• using Node class

Ptr<Node> n = CreateObject<Node>();

where CreateObject<> is a template function and Ptr<> Reference Counting Smart Pointer

• using Helper Class

NodeContainer nc;
nc.Create(3);

build a set of FdNetDevice objects attached to a physical network interface

a NetDevice to read/write network traffic from/into a file descriptor.

This class performs the actual data reading from the sockets.

build a set of FdNetDevice objects Normally we eschew multiple inheritance, however, the classes PcapUserHelperForDevice and AsciiTraceUserHelperForDevice are treated as "mixins". A mixin is a self-contained class that encapsulates a general attribute or a set of functionality that may be of interest to many other classes.

build a set of FdNetDevice objects attached to a virtual TAP network interface

build a set of FdNetDevice objects attached to a virtual TAP network interface

NS_LOG_INFO ("Create Node");
Ptr<Node> node = CreateObject<Node> ();

NS_LOG_INFO ("Create Device");
EmuFdNetDeviceHelper emu;
emu.SetDeviceName (deviceName);
NetDeviceContainer devices = emu.Install (node);
Ptr<NetDevice> device = devices.Get (0);
device->SetAttribute ("Address", localMac);

NS_LOG_INFO ("Add Internet Stack");
InternetStackHelper internetStackHelper;
internetStackHelper.SetIpv4StackInstall(true);
internetStackHelper.Install (node);

NS_LOG_INFO ("Create IPv4 Interface");
Ptr<Ipv4> ipv4 = node->GetObject<Ipv4> ();
uint32_t interface = ipv4->AddInterface (device);
Ipv4InterfaceAddress address = Ipv4InterfaceAddress (localIp, localMask);
ipv4->AddAddress (interface, address);
ipv4->SetMetric (interface, 1);
ipv4->SetUp (interface);

• Network Devices transfer packets over channels
• It incorporates Layer-1 (PHY) and Layer-2 (MAC)
• Devices interface with Layer-3 (Network)
• Layer-3 supports Layer-4 (Transport)
• Layer-4 is used by Layer-5
• Net Device are strongly bound to Channels of a matching type

• In ns-3 the basic computing device abstraction is called the node.
• The Node class provides methods for managing the representations of computing devices in simulations.

Examples: UdpEchoClientApplication, UdpEchoServerApplication

Examples: CsmaChannel(Ethernet-like), PointToPointChannel, WifiChannel

• A real Ethernet uses CSMA/CD (Carrier Sense Multiple Access with Collision Detection) scheme with exponentially increasing backoff to contend for the shared transmission medium. The ns-3 CSMA device and channel models only a subset of this.

Examples: CsmaNetDevice, PointToPointNetDevice, WifiNetDevice

• Network devices (NICs) are controlled using network device drivers collectively known as net devices.
• In Unix and Linux you refer to these net devices by names such as eth0. In ns-3 the net device abstraction covers both the software driver and the simulated hardware.
• The CsmaNetDevice is designed to work with a CsmaChannel; the PointToPointNetDevice is designed to work with a PointToPointChannel and a WifiNetNevice is designed to work with a WifiChannel.

• In a large simulated network you will need to arrange many connections between Nodes, NetDevices and Channels.
• Since connecting NetDevices to Nodes, NetDevices to Channels, assigning IP addresses, etc., are such common tasks in ns-3, we provide what we call topology helpers to make this as easy as possible.
• For example, it may take many distinct ns-3 core operations to create a NetDevice, add a MAC address, install that net device on a Node, configure the node’s protocol stack, and then connect the NetDevice to a Channel.
• Even more operations would be required to connect multiple devices onto multipoint channels and then to connect individual networks together into internetworks.
• We provide topology helper objects that combine those many distinct operations into an easy to use model for your convenience.

std::string mode = "UseBridge";
uint16_t noEnbs = 1;
Time simTime = Seconds(600);
double distance = 60.0;
string pingTarget ("10.1.1.4");
Time interPacketInterval = MilliSeconds(100);
bool disablePl=false; 

CommandLine cmd;
GlobalValue::Bind ("SimulatorImplementationType", StringValue ("ns3::RealtimeSimulatorImpl"));
cmd.AddValue("noEnbs","Number of eNodeBs", noEnbs);
cmd.AddValue ("simTime", "Total duration of the simulation", simTime);
cmd.Parse (argc,argv);

  Config::SetDefault ("ns3::LteSpectrumPhy::CtrlErrorModelEnabled", BooleanValue (false));
  Config::SetDefault ("ns3::RrFfMacScheduler::HarqEnabled", BooleanValue (false));

NodeContainer HostContainer;
HostContainer.Create(1);
Ptr<Node> Host = HostContainer.Get (0);
InternetStackHelper internet;
internet.Install (HostContainer);

PointToPointHelper p2ph;
p2ph.SetDeviceAttribute("DataRate", DataRateValue(DataRate("10Gb/s")));
p2ph.SetDeviceAttribute("Mtu",UintegerValue(1500));
p2ph.SetChannelAttribute("Delay",TimeValue(MilliSeconds(10)));
NetDeviceContainer internetDevices = p2ph.Install (Host0, Host1);
Ipv4AddressHelper ipv4h;
ipv4h.SetBase ("10.1.2.0", "255.255.255.0");
Ipv4InterfaceContainer internetIpIfaces = ipv4h.Assign(internetDevices);
Ipv4Address Host0Addr = internetIpIfaces.GetAddress(0);
Ipv4Address Host1Addr = internetIpIfaces.GetAddress(1);

Ipv4StaticRoutingHelper ipv4RoutingHelper;
Ptr<Ipv4StaticRouting> HostStaticRouting = ipv4RoutingHelper.GetStaticRouting (Host->GetObject<Ipv4>());

Ptr<V4Ping> app = CreateObject<V4Ping> ();
app->SetAttribute ("Remote", Ipv4AddressValue (externalUE));
app->SetAttribute ("Verbose", BooleanValue (true) );
remoteHost->AddApplication (app);
app->SetStartTime (Seconds (1.0));
app->SetStopTime (Seconds (120.0));