How to Implement Network Location Privacy in NS2

To implement the Network Location Privacy in NS2, we have to simulate the strategies to defend the confidentiality of user’s position in a network, usually from tracking or location intrusion attacks. The aim is to vague or anonymize the position of nodes (devices) though still upholding communication.

While NS2 does not natively assist latest privacy features, we can simulate different location privacy methods includes obfuscation, pseudonym varies, and traffic anonymization. Below is a guide to implement Network Location Privacy in NS2:

Step-by-Step Implementation:

  1. Set Up NS2

Make sure that NS2 is installed on your system. If it’s not installed, you can do so using:

sudo apt-get install ns2

  1. Define the Network Topology

Start by developing a simple network topology that has mobile nodes in which each node signifies a user or device. Then, we will imitate privacy-preserving strategies to defend the location of these nodes.

set ns [new Simulator]

set tracefile [open location_privacy.tr w]

$ns trace-all $tracefile

# Create mobile nodes that represent users/devices

set node1 [$ns node]

set node2 [$ns node]

set node3 [$ns node]

# Create links between the nodes

$ns duplex-link $node1 $node2 1Mb 10ms DropTail

$ns duplex-link $node2 $node3 1Mb 10ms DropTail

$ns duplex-link $node1 $node3 1Mb 10ms DropTail

  1. Simulate Mobile Node Movement (Dynamic Location)

Since location privacy is crucial for mobile networks, we mimic mobile nodes with altering locations. In NS2, we can simulate node mobility to denote dynamic location changes.

# Set up mobility for the nodes (node1, node2, and node3)

$node1 set X_ 50

$node1 set Y_ 50

$node1 set Z_ 0.0

$node2 set X_ 100

$node2 set Y_ 100

$node2 set Z_ 0.0

$node3 set X_ 150

$node3 set Y_ 150

$node3 set Z_ 0.0

# Change the location of the nodes over time (mobility simulation)

$ns at 5.0 “$node1 set X_ 200; $node1 set Y_ 200”

$ns at 10.0 “$node2 set X_ 250; $node2 set Y_ 250”

$ns at 15.0 “$node3 set X_ 300; $node3 set Y_ 300”

  1. Implement Location Obfuscation

Location obfuscation hides or includes noise to the actual location of nodes. This makes it harder for adversaries to define the precise location of a node.

(A) Obfuscate Location

We imitate location obfuscation by attaching random noise to the node’s actual location before transmitting location information over the network.

# Function to simulate location obfuscation by adding noise to the node’s location

proc obfuscate_location {node} {

set x [$node set X_]

set y [$node set Y_]

# Add random noise to the location (e.g., +/- 10 units of noise)

set noise_x [expr {int(rand()*20 – 10)}]

set noise_y [expr {int(rand()*20 – 10)}]

set obfuscated_x [expr $x + $noise_x]

set obfuscated_y [expr $y + $noise_y]

puts “Node location before obfuscation: X=$x, Y=$y”

puts “Node location after obfuscation: X=$obfuscated_x, Y=$obfuscated_y”

}

# Obfuscate the location of nodes during communication

$ns at 3.0 “obfuscate_location $node1”

$ns at 8.0 “obfuscate_location $node2”

$ns at 13.0 “obfuscate_location $node3”

  1. Simulate Pseudonym Changes

Pseudonym changes help guard privacy by modifying the identifiers (IDs) of nodes over time to prevent tracking. Each node occasionally alters its pseudonym to make it harder for adversaries to associate traffic with a particular user.

(A) Change Pseudonyms Over Time

We replicate pseudonym varies by updating the node IDs intermittently during the simulation.

# Function to simulate pseudonym change (node ID change)

proc change_pseudonym {node old_id new_id} {

puts “Node $old_id changes pseudonym to $new_id”

}

# Simulate pseudonym changes at different times

$ns at 4.0 “change_pseudonym node1 ‘Node1’ ‘Pseudo1′”

$ns at 9.0 “change_pseudonym node2 ‘Node2’ ‘Pseudo2′”

$ns at 14.0 “change_pseudonym node3 ‘Node3’ ‘Pseudo3′”

  1. Implement Traffic Anonymization

Traffic anonymization is intent to hide the source and destination of messages by making it harder to gather the sender or receiver. Techniques like using relay nodes or mix networks (which mix traffic from various sources) can be simulated.

(A) Simulate Anonymized Traffic Using a Relay Node

We mimic traffic anonymization by routing communication amongst two nodes through an intermediate relay node.

# Set up UDP agents for sending anonymized traffic via relay node

set udp_sender [new Agent/UDP]

set udp_relay [new Agent/UDP]

set udp_receiver [new Agent/Null]

$ns attach-agent $node1 $udp_sender

$ns attach-agent $node2 $udp_relay

$ns attach-agent $node3 $udp_receiver

# Relay communication from node1 to node3 via node2 (anonymization)

$ns connect $udp_sender $udp_relay

$ns connect $udp_relay $udp_receiver

# Create traffic generator to simulate anonymized traffic

set cbr_sender [new Application/Traffic/CBR]

$cbr_sender set packetSize_ 512

$cbr_sender set rate_ 1Mb

$cbr_sender attach-agent $udp_sender

# Start anonymized communication at 6.0 seconds

$ns at 6.0 “$cbr_sender start”

  1. Log Privacy Events

Log the privacy-preserving events like location obfuscation, pseudonym changes, and anonymized traffic to make sure that the simulation reflects privacy features.

# Function to log privacy events

proc log_event {event description} {

puts “$event: $description”

}

# Log privacy-related events during the simulation

$ns at 3.0 “log_event ‘Location Obfuscation’ ‘Node1 location was obfuscated'”

$ns at 4.0 “log_event ‘Pseudonym Change’ ‘Node1 changed its pseudonym to Pseudo1′”

$ns at 6.0 “log_event ‘Traffic Anonymization’ ‘Node1 communicates with Node3 via Node2 (Relay)'”

  1. Run the Simulation

Once the script is ready, run the simulation using NS2:

ns your_script.tcl

  1. Analyze the Results

After the simulation, validate the trace file (location_privacy.tr) and console result to verify:

  • Node positions were obfuscated successfully.
  • Nodes changed their pseudonyms over time to prevent tracking.
  • Traffic was anonymized using a convey node.

You can also use NAM (Network Animator) to envision node mobility, pseudonym changes, and traffic anonymization amongst the nodes.

  1. Extend the Simulation

You can extend this simulation by:

  • Simulating different types of adversaries: Present nodes that try to track others according to the traffic analysis or node activities.
  • Adding more privacy techniques: Execute strategies like k-anonymity or differential privacy to further guard the locations of nodes.
  • Increasing the network size: Include more nodes with changing mobility patterns to configure a more difficult and realistic scenario.
  • Simulating real-world applications: Establish scenarios like vehicular networks or IoT systems where location privacy is crucial.

The above network simulation is all about the implementation of Network Location Privacy. It can be achieved by defining the network topology and simulating Mobile Node Movement and establishing the techniques like obfuscation, pseudonym changes, and traffic anonymization. To successfully implement Network Location Privacy in NS2, we invite you to share your research details with us, as we provide excellent research ideas. If you require assistance with research, please do not hesitate to reach out to ns2project.com, as we are prepared to provide you with guidance.