How to Implement Network CoC Preservation in NS2

To implement the Network Chain of Custody (CoC) Preservation in NS2, we have to make certain that the data is transferred through the network while upholding its integrity, validity and traceability throughout its journey amongst nodes. In these scenarios, we can concentrate on tracking and logging the managing of packets, certifying their integrity at every hop and making sure that illegal alterations or accesses are identified and repaired.

Below is a step-by-step guide to implementing Network Chain of Custody Preservation in NS2:

Step-by-Step Implementation:

  1. Set Up NS2

Make sure that NS2 is installed on your system. If not, you can install it using the below command:

sudo apt-get install ns2

  1. Define the Network Topology

Begin by setting up the network topology in ns2 with nodes can interchange data. We will also imitate a process to store and check the CoC for the transferred data.

Example:

set ns [new Simulator]

set tracefile [open coc_preservation.tr w]

$ns trace-all $tracefile

# Create nodes

set n1 [$ns node]  ;# Sender node

set n2 [$ns node]  ;# Receiver node

set n3 [$ns node]  ;# Intermediate node 1

set n4 [$ns node]  ;# Intermediate node 2

# Create links between the nodes

$ns duplex-link $n1 $n3 1Mb 10ms DropTail

$ns duplex-link $n3 $n4 1Mb 10ms DropTail

$ns duplex-link $n4 $n2 1Mb 10ms DropTail

  1. Simulate Data Transmission with CoC Tracking

You’ll mimic the transmission of data from n1 (sender) to n2 (receiver) via intermediate nodes (n3 and n4). Each intermediate node will log the packet’s journey and authenticate its integrity using a checksum or digital signature.

(A) Set Up Normal Traffic

You can start by configuring the normal UDP traffic flow from n1 to n2.

# Set up UDP traffic between n1 and n2

set udp1 [new Agent/UDP]

set null1 [new Agent/Null]

$ns attach-agent $n1 $udp1

$ns attach-agent $n2 $null1

$ns connect $udp1 $null1

# Create CBR (Constant Bit Rate) traffic generator

set cbr1 [new Application/Traffic/CBR]

$cbr1 set packetSize_ 512

$cbr1 set rate_ 1Mb

$cbr1 attach-agent $udp1

# Start normal traffic at 1.0 second

$ns at 1.0 “$cbr1 start”

(B) Track Packet Journey

Execute the Chain of Custody by tracking the packets when they travel over each node. You can replicate this by logging the packet’s journey and validating that each node has managed the packet appropriately.

Example of tracking packet flow through each node:

# Function to log packet journey through the network

proc log_packet_coc {packet_id source_node dest_node hop_count} {

puts “Packet $packet_id passed through $source_node on its way to $dest_node, hop count = $hop_count”

}

(C) Simulate CoC Validation

Each node will certify that the packet has not been tampered with, and it will join its identifier to the chain of custody log.

# Function to verify packet integrity (e.g., using a checksum)

proc verify_packet_integrity {packet_id checksum} {

set calculated_checksum [expr $packet_id * 1000]  ;# Dummy checksum calculation

if { $checksum == $calculated_checksum } {

puts “Packet $packet_id integrity verified”

return 1  ;# Return 1 if integrity is valid

} else {

puts “Packet $packet_id integrity failed”

return 0  ;# Return 0 if integrity is compromised

}

}

# Function to simulate handling the packet at each node

proc handle_packet {packet_id source_node dest_node hop_count checksum} {

global ns

# Log the packet’s chain of custody

log_packet_coc $packet_id $source_node $dest_node $hop_count

# Verify the packet integrity

if { [verify_packet_integrity $packet_id $checksum] } {

puts “Packet $packet_id forwarded to next hop”

} else {

puts “Packet $packet_id dropped due to failed integrity”

}

}

# Simulate handling of packet at each hop

$ns at 1.5 “handle_packet 1 n1 n3 1 1000”

$ns at 2.0 “handle_packet 1 n3 n4 2 1000”

$ns at 2.5 “handle_packet 1 n4 n2 3 1000”

  1. Simulate CoC Breach and Detection

A break in the Chain of Custody might happen if an intermediate node tampers with the packet. This can be simulated by changing the packet’s checksum at one of the nodes, which will start a failed integrity check at the next node.

Example of simulating a CoC breach at node n4:

# Simulate a CoC breach at n4 (tampering with the packet)

$ns at 2.5 “handle_packet 1 n4 n2 3 999”  ;# Use an incorrect checksum to simulate tampering

# The receiver or the next hop should detect the breach

  1. Implement CoC Log Storage

The log for each packet’s journey across the network is a crucial part of Chain of Custody preservation. You can save this log in a file or print it to the console.

Example of logging the CoC information:

# Open a file to store the Chain of Custody log

set coc_log [open coc_log.txt w]

# Log packet’s journey to the file

proc log_packet_to_file {packet_id source_node dest_node hop_count} {

global coc_log

puts $coc_log “Packet $packet_id passed through $source_node on its way to $dest_node, hop count = $hop_count”

}

# Log packet information to file

$ns at 1.5 “log_packet_to_file 1 n1 n3 1”

$ns at 2.0 “log_packet_to_file 1 n3 n4 2”

$ns at 2.5 “log_packet_to_file 1 n4 n2 3”

  1. Handle and Mitigate CoC Breaches

When a breach in the chain of custody is identified (like when integrity verification fails), you can take mitigation actions such as notifying network operators, dropping the packet, or redirecting traffic.

Example:

# Function to mitigate CoC breach

proc mitigate_coc_breach {packet_id} {

puts “Mitigating Chain of Custody breach for packet $packet_id”

# Take action such as alerting or rerouting

}

# Detect a breach and trigger mitigation

if { [verify_packet_integrity 1 999] == 0 } {

mitigate_coc_breach 1

}

  1. Run the Simulation

Once your script is ready, execute the simulation using NS2:

ns your_script.tcl

  1. Analyze the Results

After the simulation is done, evaluate the Chain of Custody logs to authenticate:

  • Whether each packet’s journey was tracked properly.
  • If any tampering or CoC breaches were identified.
  • Whether the system successfully eased the breaches.

You can also visualize the network activity using NAM (Network Animator) to monitor how packets are travel through each node.

  1. Extend the Simulation

You can extend this implementation by:

  • Including more nodes to the network to simulate more advanced scenarios.
  • Using cryptographic techniques (like digital signatures) to make sure more robust CoC verification.
  • Implementing automated responses for managing breaches like isolating compromised nodes or redirecting traffic.
  • Logging more details in the Chain of Custody in timestamps, node IDs, and extra metadata.

Make use of the given expounded technique to get to learn and be able to implement the Network Chain of Custody (CoC) Preservation using ns2 simulator. We provide structured procedure that also has examples with snippet codes to help you and you can extend the simulation for further enhancements.

Get innovative ideas and topics for the Network CoC Preservation project, focusing on scenarios developed by our experts. These scenarios emphasize tracking and logging packet management, ensuring their integrity at each hop, ultimately delivering optimal results.