How to Start VANET Protocols Projects Using NS2

To start a Vehicular Ad Hoc Network (VANET) protocol project using NS2, it encompasses to replicate the communication and routing protocols which is created for vehicles. VANET protocols normally focus tasks like high mobility, dynamic topology, and low latency needs. NS2 environment can be prolonged for VANET simulations by means of combining mobility models and executing related protocols.

Below is a complete instruction to get started:

Steps to Start VANET Protocols Projects in NS2

  1. Understand VANET Protocols and NS2 Capabilities
  • VANET Protocols:
    • Reactive Routing: AODV (Ad-hoc On-Demand Distance Vector), DSR (Dynamic Source Routing).
    • Proactive Routing: OLSR (Optimized Link State Routing).
    • Geographic Routing: GPSR (Greedy Perimeter Stateless Routing).
  • NS2 Features:
    • It provides basic MANET protocols such as AODV, DSR, and DSDV.
    • It can be prolonged with mobility patterns and VANET-specific protocols.
  1. Set Up Your Environment
  • Install NS2:

sudo apt-get install ns2

  • Confirm installation by running an example script:

ns example.tcl

  1. Define the Project Scope
  • Objectives:
    • Replicate the VANET protocols within a realistic urban or highway situation.
    • Examine the performance parameters such as packet delivery ratio, end-to-end delay, and routing overhead.
    • Then, equate the VANET-specific protocols such as GPSR including AODV which is custom protocols.
  • Example Scenarios:
    • In high-mobility environment, we can estimate the GPSR.
    • Experiment the performance of AODV under a multi-lane highway situation.
  1. Design the Network Topology
  • Topology Elements:
    • Nodes: It denotes the vehicles.
    • Links: Signify wireless interaction connections among the vehicles.
  • Example Topology:
    • It has 50 vehicles with 1500m x 1500m grid that are arbitrarily transferring or near to predefined paths.
  1. Implement Mobility Models
  • Step 1: Use SUMO (Simulation of Urban Mobility):
    • Make a realistic vehicular movement traces with SUMO.
    • Transfer traces within NS2-compatible format.
  • Step 2: Implement NS2 Mobility Model:
    • Make use of random waypoint or predefined mobility models for simple simulations.

Example NS2 Mobility Model:

$node(0) setdest 500 500 20.0

$node(1) setdest 700 300 15.0

$node(2) setdest 300 600 10.0

  1. Write the TCL Script
  • Set the VANET routing protocols, mobility, and traffic sources using TCL script.

Example TCL Script for VANET Using AODV:

# Initialize the simulator

set ns [new Simulator]

# Define trace and NAM files

set tracefile [open vanet_trace.tr w]

$ns trace-all $tracefile

set namfile [open vanet_simulation.nam w]

$ns namtrace-all-wireless $namfile 1500 1500

# Configure wireless topology

set val(chan)           Channel/WirelessChannel

set val(prop)           Propagation/TwoRayGround

set val(netif)          Phy/WirelessPhy

set val(mac)            Mac/802_11

set val(ifq)            Queue/DropTail/PriQueue

set val(ll)             LL

set val(ant)            Antenna/OmniAntenna

set val(x)              1500

set val(y)              1500

set val(ifqlen)         50

# Create nodes

set num_nodes 50

for {set i 0} {$i < $num_nodes} {incr i} {

set node($i) [$ns node]

$node($i) random-motion 1

}

# Set routing protocol to AODV

$ns rtproto AODV

# Configure mobility

$node(0) setdest 500 500 10.0

$node(1) setdest 700 300 15.0

$node(2) setdest 300 600 20.0

# Define traffic

set tcp [new Agent/TCP]

set sink [new Agent/TCPSink]

$ns attach-agent $node(0) $tcp

$ns attach-agent $node(49) $sink

$ns connect $tcp $sink

set ftp [new Application/FTP]

$ftp attach-agent $tcp

$ns at 5.0 “$ftp start”

$ns at 15.0 “$ftp stop”

# Terminate simulation

$ns at 20.0 “finish”

proc finish {} {

global ns tracefile namfile

$ns flush-trace

close $tracefile

close $namfile

exec nam vanet_simulation.nam &

exit 0

}

$ns run

  1. Simulate Network Dynamics
  • High Mobility: Describe the realistic movement models or import SUMO traces.
  • Network Partitioning: Launch link failures for analysing the robustness of protocol.
  1. Run the Simulation
  • We can run the TCL script simulation:

ns vanet_simulation.tcl

  • Utilise NAM to envision the simulation:

nam vanet_simulation.nam

  1. Analyze Performance
  • Obtain performance parameters from the trace file as vanet_trace.tr:
    • Packet Delivery Ratio (PDR): Compute the percentage of packets that were effectively distributed.
    • Routing Overhead: Measure the volume of control packets which are swapped.
    • End-to-End Delay: Calculate the average duration for packet delivery.

Example AWK Script for PDR:

BEGIN {sent=0; received=0;}

{

if ($1 == “s” && $4 == “TCP”) {

sent++;

} else if ($1 == “r” && $4 == “TCP”) {

received++;

}

}

END {

print “Packet Delivery Ratio:”, received/sent;

}

  1. Enhance VANET Protocols
  • QoS Extensions: Integrate the QoS aspects for low-latency interaction within safety-critical scenarios.
  • Security: Execute the encryption or verification for routing messages.
  • Energy Optimization: Experiment the VANET protocols within power-constrained settings such as electric vehicles.
  1. Document the Project
  • For research and project purpose, it offers detailed insights such as:
    • Clear problem statement and project goals.
    • Create a network topology and configurations.
    • Visualize the simulation outcomes like graphs, tables.
    • Observations and references.

Suggested Enhancements

  • Comparison Studies: We can equate the routing protocols AODV, DSR, GPSR, and OLSR’s delay, scalability, and robustness.
  • Scalability Testing: Replicate the VANET within larger networks including hundreds of vehicles.
  • Realistic Traffic Patterns: Integrate the realistic traffic models such as video streaming or HTTP.

We gave a thorough step-by-step explanation of VANET Protocols Projects simulation with related sample coding in NS2 environment, with further innovative details to be included in the next manual.