How to Implement Network Mobility Control in NS2

To implement Network Mobility Control in NS2 has needs to controlling the movement of nodes in a network. This is usually completed to enhance interaction or network performance according to particular objectives like minimizing energy usage, reducing delay, or enhancing network coverage. Stay in touch with us for novel implementation guidance we share best project ideas along with implementation support.

The below is guide on how to implement Network Mobility Control in NS2:

Step-by-Step Implementation:

  1. Understanding Mobility Control
  • Mobility control in NS2 permits to describe how nodes move in the network. It can be implemented in Mobile Ad-hoc Networks (MANETs), Vehicular Ad-hoc Networks (VANETs), or Wireless Sensor Networks (WSNs).
  • The aim of mobility control is to adapt node movement enthusiastically to enhance network performance, like maintaining connectivity, minimizing interference, or balancing load.
  1. Setting up NS2 Environment
  • Make sure that we have NS2 installed and working.
  • Ensure the NS2 environment is configured with mobility models and wireless communication libraries.
  1. Choosing a Mobility Model
  • NS2 delivers numerous built-in mobility models like Random Waypoint, Random Walk, and Gauss-Markov. These models describe on how nodes move within the network.
  • For Mobility Control, we might need to adapt or develop a custom mobility model in which the node movement is governed by external conditions such as distance to neighbors, traffic, or energy levels.
  1. Creating a Basic Network Mobility Control TCL Script

Here’s an example of how to implement basic mobility control in NS2:

# Create a simulator instance

set ns [new Simulator]

# Define the trace and nam files

set tracefile [open mobilitycontrol.tr w]

set namfile [open mobilitycontrol.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)

# 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

# Define the number of nodes and gateways

set opt(nn) 50  ;# Total number of nodes

# Create nodes

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

set node_($i) [$ns node]

$node_($i) random-motion 1  ;# Enable random motion for nodes

}

# Mobility control parameters

set max_speed 10.0  ;# Maximum speed for node movement

set min_speed 1.0   ;# Minimum speed for node movement

set pause_time 2.0  ;# Pause time between movements

# Function to control node movement dynamically based on distance to neighbors

proc control_mobility {} {

global ns node_ opt max_speed min_speed pause_time

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

set x [expr rand()*$opt(x)]

set y [expr rand()*$opt(y)]

set speed [expr $min_speed + rand()*($max_speed-$min_speed)]

$ns at 0.1 “$node_($i) setdest $x $y $speed”

}

}

# Call the mobility control procedure every few seconds

for {set time 0.0} {$time <= 100.0} {set time [expr $time + 5.0]} {

$ns at $time “control_mobility”

}

# Traffic generation

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

# Create a UDP agent for each node

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

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

# Attach traffic to nodes

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

$cbr_($i) set packetSize_ 512

$cbr_($i) set interval_ 0.1

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

}

# Start traffic at time 1.0

$ns at 1.0 “start_traffic”

$ns at 100.0 “finish”

# Traffic control 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”

}

}

# Finish the simulation

proc finish {} {

global ns tracefile namfile

close $tracefile

close $namfile

$ns halt

}

$ns run

  1. Explanation of the Script
  • Nodes Creation: The script generates 50 nodes, all capable of random motion within a 1000×1000 area.
  • Mobility Control Function (control_mobility): This procedure enthusiastically adapts the destination of each node every 5 seconds. The speed of the nodes is selected randomly among the minimum and maximum speeds defined (min_speed and max_speed).
  • Traffic Generation: Traffic is created using a UDP agent with a CBR (Constant Bit Rate) application attached to each node. The traffic is initiated at time 1.0 and continues until the simulation terminated at time 100.0.
  • Node Motion: Nodes are moved enthusiastically using the setdest command that permits to control the movement key metrics (destination coordinates and speed).
  1. Customizing Mobility Control
  • Node Mobility Based on Network Conditions: we can adapt the control_mobility procedure to modify the mobility according to network conditions, such as:
    • Distance from Neighbors: Adapt node speed or direction according to the proximity to neighboring nodes.
    • Energy Levels: Control mobility according to the energy remaining in a node (for WSNs).
    • Traffic Load: Move nodes towards areas with higher traffic to balance the load.
  1. Running the Simulation
  • Save the script as mobilitycontrol.tcl.
  • execute it using the following command:

ns mobilitycontrol.tcl

  • The script will create a trace file (mobilitycontrol.tr) and a NAM envision file (mobilitycontrol.nam). we can use NAM to envision the node movements and mobility control.
  1. Analysing Results
  • Use the trace file (mobilitycontrol.tr) to measure the performance of the mobility control:
    • Connectivity: validate if all nodes stay associated to the network as they move.
    • Packet Delivery Ratio: measure on how mobility affects the successful delivery of packets.
    • Latency: validate on how node movement impacts end-to-end delay.
  1. Further Enhancements
  • Mobility Model Customization: we can describe the custom mobility model according to real-world scenarios such as group mobility, vehicles following roads in a VANET, etc.
  • Reactive Mobility Control: execute the techniques that adapt node mobility according to real-time conditions such as signal strength, connectivity loss, or traffic congestion.
  • Energy-Efficient Mobility: For wireless sensor networks, we can enhance mobility control to minimize energy consumption by reducing node movement though maintaining connectivity.

At the end of this manual, we utterly enlightened the details and shown examples of how to execute Network Mobility Control in ns2 using the above discussed techniques. We will deliver more information according to your needs.