How to Begin Implement Network Failover in NS3

To Implement network failover in ns-3 has includes for replicate the ability of network to identify and recover from failures like as connection or node outages. This is typically established by using the terminated paths, dynamic routing protocols, or failover devices. Here’s a step-by-step guide to get started:

Steps to Begin Implement Network Failover in NS3

1. Understand Network Failover Requirements

• Describe the kind of failover we need to execution:
  • Link Failover: Manage the connection disconnections.
  • Node Failover: Maintain the node failures for sample router or switch going down.
  • Path Failover: Assure the congestion rerouting through different paths.
• Select a routing protocol which helps for dynamic failover for instance OSPF, AODV, DSDV, or a custom protocol.

2. Set Up ns-3 Environment

• Install ns-3: Enable the ns-3 is installed and functional.

git clone https://gitlab.com/nsnam/ns-3-dev.git

cd ns-3-dev

./ns3 configure –enable-examples –enable-tests

./ns3 build

• Verify the installation:

./ns3 run hello-simulator

3. Design the Network Topology

• Create a topology with redundant paths to enable failover:
  • For wired networks: It used the wired networks such as PointToPointHelper.
  • For wireless networks: It used the wireless networks like as WifiHelper or AdhocWifiMac.
• Example: A triangle of network topology by three nodes in which congestion can flow through two different paths.

4. Choose or Implement a Routing Protocol

• Use built-in dynamic routing protocols:
  • AODV (Ad-hoc On-Demand Distance Vector): Aimed at ad hoc networks.
  • OLSR (Optimized Link State Routing): Intended for proactive routing.
  • DSDV (Destination-Sequenced Distance Vector): Designed for loop-free routing.
• Ensure the routing protocol on nodes:

AodvHelper aodv;

InternetStackHelper stack;

stack.SetRoutingHelper(aodv); // Install AODV routing

stack.Install(nodes);

5. Simulate Failures

• Establish a failure through inactive a connection or during the replicate a node.
  • Example: Inactivate a point-to-point connection:

Ptr<Node> node1 = nodes.Get(0);

Ptr<Node> node2 = nodes.Get(1);

Ptr<PointToPointNetDevice> dev1 = DynamicCast<PointToPointNetDevice>(node1->GetDevice(0));

dev1->SetLinkDown();

• • Example: Replicate the node failure:

Ptr<Node> failingNode = nodes.Get(1);

failingNode->GetObject<Ipv4>()->SetDown();

6. Measure Failover Performance

• Use FlowMonitor for detect the rerouting:

FlowMonitorHelper flowmon;

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

• Log parameter metrics previously like as delay, packet delivery ratio, and throughput and after the failure.

7. Log and Visualize Results

• Use AsciiTraceHelper or custom register to record the replication of actions.
• Examine the effect of failure and recovery using tools like NetAnim or matplotlib.

8. Example Code for Network Failover

Here’s an sample where a failover occurs after a connection fails in a basic wired network:

#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”

using namespace ns3;

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

CommandLine cmd;

cmd.Parse(argc, argv);

NodeContainer nodes;

nodes.Create(3);

PointToPointHelper p2p;

p2p.SetDeviceAttribute(“DataRate”, StringValue(“10Mbps”));

p2p.SetChannelAttribute(“Delay”, StringValue(“2ms”));

NetDeviceContainer d1 = p2p.Install(nodes.Get(0), nodes.Get(1));

NetDeviceContainer d2 = p2p.Install(nodes.Get(1), nodes.Get(2));

NetDeviceContainer d3 = p2p.Install(nodes.Get(0), nodes.Get(2));

InternetStackHelper stack;

stack.Install(nodes);

Ipv4AddressHelper address;

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

Ipv4InterfaceContainer if1 = address.Assign(d1);

address.SetBase(“10.1.2.0”, “255.255.255.0”);

Ipv4InterfaceContainer if2 = address.Assign(d2);

address.SetBase(“10.1.3.0”, “255.255.255.0”);

Ipv4InterfaceContainer if3 = address.Assign(d3);

UdpEchoServerHelper echoServer(9);

ApplicationContainer serverApp = echoServer.Install(nodes.Get(2));

serverApp.Start(Seconds(1.0));

serverApp.Stop(Seconds(10.0));

UdpEchoClientHelper echoClient(if2.GetAddress(1), 9);

echoClient.SetAttribute(“MaxPackets”, UintegerValue(1));

echoClient.SetAttribute(“Interval”, TimeValue(Seconds(1.0)));

echoClient.SetAttribute(“PacketSize”, UintegerValue(1024));

ApplicationContainer clientApp = echoClient.Install(nodes.Get(0));

clientApp.Start(Seconds(2.0));

clientApp.Stop(Seconds(10.0));

// Schedule link failure

Simulator::Schedule(Seconds(4.0), &NetDevice::SetLinkDown, d1.Get(0)->GetObject<NetDevice>());

Simulator::Schedule(Seconds(6.0), &NetDevice::SetLinkUp, d1.Get(0)->GetObject<NetDevice>());

Simulator::Stop(Seconds(10.0));

FlowMonitorHelper flowmon;

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

Simulator::Run();

monitor->SerializeToXmlFile(“network-failover-results.xml”, true, true);

Simulator::Destroy();

return 0;

}

9. Test and Debug

• It executes for the replication and denotes the failover behavior.
• Alter the routing protocol for setting to enhance the failover recovery.

Here, we recognize how to calculate the Network failover by using the performance metrics like packet loss, latency, and time to recovery then it evaluate how much it takes recover from failure using the ns3 tool. We also make available advance information about how the network failover performs in other simulation tools.