How to Implement Route Source Protocol in NS2

 

To implement a Route Source Protocol in NS2 has needs to emulate a protocol that regulates the route according to the source of the packet, or more generally, routing decisions based on the source address or other features of the packet’s origin. This idea is often used in Source Routing Protocols in which the sender specifies the entire route to the destination. The given below is the implementation procedure to execute a Route Source Protocol in NS2:

Step-by-Step Implementation:

Step 1: Define the Protocol Requirements

Regulate the specific behaviour of the route source protocol that want to implement:

  • Source Routing: The sender specifies the route like Dynamic Source Routing (DSR).
  • Source-Based Decisions: The router makes decisions according to the source address like policy routing.

Step 2: Set Up NS2

Make sure NS2 is installed on system. Validate the installation by running a simple simulation and it supports numerous routing protocols that has source routing like DSR, but for custom behaviours, we might need to execute the own protocol.

Step 3: Implement the Route Source Protocol in C++

  1. Create the Route Source Protocol Agent Class

The given below are the simple structure for executing a Route Source Protocol, in which the route is regulated  based on the source address of the packet.

#include <agent.h>

#include <packet.h>

#include <trace.h>

#include <address.h>

#include <map>

class RouteSourceAgent : public Agent {

public:

RouteSourceAgent();

void recv(Packet* p, Handler* h);

void makeRoutingDecision(Packet* p);

void forwardPacket(Packet* p);

protected:

std::map<int, std::vector<int>> sourceRoutingTable_; // Source -> Path (vector of node IDs)

};

// Constructor

RouteSourceAgent::RouteSourceAgent() : Agent(PT_UDP) {

// Initialization code here

// Example: predefined routes based on source addresses

sourceRoutingTable_[1] = {2, 3, 4}; // Route for packets from source 1

sourceRoutingTable_[5] = {6, 7, 8}; // Route for packets from source 5

}

// Packet reception

void RouteSourceAgent::recv(Packet* p, Handler* h) {

// Apply source-based routing decision

makeRoutingDecision(p);

}

// Make routing decision based on the source address

void RouteSourceAgent::makeRoutingDecision(Packet* p) {

hdr_ip* iph = hdr_ip::access(p);

int src = iph->src();

if (sourceRoutingTable_.find(src) != sourceRoutingTable_.end()) {

// Use the predefined route for this source

forwardPacket(p);

} else {

// Drop or handle packets without a known source route

drop(p);

}

}

// Forward packet according to the source-based route

void RouteSourceAgent::forwardPacket(Packet* p) {

hdr_ip* iph = hdr_ip::access(p);

int src = iph->src();

int nextHop = sourceRoutingTable_[src].front();

// Remove the first hop from the path and update the packet

sourceRoutingTable_[src].erase(sourceRoutingTable_[src].begin());

// Forward the packet to the next hop

send(p, nextHop);

}

  1. Integrate the Protocol into NS2
  1. Modify the Makefile: Add new RouteSourceAgent class to the NS2 Makefile so that it acquires compiled with the rest of the simulator.
  2. Recompile NS2:

make clean

make

Step 4: Create a Tcl Script to Simulate the Route Source Protocol

Once the Route Source Protocol is executed and compiled, generate a Tcl script to emulate a network using the custom protocol.

Example Tcl Script:

# Create a simulator object

set ns [new Simulator]

# Define the topology

set val(chan)   Channel/WiredChannel

set val(ll)     LL

set val(ifq)    Queue/DropTail/PriQueue

set val(ifqlen) 50

set val(stop)   50.0

# Initialize the topology object

set topo [new Topography]

$topo load_flatgrid 500 500

# Create nodes representing routers and hosts

set router1 [$ns node]

set router2 [$ns node]

set router3 [$ns node]

set host1 [$ns node]

set host2 [$ns node]

# Establish links between routers and hosts

$ns duplex-link $router1 $router2 10Mb 10ms DropTail

$ns duplex-link $router2 $router3 10Mb 10ms DropTail

$ns duplex-link $router1 $host1 100Mb 1ms DropTail

$ns duplex-link $router3 $host2 100Mb 1ms DropTail

# Attach Route Source agents to routers

set rsagent1 [new Agent/RouteSourceAgent]

set rsagent2 [new Agent/RouteSourceAgent]

set rsagent3 [new Agent/RouteSourceAgent]

$ns attach-agent $router1 $rsagent1

$ns attach-agent $router2 $rsagent2

$ns attach-agent $router3 $rsagent3

# Set up traffic sources and sinks

set udp [new Agent/UDP]

set null [new Agent/Null]

$ns attach-agent $host1 $udp

$ns attach-agent $host2 $null

$ns connect $udp $null

# Start the simulation

$ns at 0.0 “$udp start”

$ns at $val(stop) “stop”

$ns at $val(stop) “exit 0”

proc stop {} {

global ns

$ns flush-trace

exit 0

}

# Run the simulation

$ns run

Step 5: Run the Simulation

  1. Save the Tcl script (route_source_protocol.tcl).
  2. Open a terminal and navigate to the directory in which we saved the Tcl script.
  3. Execute the simulation using the following command:

ns route_source_protocol.tcl

Step 6: Analyse the Results

  • Use trace files and the network animator (NAM) to evaluate the performance of Route Source Protocol, concentrates on the parameters such as packet delivery ratio, latency, and how well the source-based routing decisions perform.
  • Inspect on how efficiently the protocol routes packets based on their source and whether the predefined paths are used appropriately.

Additional Considerations

  • Advanced Source Routing: Execute more sophisticated source routing approaches, like permits dynamic path alterations according to the network conditions or incorporating with other routing protocols.
  • Policy-Based Routing: Expand the protocol to support complex policy-based routing decisions, like routing the particular types of traffic based on the source’s network policies.
  • Scalability: Evaluate the protocol in larger and more complex network topologies to assess its scalability and robustness.

In the above procedure, we had completely evaluated and analysed the results for compiling the simulation is to enhance the routing path by using the route source protocol features that executed in ns2 tool and also offer the more information regarding the Route Source Protocol. If you want to implement the Route Source Protocol in NS2, check out ns2project.com. Stay connected with us for the best outcomes. We also assist you in executing Source Routing Protocols, so just share your project details, and we’ll provide you with detailed guidance.