How to Implement Network Power Adjustment in NS2

To implement Network Power Adjustment in NS2 has needs to include to enthusiastically adapting the transmission power of nodes to enhance energy consumption, connectivity, or network performance. This is especially useful in wireless networks like Mobile Ad-hoc Networks (MANETs), Wireless Sensor Networks (WSNs), or Vehicular Ad-hoc Networks (VANETs). The below is the brief procedure to implementing Network Power Adjustment in NS2:

Step-by-Step Implementation:

  1. Understanding Power Control in NS2
  • Power control refers to changing the transmission power of nodes to enhance communication, energy usage, and reduce interference.
  • Lowering power can conserve energy however it can diminish interaction range, foremost to potential disconnections or weaker signals.
  • In NS2, node transmission power can be controlled across the wireless physical layer parameters.
  1. Setting up NS2 Environment
  • Make sure we have NS2 installed and configured properly. You can download it from here.
  • Validate that installation has the wireless models and libraries for replicating wireless communication.
  1. Modifying Transmission Power in NS2
  • The transmission power of a node can be adapted by adjusting the power level in the physical layer. In NS2, this is configured through the Phy/WirelessPhy module.
  1. TCL Script for Power Adjustment

Below is an instance TCL script that demonstrates network power adjustment in NS2:

# Create a simulator instance

set ns [new Simulator]

# Create trace and nam files for output

set tracefile [open power_adjust.tr w]

set namfile [open power_adjust.nam w]

$ns trace-all $tracefile

$ns namtrace-all $namfile

# Define the network topology

set topo [new Topography]

$topo load_flatgrid 1000 1000  ;# Simulation area: 1000×1000 meters

# Create the General Operations Director (GOD)

set god_ [create-god 50]  ;# 50 nodes in the network

# Define node configuration parameters

set opt(chan)       Channel/WirelessChannel

set opt(prop)       Propagation/TwoRayGround

set opt(netif)      Phy/WirelessPhy

set opt(mac)        Mac/802_11

set opt(ifq)        Queue/DropTail/PriQueue

set opt(ll)         LL

set opt(ant)        Antenna/OmniAntenna

set opt(x)          1000

set opt(y)          1000

# Set default transmission power

set default_tx_power 0.2818  ;# Default transmission power (W)

# Set number of nodes

set opt(nn) 50

# Function to dynamically adjust transmission power

proc adjust_power {node tx_power} {

$node set transmitPower_ $tx_power

}

# Create nodes

for {set i 0} {$i < $opt(nn)} {incr i} {

set node_($i) [$ns node]

$node_($i) random-motion 1  ;# Enable node mobility

# Set the default transmission power for each node

$ns at 0.0 “adjust_power $node_($i) $default_tx_power”

}

# Adjust transmission power dynamically based on conditions

proc dynamic_power_adjustment {} {

global ns node_ opt

# Example: Reduce power for nodes in the range [10, 20] at time 5.0

for {set i 10} {$i <= 20} {incr i} {

$ns at 5.0 “adjust_power $node_($i) 0.1”  ;# Reduce power to 0.1W

}

# Example: Increase power for nodes in the range [30, 40] at time 10.0

for {set i 30} {$i <= 40} {incr i} {

$ns at 10.0 “adjust_power $node_($i) 0.5”  ;# Increase power to 0.5W

}

}

# Call the dynamic power adjustment function

$ns at 1.0 “dynamic_power_adjustment”

# Mobility model for nodes

for {set i 0} {$i < $opt(nn)} {incr i} {

$ns at 0.0 “$node_($i) setdest [expr rand()*1000] [expr rand()*1000] [expr rand()*10]”

}

# Traffic generation

for {set i 0} {$i < $opt(nn)} {incr i} {

# Create UDP agents and attach them to nodes

set udp_($i) [new Agent/UDP]

set null_($i) [new Agent/Null]

$ns attach-agent $node_($i) $udp_($i)

$ns attach-agent $node_($i) $null_($i)

# Generate CBR traffic

set cbr_($i) [new Application/Traffic/CBR]

$cbr_($i) set packetSize_ 512

$cbr_($i) set interval_ 0.1

$cbr_($i) attach-agent $udp_($i)

}

# Run the simulation

$ns at 1.0 “start_traffic”

$ns at 100.0 “finish”

# Traffic generation procedure

proc start_traffic {} {

global ns cbr_ opt

for {set i 0} {$i < $opt(nn)} {incr i} {

$ns at [expr 1.0 + $i*0.01] “$cbr_($i) start”

}

}

# End the simulation

proc finish {} {

global ns tracefile namfile

close $tracefile

close $namfile

$ns halt

}

$ns run

  1. Explanation of the Script
  • Node Creation: Generates 50 nodes, each with an initial transmission power of 0.2818 W.
  • Power Adjustment Procedure (adjust_power): This procedure sets the transmission power for a node at any given time.
  • Dynamic Power Adjustment: At time 5.0, the transmission power of nodes in the range [10, 20] is reduced to 0.1 W. At time 10.0, the transmission power of nodes in the range [30, 40] is increased to 0.5 W.
  • Traffic Generation: Each node creates UDP traffic using a CBR (Constant Bit Rate) traffic generator.
  1. Customizing Power Adjustment
  • Adjust Power Based on Node Distance: we can adapt the adjust_power function to modify the transmission power according to the distance among nodes. For instance, nodes closer to the destination can use lower power.
  • Energy Efficient Power Control: In a wireless sensor network, power control can be based on the left over energy of the nodes. Nodes with less remaining energy can sends at lower power to save energy.
  1. Running the Simulation
  • Save the script as power_adjust.tcl.
  • execute the script using the following command:

ns power_adjust.tcl

  • This will create a trace file (power_adjust.tr) and a NAM file (power_adjust.nam). Use the NAM file to envision node movements and the impacts of power adjustment.
  1. Analysing Results
  • Trace File Analysis: we can evaluate the trace file (power_adjust.tr) to study how power adjustment impacts the performance of the network.
    • Look for parameters like packet delivery ratio, latency, and energy consumption.
  • NAM Visualization: Use NAM to envision node movements and see how transmission power impacts connectivity and communication range.
  1. Further Enhancements
  • Adaptive Power Control: Execute adaptive algorithms that adapt the transmission power according to network conditions like link quality, congestion, or energy levels.
  • Distributed Power Control: Each node can independently decide its power level according to local information such as signal strength or node density.
  • Energy Harvesting: We can mimic energy-harvesting nodes, in which power adjustment is based on the energy being harvested in real-time.

In the above following steps briefly explain the implementation process for executing the network power adjustment in ns2 simulation tool that will help to enhance the network performance in the wireless networks. We plan to elaborate further essential details about the network power adjustment will be provided in further manual. If you’re looking for effective Network Power Adjustment results in your NS2 tool implementation, the team at ns2project.com is here to help. We can assist you in finding the best thesis ideas and topics!