How to Start Wide Area Networks Projects Using NS2

To start Wide Area Networks (WAN) projects in NS2 (Network Simulator 2), we can follow this detailed procedure:

Steps to Start Wide Area Networks Projects in NS2

  1. Understand NS2 Basics
  • What is NS2? NS2 is a discrete event simulator supports for wired and wireless networks to create it which is appropriate to replicating the WAN scenarios.
  • Wide Area Networks (WAN): WAN projects have to replicate long-distance network communication, with routers, links, congestion control, routing mechanisms, and TCP/IP, MPLS, and BGP protocols.
  • Key Components for WAN Simulations:
    • Nodes that denote the routers, switches, hosts.
    • Links are connected with high-latency, low-bandwidth connections normally utilised in WANs.
    • Routing protocols such as RIP, OSPF, MPLS, and BGP.
  1. Install NS2
  • Installation Steps:

sudo apt-get update

sudo apt-get install ns2

  • Test Installation: Execute the below command line:

ns

If % occurs then installation is effectively functioned.

  1. Define Your WAN Scenario
  • Topology Design:
    • Make a network topology that has structure like star, tree, or mesh topology.
    • Find out the volume of nodes, routers, and links.
    • Allocate the link features such as delay, bandwidth.
  • Routing Protocols:
    • Make use of routing protocols as RIP, OSPF, or MPLS.
    • Execute the routing protocols for measuring its performance through WAN.
  • Traffic Models:
    • Make traffic patterns with the support of TCP, UDP, FTP, or CBR protocols.
  1. Create a Basic WAN Simulation in NS2

Below is an instance Tcl script for a simple WAN scenario:

# Create Simulator

set ns [new Simulator]

# Define Trace File for Output

set tracefile [open out.tr w]

$ns trace-all $tracefile

# Define NAM File for Visualization

set namfile [open out.nam w]

$ns namtrace-all $namfile

# Create Nodes

set node1 [$ns node]

set node2 [$ns node]

set node3 [$ns node]

# Create Links (WAN-specific properties)

$ns duplex-link $node1 $node2 1Mb 50ms DropTail

$ns duplex-link $node2 $node3 512Kb 100ms DropTail

# Attach Traffic Sources

# TCP Connection

set tcp [new Agent/TCP]

$ns attach-agent $node1 $tcp

set sink [new Agent/TCPSink]

$ns attach-agent $node3 $sink

$ns connect $tcp $sink

# Traffic Generator (FTP over TCP)

set ftp [new Application/FTP]

$ftp attach-agent $tcp

$ftp start

# Schedule Simulation End

$ns at 10.0 “finish”

proc finish {} {

global ns tracefile namfile

$ns flush-trace

close $tracefile

close $namfile

exec nam out.nam &

exit 0

}

# Run Simulation

$ns run

  1. Configure WAN-Specific Parameters
  • Link Properties:
    • Allocate the link properties like bandwidth, propagation delay, and queue types that exposing in real WAN scenarios.

$ns duplex-link $node1 $node2 10Mb 100ms DropTail

  • Routing Protocols: Execute the immobile or dynamic routing:
    • Static Routing: Describe the static routes.
    • Dynamic Routing: It is support to utilise the built-in protocols such as RIP, OSPF. For instance: It allows OSPF for dynamic routing.
  1. Analyze and Visualize Results
  • Trace File Analysis: Examine the trace file (out.tr) for estimating the performance parameters such as:
    • Packet loss
    • End-to-end delay
    • Throughput
  • Graphical Analysis: Visualize the outcomes to utilise external tools such as Gnuplot or Python.
  • NAM Visualization: Utilise NAM file for envisioning the node communications:

nam out.nam

  1. Extend the WAN Project
  • Add Advanced Protocols:
    • MPLS: For traffic engineering, we can apply the MPLS protocols within WANs.
    • BGP: Replicate inter-domain routing.
  • Introduce Scalability:
    • Mimic a larger WAN including additional nodes and complex topologies for scalability.
  • Apply QoS Policies:
    • We need to execute the traffic prioritization and queue management using QoS strategies like RED, FQ.
  • Evaluate Performance:
    • We equate performance with various routing protocols like OSPF vs. RIP.
    • Focus on the effect of network congestion and failures.
  1. Experiment with WAN Scenarios
  • Latency Impact: Change the link delays for measuring the performance within high-latency scenarios.
  • Congestion Control: Learn the TCP congestion control mechanisms behavior to avoid blockage.
  • Redundancy and Resilience: Replicate the link or node failures and then estimating routing retrieval.
  1. Document the Results
  • It provides comprehensive report or documentation that contains:
    • We define the project goals
    • Create network topology
    • Estimate the simulation metrics
    • Analyse the performance parameters
    • Observations and conclusions
  1. Advanced Topics for WAN Projects
  • Software-Defined WAN (SD-WAN): Execute the centralized traffic management.
  • Content Delivery Networks (CDNs): Replicate data distribution through the nodes.
  • WAN Optimization: Examine the mechanisms such as compression and caching.
  • Security in WANs: Mimic attacks and defense approaches within WANs.

With NS2 simulation environment, we conducted a detailed simulation that helps you to replicate and examine the Wide Area Networks Projects and provided advanced topics for this project. Furthermore, we will also offer innovative specifies about WANs projects in another manual.