How to Implement Video Conferencing in ns3

To implement the video conferencing in ns3 has includes to setup the network simulation and that usually generate and observe the video traffic. This is completed by using the application and that emulates the video traffic under the UDP or TCP.

The given below is the detailed procedure on how to implement the video conferencing in ns3:

Step-by-Step Implementation:

Step 1: Setup ns3 Environment

Make certain ns3 is properly installed in the sytem.

Step 2: Include Necessary Modules

Include the necessary ns3 modules in your script:

#include “ns3/core-module.h”

#include “ns3/network-module.h”

#include “ns3/internet-module.h”

#include “ns3/point-to-point-module.h”

#include “ns3/applications-module.h”

#include “ns3/flow-monitor-module.h”

Step 3: Create the Simulation Script

1. Setup Nodes and Network:

using namespace ns3;

NS_LOG_COMPONENT_DEFINE (“VideoConferencingExample”);

class VideoStreamingApplication : public Application

{

public:

VideoStreamingApplication ();

virtual ~VideoStreamingApplication ();

void Setup (Ptr<Socket> socket, Address address, uint32_t packetSize, uint32_t nPackets, DataRate dataRate);

private:

virtual void StartApplication (void);

virtual void StopApplication (void);

void ScheduleTx (void);

void SendPacket (void);

Ptr<Socket>     m_socket;

Address         m_peer;

uint32_t        m_packetSize;

uint32_t        m_nPackets;

DataRate        m_dataRate;

EventId         m_sendEvent;

bool            m_running;

uint32_t        m_packetsSent;

};

VideoStreamingApplication::VideoStreamingApplication ()

: m_socket (0),

m_peer (),

m_packetSize (0),

m_nPackets (0),

m_dataRate (0),

m_sendEvent (),

m_running (false),

m_packetsSent (0)

{

}

VideoStreamingApplication::~VideoStreamingApplication ()

{

m_socket = 0;

}

void

VideoStreamingApplication::Setup (Ptr<Socket> socket, Address address, uint32_t packetSize, uint32_t nPackets, DataRate dataRate)

{

m_socket = socket;

m_peer = address;

m_packetSize = packetSize;

m_nPackets = nPackets;

m_dataRate = dataRate;

}

void

VideoStreamingApplication::StartApplication (void)

{

m_running = true;

m_packetsSent = 0;

m_socket->Bind ();

m_socket->Connect (m_peer);

SendPacket ();

}

void

VideoStreamingApplication::StopApplication (void)

{

m_running = false;

if (m_sendEvent.IsRunning ())

{

Simulator::Cancel (m_sendEvent);

}

if (m_socket)

{

m_socket->Close ();

}

}

 

void

VideoStreamingApplication::SendPacket (void)

{

Ptr<Packet> packet = Create<Packet> (m_packetSize);

m_socket->Send (packet);

 

if (++m_packetsSent < m_nPackets)

{

ScheduleTx ();

}

}

void

VideoStreamingApplication::ScheduleTx (void)

{

if (m_running)

{

Time tNext (Seconds (m_packetSize * 8 / static_cast<double> (m_dataRate.GetBitRate ())));

m_sendEvent = Simulator::Schedule (tNext, &VideoStreamingApplication::SendPacket, this);

}

}

int main (int argc, char *argv[])

{

CommandLine cmd;

cmd.Parse (argc, argv);

// Create nodes

NodeContainer nodes;

nodes.Create (4);

// Create point-to-point links

PointToPointHelper pointToPoint;

pointToPoint.SetDeviceAttribute (“DataRate”, StringValue (“10Mbps”));

pointToPoint.SetChannelAttribute (“Delay”, StringValue (“2ms”));

NetDeviceContainer devices;

devices = pointToPoint.Install (NodeContainer (nodes.Get (0), nodes.Get (1)));

devices.Add (pointToPoint.Install (NodeContainer (nodes.Get (1), nodes.Get (2))));

devices.Add (pointToPoint.Install (NodeContainer (nodes.Get (2), nodes.Get (3))));

// Install Internet stack

InternetStackHelper stack;

stack.Install (nodes);

// Assign IP addresses

Ipv4AddressHelper address;

address.SetBase (“10.1.1.0”, “255.255.255.0”);

Ipv4InterfaceContainer interfaces = address.Assign (devices);

