How to Implement Network Intent in NS2

To implement the Network Intent in NS2, it denotes a high-level abstraction with network administrators state what they want the network to accomplish (the “intent”) and network management system systematically interprets these intents into actionable set ups and policies. Intent-based networking (IBN) concentrates on predefined goals instead of single configurations or low-level policies.

In NS2, you can replicate Network Intent by generating high-level goals like making certain low latency for particular traffic variants or dynamically adjusting bandwidth to enhance throughput, and then translating those intents into certain rules (e.g., traffic prioritization, dynamic routing, or queue management) that the simulation will enforce.

Steps to Implement Network Intent in NS2:

  1. Define the Network Topology: Set up nodes and links that indicate the network infrastructure.
  2. Specify Intents: State high-level goals like enhancing bandwidth, less latency for specific kinds of traffic, or making sure load balancing.
  3. Translate Intents into Rules: Scripts are used to execute these goals by dynamically altering network parameters like queue limits, routing decisions, and bandwidth distribution.
  4. Monitor and Enforce: Track network performance and dynamically adjust parameters during the simulation to make certain that the intent is met.
  5. Analyze Results: Gather and assess metrics like throughput, latency, and packet loss to assess how well the intent was fulfilled.

Example: Simulating Network Intent in NS2

In this sample, we’ll state two intents:

  • Intent 1: Make sure that video traffic gets a higher priority than file transfers.
  • Intent 2: Dynamically balance the traffic load amongst two routers to making certain optimal bandwidth consumption.

Example TCL Script for Simulating Network Intent:

# Create a new NS2 simulator instance

set ns [new Simulator]

# Define output trace file for logging events

set tracefile [open network_intent.tr w]

$ns trace-all $tracefile

# Define animation file for NAM (optional)

set namfile [open network_intent.nam w]

$ns namtrace-all $namfile

# Create network nodes: Clients, two routers, and a server

set client1 [$ns node]   # Client 1 (file transfers)

set client2 [$ns node]   # Client 2 (video streaming)

set router1 [$ns node]   # Router 1

set router2 [$ns node]   # Router 2

set server [$ns node]    # Server

# Create duplex links between nodes

$ns duplex-link $client1 $router1 10Mb 10ms DropTail

$ns duplex-link $client2 $router1 10Mb 10ms DropTail

$ns duplex-link $router1 $router2 50Mb 10ms DropTail

$ns duplex-link $router2 $server 100Mb 10ms DropTail

# Intent 1: Prioritize video traffic over file transfer traffic

proc enforce_intent_1 {} {

global ns client1 client2 router1

puts “Enforcing Intent 1: Prioritizing video traffic over file transfers…”

# Increase queue limit for Client 2 (video streaming) to give it higher priority

$ns queue-limit $client2 $router1 100

$ns queue-limit $client1 $router1 50

}

# Intent 2: Dynamically balance traffic load between Router 1 and Router 2

proc enforce_intent_2 {} {

global ns client1 client2 router1 router2

puts “Enforcing Intent 2: Load balancing between Router 1 and Router 2…”

# Dynamically adjust traffic flows based on traffic load

if {[rand] < 0.5} {

puts “Routing traffic from Client 2 through Router 1”

$ns at 2.0 “$ns connect $client2 $router1”

} else {

puts “Routing traffic from Client 2 through Router 2”

$ns at 2.0 “$ns connect $client2 $router2”

}

}

# Define traffic for Client 1 (TCP – File Transfer)

set tcp_client1 [new Agent/TCP]

$ns attach-agent $client1 $tcp_client1

set tcp_sink [new Agent/TCPSink]

$ns attach-agent $server $tcp_sink

$ns connect $tcp_client1 $tcp_sink

set ftp_client1 [new Application/FTP]

$ftp_client1 attach-agent $tcp_client1

# Define traffic for Client 2 (UDP – Video Streaming)

set udp_client2 [new Agent/UDP]

$ns attach-agent $client2 $udp_client2

set udp_sink [new Agent/Null]

$ns attach-agent $server $udp_sink

$ns connect $udp_client2 $udp_sink

set cbr_client2 [new Application/Traffic/CBR]

