To implement the topology based routing in ns3 has encompasses to generate a routing protocol that uses the network topology data to make the routing decisions. We specialize in providing detailed comparisons regarding Topology based Routing in ns3 simulation. Our expertise lies in utilizing network topology data to make informed routing decisions. Reach out to ns3simulation.com for further guidance.
Below is the detailed procedure on how to implement the topology-based routing protocol in ns3:
Step-by-Step Procedure:
Step 1: Set Up the ns3 Environment
- Install ns3: Make sure ns3 is installed in the computer.
sudo apt-get update
sudo apt-get install ns3
Create a New ns3 Project: Create a directory for your new project within the ns3 workspace.
cd ns-3
mkdir scratch/topology-based-routing
Step 2: Define the Topology-Based Routing Protocol
- Create the Routing Protocol Class: Define a new routing protocol class that implements your topology-based routing algorithm.
// TopologyBasedRoutingProtocol.h
#ifndef TOPOLOGY_BASED_ROUTING_PROTOCOL_H
#define TOPOLOGY_BASED_ROUTING_PROTOCOL_H
#include “ns3/ipv4-routing-protocol.h”
#include “ns3/ipv4.h”
#include “ns3/ipv4-routing-table-entry.h”
#include “ns3/timer.h”
#include <map>
#include <vector>
namespace ns3 {
class TopologyBasedRoutingProtocol : public Ipv4RoutingProtocol {
public:
static TypeId GetTypeId (void);
TopologyBasedRoutingProtocol ();
virtual ~TopologyBasedRoutingProtocol ();
virtual Ptr<Ipv4Route> RouteOutput (Ptr<Packet> p, const Ipv4Header &header, Ptr<NetDevice> oif, Socket::SocketErrno &sockerr);
virtual bool RouteInput (Ptr<const Packet> p, const Ipv4Header &header, Ptr<const NetDevice> idev, UnicastForwardCallback ucb, MulticastForwardCallback mcb, LocalDeliverCallback lcb, ErrorCallback ecb);
virtual void NotifyInterfaceUp (uint32_t interface);
virtual void NotifyInterfaceDown (uint32_t interface);
virtual void NotifyAddAddress (uint32_t interface, Ipv4InterfaceAddress address);
virtual void NotifyRemoveAddress (uint32_t interface, Ipv4InterfaceAddress address);
virtual void SetIpv4 (Ptr<Ipv4> ipv4);
virtual void PrintRoutingTable (Ptr<OutputStreamWrapper> stream, Time::Unit unit = Time::S) const;
private:
void DiscoverTopology ();
void UpdateRoutingTable ();
Ptr<Ipv4> m_ipv4;
std::map<Ipv4Address, Ipv4RoutingTableEntry> m_routes;
Timer m_topologyDiscoveryTimer;
};
} // namespace ns3
#endif // TOPOLOGY_BASED_ROUTING_PROTOCOL_H
// TopologyBasedRoutingProtocol.cc
#include “TopologyBasedRoutingProtocol.h”
#include “ns3/log.h”
#include “ns3/ipv4-l3-protocol.h”
namespace ns3 {
NS_LOG_COMPONENT_DEFINE (“TopologyBasedRoutingProtocol”);
NS_OBJECT_ENSURE_REGISTERED (TopologyBasedRoutingProtocol);
TypeId TopologyBasedRoutingProtocol::GetTypeId (void) {
static TypeId tid = TypeId (“ns3::TopologyBasedRoutingProtocol”)
.SetParent<Ipv4RoutingProtocol> ()
.SetGroupName (“Internet”)
.AddConstructor<TopologyBasedRoutingProtocol> ();
return tid;
}
TopologyBasedRoutingProtocol::TopologyBasedRoutingProtocol () {
m_topologyDiscoveryTimer.SetFunction (&TopologyBasedRoutingProtocol::DiscoverTopology, this);
m_topologyDiscoveryTimer.Schedule (Seconds (5.0)); // Example periodic interval for topology discovery
}
TopologyBasedRoutingProtocol::~TopologyBasedRoutingProtocol () {}
void TopologyBasedRoutingProtocol::SetIpv4 (Ptr<Ipv4> ipv4) {
m_ipv4 = ipv4;
}
void TopologyBasedRoutingProtocol::NotifyInterfaceUp (uint32_t interface) {}
void TopologyBasedRoutingProtocol::NotifyInterfaceDown (uint32_t interface) {}
void TopologyBasedRoutingProtocol::NotifyAddAddress (uint32_t interface, Ipv4InterfaceAddress address) {}
void TopologyBasedRoutingProtocol::NotifyRemoveAddress (uint32_t interface, Ipv4InterfaceAddress address) {}
Ptr<Ipv4Route> TopologyBasedRoutingProtocol::RouteOutput (Ptr<Packet> p, const Ipv4Header &header, Ptr<NetDevice> oif, Socket::SocketErrno &sockerr) {
Ipv4Address dst = header.GetDestination ();
// Check if a route exists in the routing table
if (m_routes.find (dst) != m_routes.end ()) {
Ipv4RoutingTableEntry route = m_routes[dst];
Ptr<Ipv4Route> ipv4Route = Create<Ipv4Route> ();
ipv4Route->SetDestination (route.GetDest ());
ipv4Route->SetGateway (route.GetGateway ());
ipv4Route->SetOutputDevice (m_ipv4->GetNetDevice (route.GetInterface ()));
ipv4Route->SetSource (route.GetSource ());
