEs to the macro eNB initially
for (uint32_t i = 0; i < ueNodes.GetN(); ++i)
{
lteHelper->Attach(ueLteDevs.Get(i), macroEnbLteDevs.Get(0));
}
// Assign IP addresses
Ipv4InterfaceContainer ueIpIface;
ueIpIface = epcHelper->AssignUeIpv4Address(NetDeviceContainer(ueLteDevs));
// Install and start applications on UEs and remote host
uint16_t dlPort = 1234;
ApplicationContainer clientApps, serverApps;
for (uint32_t i = 0; i < ueNodes.GetN(); ++i)
{
UdpClientHelper dlClient(ueIpIface.GetAddress(i), dlPort);
dlClient.SetAttribute(“Interval”, TimeValue(MilliSeconds(100)));
dlClient.SetAttribute(“MaxPackets”, UintegerValue(1000));
clientApps.Add(dlClient.Install(pgw));
UdpServerHelper dlServer(dlPort);
serverApps.Add(dlServer.Install(ueNodes.Get(i)));
}
serverApps.Start(Seconds(0.01));
clientApps.Start(Seconds(0.01));
// Schedule dynamic resource allocation
Simulator::Schedule(Seconds(1.0), &DynamicResourceAllocation, lteHelper, ueLteDevs, macroEnbLteDevs, smallEnbLteDevs);
// Enable tracing
lteHelper->EnableTraces();
Simulator::Run();
Simulator::Destroy();
return 0;
}
Step 4: Configure Mobility
To simulate realistic scenarios where UEs can move, set up mobility model.
// Set up mobility
MobilityHelper mobility;
mobility.SetPositionAllocator(“ns3::GridPositionAllocator”,
“MinX”, DoubleValue(0.0),
“MinY”, DoubleValue(0.0),
“DeltaX”, DoubleValue(50.0),
“DeltaY”, DoubleValue(50.0),
“GridWidth”, UintegerValue(3),
“LayoutType”, StringValue(“RowFirst”));
mobility.SetMobilityModel(“ns3::ConstantPositionMobilityModel”);
mobility.Install(macroEnbNodes);
mobility.SetMobilityModel(“ns3::ConstantPositionMobilityModel”);
mobility.Install(smallEnbNodes);
mobility.SetMobilityModel(“ns3::RandomWalk2dMobilityModel”,
“Bounds”, RectangleValue(Rectangle(-150, 150, -150, 150)));
mobility.Install(ueNodes);
Step 5: Install and Configure Applications
On the nodes, install applications to generate and process network traffic.
// Install and start applications on UEs and remote host
uint16_t dlPort = 1234;
ApplicationContainer clientApps, serverApps;
for (uint32_t i = 0; i < ueNodes.GetN(); ++i)
{
UdpClientHelper dlClient(ueIpIface.GetAddress(i), dlPort);
dlClient.SetAttribute(“Interval”, TimeValue(MilliSeconds(100)));
dlClient.SetAttribute(“MaxPackets”, UintegerValue(1000));
clientApps.Add(dlClient.Install(pgw));
UdpServerHelper dlServer(dlPort);
serverApps.Add(dlServer.Install(ueNodes.Get(i)));
}
serverApps.Start(Seconds(0.01));
clientApps.Start(Seconds(0.01));
Step 6: Enable Tracing
To analyze the network performance, enable tracing.
// Enable tracing
lteHelper->EnableTraces();
Complete Example Code
Here is a complete example by combining all the steps.
#include “ns3/core-module.h”
#include “ns3/network-module.h”
#include “ns3/internet-module.h”
#include “ns3/point-to-point-module.h”
#include “ns3/lte-module.h”
#include “ns3/applications-module.h”
#include “ns3/mobility-module.h”
using namespace ns3;
NS_LOG_COMPONENT_DEFINE(“HetNetSimulation”);
void DynamicResourceAllocation(Ptr<LteHelper> lteHelper, NetDeviceContainer ueLteDevs, NetDeviceContainer macroEnbLteDevs, NetDeviceContainer smallEnbLteDevs)
{
// Example: Attach UEs to the eNB with the strongest signal or least load
for (uint32_t i = 0; i < ueLteDevs.GetN(); ++i)
{
Ptr<LteUeNetDevice> ueDevice = ueLteDevs.Get(i)->GetObject<LteUeNetDevice>();
Ptr<Node> ueNode = ueDevice->GetNode();
Ptr<MobilityModel> ueMobility = ueNode->GetObject<MobilityModel>();
double maxSignalStrength = -std::numeric_limits<double>::infinity();
Ptr<NetDevice> bestEnbDevice = nullptr;
for (uint32_t j = 0; j < macroEnbLteDevs.GetN(); ++j)
{
Ptr<LteEnbNetDevice> enbDevice = macroEnbLteDevs.Get(j)->GetObject<LteEnbNetDevice>();
Ptr<Node> enbNode = enbDevice->GetNode();
Ptr<MobilityModel> enbMobility = enbNode->GetObject<MobilityModel>();
