How to Implement Energy Management in NS2

To implement the energy management in ns2 required to simulate a wireless networks with nodes perform with restricted energy like in wireless sensor networks (WSN) or mobile ad hoc networks (MANETs). NS2 backs the energy models which permit you to store the energy utilization of nodes during transmission, reception and idle states. It is vital when learning the performance of energy-efficient algorithms, protocols and techniques in wireless networks.

The given demonstration will help you to accomplish this management in ns2:

Key Concepts in Energy Management for NS2:

  1. Energy Model: States the energy existed to a node and the energy utilized during communication behaviors (transferring, receiving, idling, and sleeping).
  2. Energy Parameters: Configurable parameters like initial energy, transmission power, obtaining power, and idle power.
  3. Node Behavior: Nodes deplete energy depends on their activities, and eventually, they may stop performing once their energy is exhausted.

Steps to Implement Energy Management in NS2

  1. Install NS2

Make sure to install and configure the ns2 properly on your system.

  1. Set Up a Basic Energy Model for Nodes

You need to state the energy model and set up energy-related parameters for each node in your simulation. NS2 offers a built-in energy model that tracks the energy utilization of each node.

Here’s how to execute energy management in a wireless network simulation.

Example: Energy Management in a Simple Wireless Network

# Define the simulator object

set ns [new Simulator]

# Define trace and nam files for output

set tracefile [open out.tr w]

set namfile [open out.nam w]

$ns trace-all $tracefile

$ns namtrace-all $namfile

# Define a ‘finish’ procedure to end the simulation and visualize in NAM

proc finish {} {

global ns tracefile namfile

$ns flush-trace

close $tracefile

close $namfile

exec nam out.nam &

exit 0

}

# Set up the topography for the simulation area (1000m x 1000m)

set topo [new Topography]

$topo load_flatgrid 1000 1000

# Define the wireless channel

set chan [new Channel/WirelessChannel]

# Configure the energy model parameters for all nodes

set energy_model_ [new EnergyModel]

$energy_model_ set energy_ 100.0  ;# Initial energy in Joules for each node

$energy_model_ set txPower_ 0.5   ;# Energy consumption during transmission (in watts)

$energy_model_ set rxPower_ 0.3   ;# Energy consumption during reception (in watts)

$energy_model_ set idlePower_ 0.05 ;# Energy consumption during idle (in watts)

$energy_model_ set sleepPower_ 0.001 ;# Energy consumption during sleep (in watts)

# Configure the mobile node to use the energy model

$ns node-config -adhocRouting DSDV \

-llType LL \

-macType Mac/802_11 \

-ifqType Queue/DropTail/PriQueue \

-ifqLen 50 \

-antType Antenna/OmniAntenna \

-propType Propagation/TwoRayGround \

-phyType Phy/WirelessPhy \

-channel $chan \

-energyModel $energy_model_ \

-initialEnergy 100.0 \

-txPower 0.5 \

-rxPower 0.3 \

-idlePower 0.05 \

-sleepPower 0.001

# Create nodes (representing wireless sensor nodes or mobile devices)

set node1 [$ns node]

set node2 [$ns node]

set node3 [$ns node]

# Set node positions (random for now)

$node1 set X_ 200

$node1 set Y_ 200

$node1 set Z_ 0

$node2 set X_ 500

$node2 set Y_ 500

$node2 set Z_ 0

$node3 set X_ 800

$node3 set Y_ 800

$node3 set Z_ 0

# Create a duplex link between node1 and node2

$ns duplex-link $node1 $node2 2Mb 10ms DropTail

# Define TCP traffic from node1 to node3 (through node2)

set tcp [new Agent/TCP]

set sink [new Agent/TCPSink]

$ns attach-agent $node1 $tcp

$ns attach-agent $node3 $sink

$ns connect $tcp $sink

# Create FTP traffic over TCP to generate communication

set ftp [new Application/FTP]

$ftp attach-agent $tcp

$ftp start 1.0  ;# Start FTP traffic at 1 second

$ftp stop 4.5   ;# Stop FTP traffic at 4.5 seconds

# Schedule simulation end

$ns at 5.0 “finish”

# Run the simulation

$ns run

  1. Explanation of the Script
  • Energy Model: The energy model is stated and included to each node. The nodes begin with an initial energy of 100 Joules, and their energy depletes according to their actions (transmitting, receiving, idling, or sleeping).
  • Nodes and Links: Three nodes (node1, node2, and node3) are built, with a link applied amongst node1 and node2. Traffic is deliver from node1 to node3 through node2, replicating a multi-hop communication scenario.
  • Traffic: FTP traffic is created amongst the nodes over TCP to replicate data transfer.
  1. Run the Simulation

Save the script as energy_management.tcl and use the given command to execute it:

ns energy_management.tcl

This will produce a trace file (out.tr) and a NAM file (out.nam) for visualization.

  1. Visualize Energy Consumption in NAM

To visualize the simulation in NAM, use the following command:

nam out.nam

In the NAM visualization, you can monitor the packet transmission amongst the nodes. If you track energy depletion in the trace file, you can validate when nodes run out of energy and stop functioning.

  1. Monitor Energy Depletion

You can extract energy usage data by evaluating the trace file. Each node’s energy utilization is updated as they transfer or obtain packets. Process the trace file and measure the lasting energy of each node over time by using AWK, Perl, or Python scripts.

Example AWK Script to Track Remaining Energy

# Example AWK script to extract remaining energy of node1 from the trace file

awk ‘/^ENERGY/ && $3 == “node1” { print “Time: “$1, “Remaining Energy: “$4″J”}’ out.tr

This script will extract the energy-based events from the trace file and print the remaining energy of node1 at different simulation times.

  1. Simulating Different Energy Consumption Models

Simulate various characteristics by adjusting the energy usage model:

  • High-power devices: Set higher values for txPower_, rxPower_, and idlePower_.
  • Low-power devices: Set minimal values for these parameters, certainly idlePower_ and sleepPower_, to replicate energy-efficient devices.
  • Energy-hungry applications: Imitate high energy utilization by minimizing the packet size, transmission rate, or the number of traffic generated.
  1. Simulate Energy-Aware Protocols

You can also execute energy-aware routing protocols like AODV with energy metrics. NS2 helps numerous energy-efficient routing protocols in wireless networks, like:

  • Dijkstra’s algorithm with energy weights.
  • Minimum energy routing: Indicate the energy utilization by altering the link weights.
  • Energy-aware load balancing: Balance traffic among nodes to reduce energy usage.
  1. Simulate Node Failure Due to Energy Exhaustion

When a node’s energy is depleted, it will end participating in the network (no more transmission or reception). You can simulate and monitor how the network performance is impacted when nodes fail because of energy depletion.

By following the given elaborated simulation, you can acquire the knowledge about the implementation and execution of the energy management and know about how to monitor the simulation network’s energy utilization while executing. If needed, we will provide any other information which is essential for you.

If you want to implement energy management using the NS2 tool, ns2project.com is the perfect resource for you. We provide the latest ideas and topics to help you out. You can find guidance on how to improve the performance of energy-efficient algorithms, protocols, and techniques in wireless networks for your projects.