**How to Calculate Network Power Efficiency in NS2**

To calculate network power efficiency in NS2, has numerous steps to follow and it includes to measuring among the energy consumed by the network nodes and the amount of data successfully routed across the network. Power efficiency is often state as the ratio of successfully transmitted data to the total energy consumed. This is specifically relevant in wireless networks, sensor networks, and other energy-constrained networks. The below are the detailed approaches to calculate the network power efficiency in ns2:

**Steps to Calculate Network Power Efficiency in NS2:**

**Define the Simulation Setup:**In the simulation, the nodes will consume energy as they transmit, receive, or process packets. To estimate power efficiency, we required to describe an energy model that monitors the power consumption of the nodes.**Enable Energy Model in NS2:**NS2 delivers an energy model that permits to monitor the energy consumption of each node. The energy model key metrics has:**Initial Energy:**The starting energy for each node.**TxPower:**The power consumed during transmission.**RxPower:**The power consumed during reception.**IdlePower:**The power consumed while the node is idle.

Power efficiency can be defined as the ratio of successfully transmitted information to the total energy consumed by the nodes.

**Measure Energy Consumption and Data Transmission:**we can track energy consumption and the amount of data successfully routed in the course of the simulation by evaluating the trace file or using built-in NS2 energy functions.**Calculate Power Efficiency:**Power efficiency is commonly calculated using the following formula:

Power Efficiency=Total Data Successfully TransmittedTotal Energy Consumed (bits/Joule)\text{Power Efficiency} = \frac{\text{Total Data Successfully Transmitted}}{\text{Total Energy Consumed}} \ (\text{bits/Joule})Power Efficiency=Total Energy ConsumedTotal Data Successfully Transmitted (bits/Joule)

**Example Tcl Script for NS2 Simulation with Energy Model:**

Below is an sample script for replicating a network in which the nodes interact wirelessly and consume energy for the period of transmission and reception.

# Create a new simulator instance

set ns [new Simulator]

# Open a trace file to record events

set tracefile [open trace.tr w]

$ns trace-all $tracefile

# Define the energy model

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(ifqlen) 50

set val(seed) 0.0

set val(initialEnergy) 100.0 ;# initial energy of 100 Joules

set val(txPower) 0.5 ;# transmission power consumption in Watts

set val(rxPower) 0.3 ;# reception power consumption in Watts

set val(idlePower) 0.01 ;# idle power consumption in Watts

# Create the nodes

for {set i 0} {$i < 5} {incr i} {

set node($i) [$ns node]

$node($i) set X_ [expr rand()*500]

$node($i) set Y_ [expr rand()*500]

$node($i) set Z_ 0.0

# Assign the energy model to the node

$node($i) energy-model EnergyModel

$node($i) add-energy $val(initialEnergy)

$node($i) set-energy-model EnergyModel

$node($i) set-energy-monitor true

}

# Create UDP agents and traffic sources

set udp [new Agent/UDP]

set null [new Agent/Null]

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

$ns attach-agent $node(4) $null

$ns connect $udp $null

# Define a CBR traffic source

set cbr [new Application/Traffic/CBR]

$cbr attach-agent $udp

$cbr set packetSize_ 512

$cbr set rate_ 1Mb

# Schedule the traffic start and stop times

$ns at 1.0 “$cbr start”

$ns at 4.0 “$cbr stop”

$ns at 5.0 “finish”

# Define finish procedure

proc finish {} {

global ns tracefile

$ns flush-trace

close $tracefile

exit 0

}

# Run the simulation

$ns run

**Energy Consumption Measurement:**

In the simulation, each node consumes energy during transmission (txPower) and reception (rxPower). The total energy consumed by each node can be designed by measuring the node’s energy level at the end of the simulation and subtracting it from the initial energy.

NS2’s energy model monitors the energy consumption for each node. We can access the remaining energy of each node via the EnergyModel object. For sample, we can extract the remaining energy of a node at the end of the simulation like this:

# Example to print remaining energy of node(0)

puts “Node(0) remaining energy: [$node(0) energy]”

**Total Data Successfully Transmitted:**

We can estimate the total data transmitted by counting the size of the packets successfully received by the destination node. This data can be extracted from the trace file.

For instance, we can sum the number of packets received and multiply it by the packet size to estimate the total data received:

# Count the number of packets received by node 4

received_packets=$(grep “^r” trace.tr | grep “_4_” | wc -l)

# Packet size in bytes (512 bytes)

packet_size=512

# Calculate total data received in bits (1 byte = 8 bits)

total_data_transmitted=$((received_packets * packet_size * 8))

**Power Efficiency Calculation:**

The power efficiency is estimated using the following formula:

Power Efficiency (bits/Joule)=Total Data Transmitted (bits)Total Energy Consumed (Joules)\text{Power Efficiency (bits/Joule)} = \frac{\text{Total Data Transmitted (bits)}}{\text{Total Energy Consumed (Joules)}}Power Efficiency (bits/Joule)=Total Energy Consumed (Joules)Total Data Transmitted (bits)

**Example Bash Script to Calculate Power Efficiency:**

# Assume initial energy is 100 Joules for each node

initial_energy=100.0

# Calculate total energy consumed by node 0 and node 4 (example)

energy_node_0=$(grep “Node(0) remaining energy:” trace.tr | awk ‘{print $4}’)

energy_node_4=$(grep “Node(4) remaining energy:” trace.tr | awk ‘{print $4}’)

# Calculate energy consumed by nodes

energy_consumed_node_0=$(echo “$initial_energy – $energy_node_0” | bc)

energy_consumed_node_4=$(echo “$initial_energy – $energy_node_4” | bc)

# Total energy consumed

total_energy_consumed=$(echo “$energy_consumed_node_0 + $energy_consumed_node_4” | bc)

# Total data transmitted in bits

total_data_transmitted=$((received_packets * packet_size * 8))

# Calculate power efficiency

if [ $(echo “$total_energy_consumed > 0” | bc) -eq 1 ]; then

power_efficiency=$(echo “scale=4; $total_data_transmitted / $total_energy_consumed” | bc)

echo “Network Power Efficiency: $power_efficiency bits/Joule”

else

echo “No energy consumed.”

fi

**Summary of Steps:**

**Enable the energy model**in NS2 to monitor power consumption for each node.**Run the simulation**to create a trace file that logs sent, received, and energy-related events.**Measure energy consumption**by estimating the difference among the initial and remaining energy of each node.**Measure total data transmitted**by summing up the successfully received packets and converting them to bits.**Calculate power efficiency**by way of the ratio of total data transmitted (in bits) to total energy consumed (in Joules).

Finally, we had clearly offered the detailed descriptions to compute the network power efficiency was given above that were evaluated in ns2 implementation tool. We also further provide the detailed information that related to network power efficiency. Our team assists you in determining the Network Power Efficiency using the NS2 tool, tailored to your project concepts and themes that we provide. Engage with our experts to complete your tasks effectively. We specialize in wireless networks, sensor networks, and other energy-limited networks. Please share the specifics of your project with us, and we will offer our support.