How to Implement Wireless in ns2

To implement a wireless network in ns2 has needs to configure the simulation environment that emulate the wireless communication, describing node mobility, and specifying communication protocols. The given below is the procedure to implement the wireless communication in ns2.

Step-by-Step Implementation:

Step 1: Set Up the Basic Simulation Environment

We need to initiate by configuring the simulation environment that encompass to describe the network topology, node configuration, and mobility model.

Example Tcl Script

# Create a simulator object

set ns [new Simulator]

# Define the topography object

set topo [new Topography]

$topo load_flatgrid 500 500

# Create the General Operations Director (GOD) for wireless simulations

create-god 5 # Number of nodes

# Configure the node mobility model and wireless settings

$ns node-config -adhocRouting AODV \

-llType LL \

-macType Mac/802_11 \

-ifqType Queue/DropTail/PriQueue \

-ifqLen 50 \

-antType Antenna/OmniAntenna \

-propType Propagation/TwoRayGround \

-phyType Phy/WirelessPhy \

-topoInstance $topo \

-agentTrace ON \

-routerTrace ON \

-macTrace ON \

-movementTrace ON

# Open trace and NAM files for recording the simulation

set tracefile [open wireless_out.tr w]

$ns trace-all $tracefile

set namfile [open wireless_out.nam w]

$ns namtrace-all-wireless $namfile 500 500

# Define a finish procedure to close files and end the simulation

proc finish {} {

global ns tracefile namfile

$ns flush-trace

close $tracefile

close $namfile

exec nam wireless_out.nam &

exit 0

}

# Create wireless nodes

set n0 [$ns node]

set n1 [$ns node]

set n2 [$ns node]

set n3 [$ns node]

set n4 [$ns node]

# Set initial positions for the nodes

$n0 set X_ 50.0

$n0 set Y_ 50.0

$n0 set Z_ 0.0

$n1 set X_ 150.0

$n1 set Y_ 150.0

$n1 set Z_ 0.0

$n2 set X_ 250.0

$n2 set Y_ 250.0

$n2 set Z_ 0.0

$n3 set X_ 350.0

$n3 set Y_ 350.0

$n3 set Z_ 0.0

$n4 set X_ 450.0

$n4 set Y_ 450.0

$n4 set Z_ 0.0

# Define node movements (mobility)

$ns at 5.0 “$n0 setdest 300.0 300.0 10.0”

$ns at 10.0 “$n1 setdest 100.0 100.0 10.0”

$ns at 15.0 “$n2 setdest 400.0 400.0 10.0”

$ns at 20.0 “$n3 setdest 200.0 200.0 10.0”

$ns at 25.0 “$n4 setdest 50.0 50.0 10.0”

# Define traffic between nodes

# TCP Traffic from n0 to n4

set tcp0 [new Agent/TCP]

$ns attach-agent $n0 $tcp0

set sink0 [new Agent/TCPSink]

$ns attach-agent $n4 $sink0

$ns connect $tcp0 $sink0

set ftp0 [new Application/FTP]

$ftp0 attach-agent $tcp0

$ftp0 start

# UDP Traffic from n1 to n3

set udp1 [new Agent/UDP]

$ns attach-agent $n1 $udp1

set null1 [new Agent/Null]

$ns attach-agent $n3 $null1

$ns connect $udp1 $null1

set cbr1 [new Application/Traffic/CBR]

$cbr1 attach-agent $udp1

$cbr1 set packetSize_ 500

$cbr1 set rate_ 1Mb

$cbr1 start 2.0

# Schedule the end of the simulation

$ns at 30.0 “finish”

# Run the simulation

$ns run

Step 2: Running the Tcl Script

Once writing the Tcl script, save it with a .tcl extension like wireless_simulation.tcl. Open a terminal and run the following command:

ns wireless_simulation.tcl

This command will execute the simulation and make a trace file (wireless_out.tr) and a NAM file (wireless_out.nam).

Step 3: Visualize the Wireless Network

To visualize the wireless network, open the NAM file with the following command:

nam wireless_out.nam

This will present the NAM tool that permits to see the wireless nodes’ movement and communication.

Script Explanation

Simulator Object: $ns [new Simulator] make the simulator instance.
Topography: The topography object ($topo) outlines the simulation area size where is set to 500×500.
Node Configuration: $ns node-config sets the wireless node parameters that have the routing protocol (AODV), MAC type (802.11), and antenna type (OmniAntenna).
Node Placement: Nodes are placed at particular (X, Y, Z) coordinates using the set X_, set Y_, and set Z_ commands.
Node Mobility: Node movements are described using the setdest command where the particular destination coordinates and speed.
Traffic Definition: TCP and UDP traffic flows are described among numerous nodes. FTP is used over TCP, and CBR (Constant Bit Rate) traffic is used in UDP.
Finish Procedure: at the end of the simulation it cleans up and closes files in the terminated process.

Customization

Change Mobility Model: Execute the various mobility models by varying the setdest commands.
Modify Node Configuration: Adapts the node properties such as transmission range, antenna type, or routing protocol.
Add More Nodes: Maximize the number of nodes and state the additional traffic patterns.
Experiment with Different Protocols: Try various routing protocols such as DSR or DSDV to see their effects on performance.

From this manual, we had successfully delivered the significant information regarding the execution procedures for wireless with the help of ns2 simulator and also we provide more information about how the wireless network will perform in other simulation tool.

We have curated a range of ideas and topics related to wireless in NS2 readily available for scholars. If you’re seeking additional project guidance and implementation support, look no further than ns2projects.com.