double distance = ueMobility->GetDistanceFrom(enbMobility);
double signalStrength = -distance; // Simplified signal strength based on distance
if (signalStrength > maxSignalStrength)
{
maxSignalStrength = signalStrength;
bestEnbDevice = enbDevice;
}
}
for (uint32_t j = 0; j < smallEnbLteDevs.GetN(); ++j)
{
Ptr<LteEnbNetDevice> enbDevice = smallEnbLteDevs.Get(j)->GetObject<LteEnbNetDevice>();
Ptr<Node> enbNode = enbDevice->GetNode();
Ptr<MobilityModel> enbMobility = enbNode->GetObject<MobilityModel>();
double distance = ueMobility->GetDistanceFrom(enbMobility);
double signalStrength = -distance; // Simplified signal strength based on distance
if (signalStrength > maxSignalStrength)
{
maxSignalStrength = signalStrength;
bestEnbDevice = enbDevice;
}
}
if (bestEnbDevice)
{
lteHelper->Attach(ueDevice, bestEnbDevice);
}
}
}
int main(int argc, char *argv[])
{
CommandLine cmd;
cmd.Parse(argc, argv);
// Create nodes
NodeContainer ueNodes;
ueNodes.Create(10); // User equipment (UE) nodes
NodeContainer macroEnbNodes;
macroEnbNodes.Create(1); // Macro cell eNB (base station) node
NodeContainer smallEnbNodes;
smallEnbNodes.Create(3); // Small cell eNB (base station) nodes
// Set up LTE
Ptr<LteHelper> lteHelper = CreateObject<LteHelper>();
Ptr<PointToPointEpcHelper> epcHelper = CreateObject<PointToPointEpcHelper>();
lteHelper->SetEpcHelper(epcHelper);
Ptr<Node> pgw = epcHelper->GetPgwNode();
InternetStackHelper internet;
internet.Install(ueNodes);
// Set up mobility
MobilityHelper mobility;
mobility.SetPositionAllocator(“ns3::GridPositionAllocator”,
“MinX”, DoubleValue(0.0),
“MinY”, DoubleValue(0.0),
“DeltaX”, DoubleValue(50.0),
“DeltaY”, DoubleValue(50.0),
“GridWidth”, UintegerValue(3),
“LayoutType”, StringValue(“RowFirst”));
mobility.SetMobilityModel(“ns3::ConstantPositionMobilityModel”);
mobility.Install(macroEnbNodes);
mobility.SetMobilityModel(“ns3::ConstantPositionMobilityModel”);
mobility.Install(smallEnbNodes);
mobility.SetMobilityModel(“ns3::RandomWalk2dMobilityModel”,
“Bounds”, RectangleValue(Rectangle(-150, 150, -150, 150)));
mobility.Install(ueNodes);
// Install LTE devices to the nodes
NetDeviceContainer macroEnbLteDevs = lteHelper->InstallEnbDevice(macroEnbNodes);
NetDeviceContainer smallEnbLteDevs = lteHelper->InstallEnbDevice(smallEnbNodes);
NetDeviceContainer ueLteDevs = lteHelper->InstallUeDevice(ueNodes);
// Attach UEs to the macro eNB initially
for (uint32_t i = 0; i < ueNodes.GetN(); ++i)
{
lteHelper->Attach(ueLteDevs.Get(i), macroEnbLteDevs.Get(0));
}
// Assign IP addresses
Ipv4InterfaceContainer ueIpIface;
ueIpIface = epcHelper->AssignUeIpv4Address(NetDeviceContainer(ueLteDevs));
// Install and start applications on UEs and remote host
uint16_t dlPort = 1234;
ApplicationContainer clientApps, serverApps;
for (uint32_t i = 0; i < ueNodes.GetN(); ++i)
{
UdpClientHelper dlClient(ueIpIface.GetAddress(i), dlPort);
dlClient.SetAttribute(“Interval”, TimeValue(MilliSeconds(100)));
dlClient.SetAttribute(“MaxPackets”, UintegerValue(1000));
clientApps.Add(dlClient.Install(pgw));
UdpServerHelper dlServer(dlPort);
serverApps.Add(dlServer.Install(ueNodes.Get(i)));
}
serverApps.Start(Seconds(0.01));
clientApps.Start(Seconds(0.01));
// Schedule dynamic resource allocation
Simulator::Schedule(Seconds(1.0), &DynamicResourceAllocation, lteHelper, ueLteDevs, macroEnbLteDevs, smallEnbLteDevs);
// Enable tracing
lteHelper->EnableTraces();
Simulator::Run();
Simulator::Destroy();
return 0;
}
Overall, we had a analysis on the implementation of allocation in Heterogeneous Networks using ns3 by simulating different types of base stations that coexist, and resources are dynamically allocated to users based on various algorithms.
Get Implementation of Allocation in HetNets in ns3tool where we simulate different types of base stations based on your projects from our experts.