How to Implement IP Protocols in NS2

 

To implement the IP (Internet Protocol) in Network Simulator 2 (ns2), we need to generate a simulation script that has an IP which is used for routing and addressing inside the network. It inherently uses IP for interaction amongst the nodes, however you can basically set up and replicate different IP-based environment. This manual will help you to set up the basic IP-based simulation:

Step-by-Step Implementation:

Step 1: Install NS2

Make certain to install the ns2 and checks if it is properly configured based on your operating system.

Step 2: Create an IP-Based Simulation Script

  1. Create a new Tcl script: Open a text editor and design a new file such as, ip_example.tcl.
  2. Set up the simulation environment: Stating by stating the simulator, generating the network topology, and setting up the parameters for your IP-based simulation.

# Create a simulator object

set ns [new Simulator]

# Define options for the simulation

set val(chan)   Channel/WirelessChannel    ;# Channel type

set val(prop)   Propagation/TwoRayGround   ;# Propagation model

set val(netif)  Phy/WirelessPhy            ;# Network interface type

set val(mac)    Mac/802_11                 ;# MAC type

set val(ifq)    Queue/DropTail/PriQueue    ;# Interface Queue type

set val(ll)     LL                         ;# Link layer type

set val(ant)    Antenna/OmniAntenna        ;# Antenna type

set val(ifqlen) 50                         ;# Max packet in ifq

set val(nn)     5                          ;# Number of mobile nodes

set val(x)      500                        ;# X dimension of topography

set val(y)      500                        ;# Y dimension of topography

set val(stop)   10.0                       ;# Simulation time

# Initialize the topology object

set topo [new Topography]

$topo load_flatgrid $val(x) $val(y)

# Create the God object

create-god $val(nn)

# Configure the nodes

$ns node-config -llType $val(ll) \

-macType $val(mac) \

-ifqType $val(ifq) \

-ifqLen $val(ifqlen) \

-antType $val(ant) \

-propType $val(prop) \

-phyType $val(netif) \

-channelType $val(chan) \

-topoInstance $topo \

-agentTrace ON \

-routerTrace ON \

-macTrace ON \

-movementTrace ON

  1. Create nodes and define mobility:

# Create nodes

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

set node_($i) [$ns node]

$node_($i) random-motion 0

}

# Define node movement (Optional for mobile nodes)

$node_(0) set X_ 50.0

$node_(0) set Y_ 50.0

$node_(0) set Z_ 0.0

$node_(1) set X_ 100.0

$node_(1) set Y_ 100.0

$node_(1) set Z_ 0.0

 

# (Add more movement patterns or use mobility models if needed)

  1. Setup traffic sources and routing agents:

You can build various agents to send and obtain data over the IP network, since NS2 is IP-based by default. You can use UDP, TCP, and other IP-based agents.

# Setup UDP agent and attach it to node 0

set udp [new Agent/UDP]

$ns attach-agent $node_(0) $udp

# Setup CBR (Constant Bit Rate) application to generate traffic

set cbr [new Application/Traffic/CBR]

$cbr attach-agent $udp

$cbr set packetSize_ 512

$cbr set interval_ 0.1

$cbr start

# Setup Null agent (sink) on node 1

set null [new Agent/Null]

$ns attach-agent $node_(1) $null

# Connect the agents

$ns connect $udp $null

  1. Setup simulation end:

# Define simulation end time

$ns at $val(stop) “stop”

$ns at $val(stop) “$ns nam-end-wireless $val(stop)”

$ns at $val(stop) “exit 0”

proc stop {} {

global ns tracefile namfile

$ns flush-trace

close $tracefile

close $namfile

}

# Run the simulation

$ns run

Step 3: Run the Simulation

  1. Save the Tcl script (ip_example.tcl).
  2. Open a terminal and direct to the directory where you stored the Tcl script.
  3. Run the simulation using the given command:

ns ip_example.tcl

This will produce trace files and optionally a network animation file (if allowed in your script).

Step 4: Analyze the Results

You can use tools like awk, perl, or other scripting languages to process the trace files generated by NS2 to evaluate the performance and characteristics of IP-based communication in your network.

Step 5: Visualize the Results (Optional)

You can visualize the simulation by enforcing the network animator (NAM) in your script:

nam ip_example.nam

This will open the NAM window, where you can see the network topology and the actions of the IP protocol during the simulation.

Additional Considerations:

  • IP Address Configuration: In NS2, IP addresses are inevitably allocated to nodes. You can manually design them if required by utilizing the node’s IP stack, however this is hardly essential for basic simulations.
  • Routing Protocols: While NS2 uses IP, you can associate it with different routing protocols like AODV, DSR, or a basic static routing. For pure IP simulations, you might not need to develop a particular routing protocol, depending rather than on the built-in forwarding features.

From this demonstration, you can now understand the implementation concept of Network IP Addressing in OMNeT++ environment and also learned how it defines the nodes, traffic sources, mobility and routing agents with samples. We offer project network analysis, so you can count on us to help with your project. If you want to implement Interior Protocol in NS2, check out ns2project.com. We have great project topics to share with you. We work on all kinds of nodes for your projects, so keep in touch with us for the best outcomes.