$cbr_client2 attach-agent $udp_client2

$cbr_client2 set packetSize_ 1000

$cbr_client2 set rate_ 2Mb

$cbr_client2 set interval_ 0.01

# Schedule the start of traffic

$ns at 0.5 “$ftp_client1 start”

$ns at 0.5 “$cbr_client2 start”

# Enforce intents dynamically during the simulation

$ns at 1.0 “enforce_intent_1”

$ns at 2.0 “enforce_intent_2”

# Schedule the stop time for traffic

$ns at 4.0 “$ftp_client1 stop”

$ns at 4.0 “$cbr_client2 stop”

# End the simulation at 5.0 seconds

$ns at 5.0 “finish”

# Define a finish procedure to close trace files and execute NAM for visualization

proc finish {} {

global ns tracefile namfile

$ns flush-trace

close $tracefile

close $namfile

exec nam network_intent.nam &

exit 0

}

# Run the simulation

$ns run

Explanation of the Script:

  1. Network Topology:
    • We configure a simple topology with two clients, two routers, and a server. One client is used for file transfers (TCP) and the other for video streaming (UDP).
  2. Intent 1 (Prioritizing Video Traffic):
    • The goal is to give higher priority to video streaming traffic over file transfers. We maximize the queue limit for Client 2 (video traffic) to 100 and decrease the queue limit for Client 1 (file transfers) to 50. This make sure that more packets from Client 2 will be processed, giving preference to video streaming.
  3. Intent 2 (Dynamic Load Balancing):
    • The second goal is to balance the traffic load amongst Router 1 and Router 2. The script uses a random decision to route Client 2’s traffic through either Router 1 or Router 2, simulating a dynamic load-balancing decision.
  4. Traffic Simulation:
    • Client 1 delivers TCP traffic (file transfers via FTP) to the server.
    • Client 2 delivers UDP traffic (video streaming via CBR) to the server.
  5. Intent Enforcement:
    • At 1.0 seconds, Intent 1 (prioritizing video traffic) is enforced by modifying queue limits.
    • At 2.0 seconds, Intent 2 (dynamic load balancing) is enforced by randomly altering routing for Client 2.
  6. Simulation Control:
    • The traffic begins at 0.5 seconds and terminates at 4.0 seconds. The intents are enforced dynamically during the simulation.
  1. Analyzing the Impact of Intents

The trace file (network_intent.tr) will log the impacts of the network intents on traffic flow like how prioritizing video traffic impacts throughput and latency for both kinds of traffic.

  1. a) Throughput Measurement:

You can compute the throughput for TCP traffic (file transfers) using the below command:

awk ‘$1 == “r” && $4 == “tcp” { total_bytes += $5 } END { print “Throughput: “, total_bytes/5, “bytes/sec” }’ network_intent.tr

This command estimate the total bytes obtained over the simulation and give the average throughput for Client 1.

  1. b) Latency Measurement:

To calculate the latency for TCP traffic (file transfers), use the given command:

awk ‘

/^s/ && $4 == “tcp” { sent[$6] = $2 }

/^r/ && $4 == “tcp” { if ($6 in sent) { total_delay += ($2 – sent[$6]); total_packets++ } }

END { print “Average Latency: “, total_delay/total_packets, “seconds” }’ network_intent.tr

This script calculates the average delay experienced by TCP packets amongst sending and receiving.

  1. Advanced Intent Management Features

To optimize intent-related networking in NS2, you can:

  • QoS-Based Intent: Execute additional intents that make sure particular Quality of Service (QoS) metrics are met for certain traffic like maintaining minimal throughput or jitter for real-time applications.
  • Security-Based Intent: Configure security policies as well as restricting access to particular nodes or applying firewalls dynamically, as part of the intent.
  • Feedback Loops: Incorporate real-time monitoring of network performance like throughput or latency, to continuously modify the configuration in order to meet the defined goals.

This procedure has covered the overall demonstration which is essential to know before implementing the Network Intent into the simulation using ns2 tool. You can include their advanced features into the simulation for future optimization. We will offer the additional records, if needed.

To implement Network Intent using the NS2 tool, please contact us for the best guidance available. Our team is fully equipped with the necessary resources to provide you with excellent support and timely delivery.