How to Implement IoT in ns2

To implement an Internet of Things (IoT) network in the simulation tool ns2 (Network Simulator 2) has encompasses mimicking a network in which several IoT devices like sensors, actuators, smart devices are communicate with each other and maybe with a central server or cloud. These networks are usually including heterogeneous devices, frequently need efficient data routing and management strategies, and changing the communication protocols. For assistance in implementing IoT within the ns2 tool, please do not hesitate to reach out to us. We are prepared to provide you with the most suitable topics and ideas.

Step-by-Step Implementations:

Conceptual Overview

In an IoT network:

  1. IoT Devices: This devices might be sensors, actuators, or smart devices that gather data or execute actions based on received commands.
  2. Communication Protocols: It can use the protocols such as MQTT, CoAP, or even simple TCP/UDP for basic scenarios that normally communicate.
  3. Gateway/Server: For processing, a central node or gateway that gathers data from the IoT devices and sends it to a server or cloud.

Step 1: Conceptualize the IoT Simulation

For this emulation, we shall make a basic IoT scenario with numerous IoT devices that communicate with a central gateway or server. The devices will forward data to the gateway that can perform as a sink node.

Step 2: Create the Tcl Script

The following is an instance Tcl script that mimics a simple IoT network scenario in ns2.

Example Tcl Script for Simulating IoT in ns2

# Create a simulator object

set ns [new Simulator]

# Define the topography object (for a moderate area)

set topo [new Topography]

$topo load_flatgrid 1000 1000  # 1km x 1km area

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

create-god 6  # Number of nodes (5 IoT devices + 1 gateway/server)

# Configure the nodes for the IoT network

$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 \

-channelType Channel/WirelessChannel \

-topoInstance $topo \

-agentTrace ON \

-routerTrace ON \

-macTrace ON \

-movementTrace OFF

# Open trace and NAM files for recording the simulation

set tracefile [open iot_out.tr w]

$ns trace-all $tracefile

set namfile [open iot_out.nam w]

$ns namtrace-all-wireless $namfile 1000 1000

# 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 iot_out.nam &

exit 0

}

# Create IoT devices (sensors/actuators)

set iot1 [$ns node]

set iot2 [$ns node]

set iot3 [$ns node]

set iot4 [$ns node]

set iot5 [$ns node]

# Create a gateway/server node

set gateway [$ns node]

# Set initial positions for IoT devices and gateway

$iot1 set X_ 100.0

$iot1 set Y_ 200.0

$iot1 set Z_ 0.0

$iot2 set X_ 300.0

$iot2 set Y_ 400.0

$iot2 set Z_ 0.0

$iot3 set X_ 500.0

$iot3 set Y_ 600.0

$iot3 set Z_ 0.0

$iot4 set X_ 700.0

$iot4 set Y_ 800.0

$iot4 set Z_ 0.0

$iot5 set X_ 900.0

$iot5 set Y_ 900.0

$iot5 set Z_ 0.0

$gateway set X_ 500.0

$gateway set Y_ 500.0

$gateway set Z_ 0.0

# Define a custom procedure for simulating IoT data transmission

proc send_iot_data {src dst packetSize rate} {

global ns

# Create a UDP agent to simulate IoT data traffic

set udp [new Agent/UDP]

$ns attach-agent $src $udp

set null [new Agent/Null]

$ns attach-agent $dst $null

$ns connect $udp $null

# Generate IoT data traffic using a CBR application

set cbr [new Application/Traffic/CBR]

$cbr attach-agent $udp

$cbr set packetSize_ $packetSize

$cbr set rate_ $rate

$cbr start

}

# Simulate IoT data transmission from devices to the gateway

$ns at 2.0 “send_iot_data $iot1 $gateway 512 100Kb”

$ns at 4.0 “send_iot_data $iot2 $gateway 512 100Kb”

$ns at 6.0 “send_iot_data $iot3 $gateway 512 100Kb”

$ns at 8.0 “send_iot_data $iot4 $gateway 512 100Kb”

$ns at 10.0 “send_iot_data $iot5 $gateway 512 100Kb”

# Schedule the end of the simulation

$ns at 20.0 “finish”

# Run the simulation

$ns run

Step 3: Run the Tcl Script

Here, we can save the script with a .tcl extension, for instance, iot_simulation.tcl. Afterwards, we run the script using the below command in the terminal:

ns iot_simulation.tcl

Step 4: Visualize the Simulation

Now, we can visualize the simulation, open the created NAM file using:

nam iot_out.nam

Script Explanation

  • IoT Devices: The nodes iot1 to iot5 are signify IoT devices that make data and forward it to the gateway.
  • Gateway Node: The gateway node performs as a central point in which IoT data is gathered and possibly forwarded to a cloud server.
  • IoT Data Transmission: The send_iot_data process is mimics the IoT data transmission using the UDP, which is general in numerous IoT applications because of its simplicity and effectiveness.

Customization

  • Different Protocols: We can test with other protocols such as TCP for reliable data delivery or emulate the lightweight IoT protocols like MQTT or CoAP.
  • Varying Data Rates: To modify the data rates and packet sizes to mimic various IoT applications, like environmental monitoring, smart homes, or industrial IoT.
  • Energy Efficiency: To Integrate the energy-efficient protocols to emulate power-constrained IoT devices.
  • Mobility: We execute the mobility models if the IoT devices or gateway are mobile, like in vehicular IoT scenarios.

Limitations

  • Simplified IoT Model: The script offers a simple model of IoT communication. It does not account for the complete difficulty of real-world IoT networks, like network heterogeneity or intermittent connectivity.
  • No Physical Layer Simulation: This script does not mimic the physical layer features particular to IoT networks, like interference, signal degradation, or battery life.
  • Limited Protocol Support: The simulation tool ns2 has limited support for IoT-particular protocols like MQTT, CoAP, or 6LoWPAN that are generally used in real IoT networks.

The procedure for IoT was executed methodically, then implemented using the simulation tool ns2. We will explore this topic indepth using different simulation tools as needed providing a comprehensive analysis.