return ipv4Route;
}
sockerr = Socket::ERROR_NOROUTETOHOST;
return 0;
}
bool TopologyBasedRoutingProtocol::RouteInput (Ptr<const Packet> p, const Ipv4Header &header, Ptr<const NetDevice> idev, UnicastForwardCallback ucb, MulticastForwardCallback mcb, LocalDeliverCallback lcb, ErrorCallback ecb) {
Ipv4Address dst = header.GetDestination ();
// Check if the packet is for this node
for (uint32_t i = 0; i < m_ipv4->GetNInterfaces (); i++) {
for (uint32_t j = 0; j < m_ipv4->GetNAddresses (i); j++) {
if (m_ipv4->GetAddress (i, j).GetLocal () == dst) {
lcb (p, header, i);
return true;
}
}
}
// Check if a route exists in the routing table
if (m_routes.find (dst) != m_routes.end ()) {
Ipv4RoutingTableEntry route = m_routes[dst];
ucb (route, p, header);
return true;
}
return false;
}
void TopologyBasedRoutingProtocol::PrintRoutingTable (Ptr<OutputStreamWrapper> stream, Time::Unit unit) const {
*stream->GetStream () << “Topology-Based Routing Table:\n”;
for (auto &route : m_routes) {
route.second.Print (stream);
}
}
void TopologyBasedRoutingProtocol::DiscoverTopology () {
// Implement topology discovery logic here
// Example: Send topology discovery packets and update routing table
UpdateRoutingTable ();
m_topologyDiscoveryTimer.Schedule (Seconds (5.0)); // Reschedule the timer for periodic discovery
}
void TopologyBasedRoutingProtocol::UpdateRoutingTable () {
// Implement routing table update logic based on discovered topology
}
} // namespace ns3
Step 3: Integrate the Routing Protocol in a Simulation
- Create a New Simulation Script: Create a new script in your scratch directory to use the topology-based routing protocol.
// topology-based-routing.cc
#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 “TopologyBasedRoutingProtocol.h”
using namespace ns3;
NS_LOG_COMPONENT_DEFINE (“TopologyBasedRoutingExample”);
int main (int argc, char *argv[]) {
CommandLine cmd;
cmd.Parse (argc, argv);
NodeContainer nodes;
nodes.Create (6);
PointToPointHelper pointToPoint;
pointToPoint.SetDeviceAttribute (“DataRate”, StringValue (“5Mbps”));
pointToPoint.SetChannelAttribute (“Delay”, StringValue (“2ms”));
NetDeviceContainer devices;
for (uint32_t i = 0; i < nodes.GetN (); ++i) {
for (uint32_t j = i + 1; j < nodes.GetN (); ++j) {
NodeContainer pair (nodes.Get (i), nodes.Get (j));
devices.Add (pointToPoint.Install (pair));
}
}
InternetStackHelper stack;
Ptr<TopologyBasedRoutingProtocol>topologyRouting=CreateObject<TopologyBasedRoutingProtocol> ();
stack.SetRoutingHelper (topologyRouting);
stack.Install (nodes);
Ipv4AddressHelper address;
address.SetBase (“10.1.1.0”, “255.255.255.0”);
Ipv4InterfaceContainer interfaces = address.Assign (devices);
UdpEchoServerHelper echoServer (9);
ApplicationContainer serverApps = echoServer.Install (nodes.Get (0));
serverApps.Start (Seconds (1.0));
serverApps.Stop (Seconds (10.0));
UdpEchoClientHelper echoClient (interfaces.GetAddress (0), 9);
echoClient.SetAttribute (“MaxPackets”, UintegerValue (1));
echoClient.SetAttribute (“Interval”, TimeValue (Seconds (1.0)));
echoClient.SetAttribute (“PacketSize”, UintegerValue (1024));
ApplicationContainer clientApps;
for (uint32_t i = 1; i < nodes.GetN (); ++i) {
clientApps.Add (echoClient.Install (nodes.Get (i)));
}
clientApps.Start (Seconds (2.0));
clientApps.Stop (Seconds (10.0));
Simulator::Run ();
Simulator::Destroy ();
return 0;
}
Step 4: Compile and Run the Simulation
- Compile the Script: Compile your script using the waf build system.
./waf build
Run the Simulation: Run your simulation script and observe the results.
./waf –run scratch/topology-based-routing
Step 5: Enable Tracing and Analyze Results
- Enable Tracing: Add tracing to collect data for analysis.
AsciiTraceHelper ascii;
pointToPoint.EnableAsciiAll (ascii.CreateFileStream (“topology-based-routing.tr”));
Run the Simulation: Set the simulation stop time and run it.
Simulator::Stop (Seconds (10.0));
Simulator::Run ();
Simulator::Destroy ();
Step 6: Analyze the Results
After running the simulation, analyse the generated trace files (topology-based-routing.tr) to study the routing behaviour and performance.
In the conclusion, we had successfully implemented the topology based routing in ns3 by creating the network topology to generate the appropriate decision. We also provide further information that relates to topology based routing.