// Set up applications

uint16_t port = 5000;  // Video conferencing port

// Server application on node 3

Address serverAddress (InetSocketAddress (Ipv4Address::GetAny (), port));

PacketSinkHelper packetSinkHelper (“ns3::UdpSocketFactory”, serverAddress);

ApplicationContainer sinkApps = packetSinkHelper.Install (nodes.Get (3));

sinkApps.Start (Seconds (1.0));

sinkApps.Stop (Seconds (20.0));

// Client application on node 0

Ptr<Socket> source = Socket::CreateSocket (nodes.Get (0), UdpSocketFactory::GetTypeId ());

Address remoteAddress (InetSocketAddress (interfaces.GetAddress (3), port));

Ptr<VideoStreamingApplication> app = CreateObject<VideoStreamingApplication> ();

app->Setup (source, remoteAddress, 1024, 10000, DataRate (“2Mbps”));

nodes.Get (0)->AddApplication (app);

app->SetStartTime (Seconds (2.0));

app->SetStopTime (Seconds (20.0));

// Set up a second client to simulate a conference call

Ptr<Socket> source2 = Socket::CreateSocket (nodes.Get (1), UdpSocketFactory::GetTypeId ());

Ptr<VideoStreamingApplication> app2 = CreateObject<VideoStreamingApplication> ();

app2->Setup (source2, remoteAddress, 1024, 10000, DataRate (“2Mbps”));

nodes.Get (1)->AddApplication (app2);

app2->SetStartTime (Seconds (2.0));

app2->SetStopTime (Seconds (20.0));

Simulator::Stop (Seconds (20.0));

Simulator::Run ();

Simulator::Destroy ();

return 0;

}

Step 4: Run the Simulation

Compile and run your simulation script:

sh

./waf configure

./waf build

./waf –run VideoConferencingExample

Explanation

• Node Creation: Create nodes representing different devices in the network.
• Point-to-Point Links: Configure point-to-point links between nodes with specified data rates and delays.
• Internet Stack: Install the Internet stack on all nodes.
• IP Configuration: Assign IP addresses to the interfaces.
• Applications: Implement a custom application (VideoStreamingApplication) that simulates video traffic by sending packets over UDP.
• Traffic Generation: Use the custom VideoStreamingApplication to generate video traffic from client nodes to a server node, simulating a video conferencing scenario.

Advanced Video Conferencing Techniques

1. Simulating Different Video Resolutions:

Adjust the packetSize and dataRate to simulate different video resolutions.

// Simulate HD video

app->Setup (source, remoteAddress, 1024, 10000, DataRate (“5Mbps”));

1. Quality of Service (QoS):

Implement QoS mechanisms to prioritize video traffic.

TrafficControlHelper tch;

tch.SetRootQueueDisc (“ns3::FqCoDelQueueDisc”);

tch.Install (devices);

1. Monitoring Performance:

Use the FlowMonitor module to analyze the performance of the video conferencing traffic.

FlowMonitorHelper flowmon;

Ptr<FlowMonitor> monitor = flowmon.InstallAll ();

// At the end of the simulation

monitor->SerializeToXmlFile (“video-conferencing-flowmon-results.xml”, true, true);

1. Simulating Packet Loss:

Introduce packet loss to simulate real-world network conditions.

Ptr<RateErrorModel> em = CreateObject<RateErrorModel> ();

em->SetAttribute (“ErrorRate”, DoubleValue (0.01));  // 1% packet loss

devices.Get (1)->SetReceiveErrorModel (em);

1. Simulating Multiple Streams:

Add multiple client applications to simulate a conference call with more participants.

Ptr<Socket> source3 = Socket::CreateSocket (nodes.Get (2), UdpSocketFactory::GetTypeId ());

Ptr<VideoStreamingApplication> app3 = CreateObject<VideoStreamingApplication> ();

app3->Setup (source3, remoteAddress, 1024, 10000, DataRate (“2Mbps”));

nodes.Get (2)->AddApplication (app3);

app3->SetStartTime (Seconds (2.0));

app3->SetStopTime (Seconds (20.0));

In the conclusion, we emulate the network to generate and observe the video traffic over the UDP or TCP that were executed in the ns3 tool. We plan to offer the further additional details and implementation guidance on how the video conferencing will executed in other simulation tools.