How to Begin Implement Network Recovery in NS3

To begin implementing and analysing the network recovery using ns3, we can replicate a network scenario in which network failure happens and execute the methods for retrieving from it like re-routing, restoring links, or redistributing traffic. Here’s a simple guide to get started:

Steps to Begin Implement Network Recovery in NS3

1. Understand the Concept

• Network Recovery consists of controlling the network failures like link/node failure and repairing typical network operations.
• General network recovery approaches like:
  • Route Reconfiguration: It used to update the routing tables for preventing failed routes.
  • Traffic Redistribution: Readdressing the traffic which helps to backup links or nodes.
  • Network Restoration: Physically or logically renovating the failed modules.

2. Set Up ns3

• We can download and install ns3 on the system properly:

./waf configure –build-profile=debug –enable-examples –enable-tests

./waf build

• Confirm the set up by executing:

./waf –run hello-simulator

3. Choose a Recovery Scenario

• Node Failure: A node flops, and traffic requires to be redirected.
• Link Failure: A link breakdowns, and another routes have to leverage.
• Congestion Recovery: High traffic is redeployed to minimize the congested routes.

4. Set Up Topology

Make a network topology that contains numerous routes among the source and destination nodes for permitting retrieval.

Example: Topology with Redundant Paths

NodeContainer nodes;

nodes.Create(6); // Node 0: Source, Node 5: Destination

// Define Point-to-Point links

PointToPointHelper p2p;

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

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

// Connect nodes

NetDeviceContainer d0 = p2p.Install(nodes.Get(0), nodes.Get(1));

NetDeviceContainer d1 = p2p.Install(nodes.Get(1), nodes.Get(2));

NetDeviceContainer d2 = p2p.Install(nodes.Get(2), nodes.Get(5));

NetDeviceContainer backup1 = p2p.Install(nodes.Get(0), nodes.Get(3));

NetDeviceContainer backup2 = p2p.Install(nodes.Get(3), nodes.Get(4));

NetDeviceContainer backup3 = p2p.Install(nodes.Get(4), nodes.Get(5));

5. Introduce Failures

During the simulation runtime, we need to replicate a failure.

Example: Link Failure

void SimulateLinkFailure(Ptr<Node> node1, Ptr<Node> node2)

{

Ptr<Ipv4> ipv4Node1 = node1->GetObject<Ipv4>();

Ptr<Ipv4> ipv4Node2 = node2->GetObject<Ipv4>();

int32_t interface1 = ipv4Node1->GetInterfaceForDevice(node1->GetDevice(0));

int32_t interface2 = ipv4Node2->GetInterfaceForDevice(node2->GetDevice(0));

ipv4Node1->SetDown(interface1);

ipv4Node2->SetDown(interface2);

NS_LOG_UNCOND(“Link between ” << node1->GetId() << ” and ” << node2->GetId() << ” failed at ” << Simulator::Now().GetSeconds() << ” seconds”);

}

Schedule the Failure

Simulator::Schedule(Seconds(5.0), &SimulateLinkFailure, nodes.Get(1), nodes.Get(2));

6. Implement Recovery Mechanism

• Re-routing: Update routing tables with the support of Ipv4GlobalRoutingHelper.

Ipv4GlobalRoutingHelper::RecomputeRoutingTables();

• Traffic Redistribution: Manually or dynamically, we can integrate the backup route.

Example: Add a Backup Route

Ptr<Ipv4> ipv4 = nodes.Get(0)->GetObject<Ipv4>();

Ipv4StaticRoutingHelper staticRoutingHelper;

Ptr<Ipv4StaticRouting> staticRouting = staticRoutingHelper.GetStaticRouting(ipv4);

// Add backup route

staticRouting->AddHostRouteTo(Ipv4Address(“10.1.3.2”), Ipv4Address(“10.1.1.1”), 1);

7. Monitor Recovery

Confirm the recovery using FlowMonitor.

Example: Set Up FlowMonitor

FlowMonitorHelper flowmonHelper;

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

Simulator::Stop(Seconds(20.0));

Simulator::Run();

monitor->SerializeToXmlFile(“recovery-flow-monitor.xml”, true, true);

8. Run the Simulation

Construct the script then execute the simulation of network recovery:

./waf –run scratch/network-recovery

9. Analyze Results

• Verify records for route updates.
• Examine FlowMonitor outcomes for metrics like throughput, delay, and packet loss before and after failure.

We have carried out effective implementation and analysis process for executing Network Recovery using a step-by-step approach in NS3 environment. More innovative insights and concepts related to this topic will be offered in the future.