How to Start OSPF Routing projects using NS3

To start an OSPF (Open Shortest Path First) routing project utilized the NS3 tool, for follow this detailed guide:

Steps to Start OSPF Routing projects using NS3

  1. Understand OSPF
  • OSPF Overview:
    • OSPF is a link-state routing protocol utilized in a single Autonomous System (AS).
    • It used the Dijkstra’s algorithm to calculate the minimum path according to link-state advertisements (LSAs).
  • Applications:
    • Replicate the intra-AS dynamic routing.
    • We analysis the routing convergence and performance metrics such as packet delivery ratio and delay.
  1. Set Up NS3
  1. Install NS3:

sudo apt update

sudo apt install g++ python3 git cmake

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

cd ns-3-dev

./waf configure

./waf build

  1. Verify Installation:

./waf –run scratch/my-first

  1. OSPF in NS3
  • NS3 does not natively support OSPF. we can:
    1. Utilized the Quagga such as a routing suite integrated into NS3 we replicate the OSPF.
    2. Execute the custom OSPF-like protocol through encompassing their NS3’s routing classes.
    3. Estimated the OSPF behaviour utilized the static or DSDV routing.
  1. Option 1: Using Quagga to Simulate OSPF

Quagga supports OSPF and can be integrated with NS3.

Steps:

  1. Install Quagga:

sudo apt install quagga

  1. Prepare Quagga Configuration:
    • Create zebra.conf and ospfd.conf for each node in the simulation.
    • Example ospfd.conf:

router ospf

network 10.1.1.0/24 area 0

network 10.1.2.0/24 area 0

  1. QuaggaHelper Integration in NS3:
    • Use the QuaggaHelper class to integrate Quagga with NS3 nodes.

Example Code:

#include “ns3/core-module.h”

#include “ns3/network-module.h”

#include “ns3/internet-module.h”

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

#include “ns3/quagga-helper.h”

 

using namespace ns3;

int main() {

NodeContainer nodes;

nodes.Create(3); // Create 3 nodes for the network

PointToPointHelper pointToPoint;

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

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

NetDeviceContainer devices1 = pointToPoint.Install(nodes.Get(0), nodes.Get(1));

NetDeviceContainer devices2 = pointToPoint.Install(nodes.Get(1), nodes.Get(2));

InternetStackHelper stack;

stack.Install(nodes);

Ipv4AddressHelper address;

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

Ipv4InterfaceContainer interfaces1 = address.Assign(devices1);

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

Ipv4InterfaceContainer interfaces2 = address.Assign(devices2);

// Enable Quagga and OSPF

QuaggaHelper quagga;

quagga.EnableZebraDebug(nodes);

quagga.EnableOspfDebug(nodes);

quagga.EnableOspf(nodes.Get(0), “ospfd.conf.node0”);

quagga.EnableOspf(nodes.Get(1), “ospfd.conf.node1”);

quagga.EnableOspf(nodes.Get(2), “ospfd.conf.node2”);

 

Simulator::Run();

Simulator::Destroy();

return 0;

}

  1. Option 2: Approximate OSPF Using Static Routes

For small networks, you can simulate OSPF-like behavior with static routing.

Example Code:

#include “ns3/core-module.h”

#include “ns3/network-module.h”

#include “ns3/internet-module.h”

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

#include “ns3/ipv4-static-routing-helper.h”

using namespace ns3;

int main() {

NodeContainer nodes;

nodes.Create(4); // Create 4 nodes

PointToPointHelper pointToPoint;

pointToPoint.SetDeviceAttribute(“DataRate”, StringValue(“5Mbps”));

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

// Create links

NetDeviceContainer devices1 = pointToPoint.Install(nodes.Get(0), nodes.Get(1));

NetDeviceContainer devices2 = pointToPoint.Install(nodes.Get(1), nodes.Get(2));

NetDeviceContainer devices3 = pointToPoint.Install(nodes.Get(2), nodes.Get(3));

 

InternetStackHelper stack;

stack.Install(nodes);

Ipv4AddressHelper address;

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

Ipv4InterfaceContainer interfaces1 = address.Assign(devices1);

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

Ipv4InterfaceContainer interfaces2 = address.Assign(devices2);

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

Ipv4InterfaceContainer interfaces3 = address.Assign(devices3);

// Configure static routes

Ipv4StaticRoutingHelper staticRoutingHelper;

Ptr<Ipv4StaticRouting> staticRoutingNode0 = staticRoutingHelper.GetStaticRouting(nodes.Get(0)->GetObject<Ipv4>());

staticRoutingNode0->AddHostRouteTo(Ipv4Address(“10.1.3.2”), Ipv4Address(“10.1.1.2”), 1);

Ptr<Ipv4StaticRouting> staticRoutingNode1 = staticRoutingHelper.GetStaticRouting(nodes.Get(1)->GetObject<Ipv4>());

staticRoutingNode1->AddHostRouteTo(Ipv4Address(“10.1.3.2”), Ipv4Address(“10.1.2.2”), 2);

Simulator::Run();

Simulator::Destroy();

return 0;

}

  1. Option 3: Implement Custom OSPF-Like Protocol

To generate a custom OSPF-like protocol and extend the Ipv4RoutingProtocol class in NS3.

Key Features to Implement:

  1. Link-State Advertisements (LSAs):
    • The nodes are periodically interchange the link-state updates with neighbours.
  2. Dijkstra’s Algorithm:
    • We calculate the minimum paths utilized their LSAs.
  3. Routing Table Updates:
    • Dynamically update the routing tables terms on computed paths.

Skeleton Code:

#include “ns3/ipv4-routing-protocol.h”

namespace ns3 {

class OspfRoutingProtocol : public Ipv4RoutingProtocol {

public:

static TypeId GetTypeId();

OspfRoutingProtocol();

virtual ~OspfRoutingProtocol();

Ptr<Ipv4Route> RouteOutput(Ptr<Packet> packet, const Ipv4Header &header,

Ptr<NetDevice> oif, Socket::SocketErrno &sockerr) override;

void ReceiveLinkStateUpdate(uint32_t nodeId, uint32_t cost);

private:

void SendLinkStateUpdate();

void ComputeShortestPaths();

std::map<uint32_t, std::map<uint32_t, uint32_t>> linkStateDatabase; // Node -> (Neighbor -> Cost)

std::map<uint32_t, uint32_t> routingTable; // Destination -> Next Hop

};

} // namespace ns3

Throughout this report, you can completely concentrate on how to implement the OSPF (Open Shortest Path First) routing project with the help of NS3 by defining the routing protocol into the simulation. You can refer the instances and snippet codes for references.

Kick off your OSPF Routing projects with NS3! Just send all your project details to phdprojects.org, and we’ll help you achieve the best results. Share your project info with us, and we’ll guide you to success!