How to Start Physical Layer Projects Using NS2

To stimulate a Physical Layer project in NS2 has concentrate on the replication of communication network protocols through physical communication features like as signal broadcast, interference and noise. Though NS2 mainly it functions for high layer such as network and transport for physical layer has replicate the capacities in design for wireless network efficiently.

Steps to Start Physical Layer Projects Using NS2

Here’s how you can get started:

1. Understand the Physical Layer in NS2

• Key Components:
  • Wireless Channel: It designs for the signal propagation.
  • Propagation Models: The broadcast model has involves the free-space, two-Ray Ground, or shadowing models.
  • Transmission Power and Noise: The communication replicates the signal strength and interference.
  • Antenna Models: Omni-directional or directional antennas.
• Focus Areas for Projects:
  • Intrusion and Signal strength.
  • Bit Error Rate (BER) below various environments.
  • Impact of transmission for range and power.
  • It associates the broadcast design.

2. Set Up NS2

1. Install NS2: Install NS2 with wireless extensions:

sudo apt-get install ns2

1. Verify Installation: Run:

ns

If the NS2 shell opens, the installation is successful.

3. Define Your Project Goals

Choose the concentrate:

• Examine on how the transmission power impact of network performance.
• Study of impact the broadcast design on throughput and packet loss.
• Design the intrusion and noise in wireless networks.

4. Create a Basic Simulation Script

Write a TCL script has replicate the wireless nodes interacting with the physical layer.

Example TCL Script for Physical Layer Simulation:

# Create a new simulator instance

set ns [new Simulator]

# Open trace and NAM files

set tracefile [open phy_layer.tr w]

$ns trace-all $tracefile

set namfile [open phy_layer.nam w]

$ns namtrace-all-wireless $namfile 500 500

# Set up the wireless network parameters

set topo [new Topography]

$topo load_flatgrid 500 500  ;# Define simulation area

# Configure node parameters

$ns node-config -adhocRouting DSR \

-llType LL \

-macType Mac/802_11 \

-ifqType Queue/DropTail/PriQueue \

-ifqLen 50 \

-antType Antenna/OmniAntenna \

-propType Propagation/TwoRayGround \

-phyType Phy/WirelessPhy \

-channelType Channel/WirelessChannel \

-topoInstance $topo

# Create wireless nodes

set n0 [$ns node]

set n1 [$ns node]

set n2 [$ns node]

# Set initial positions of nodes

$n0 set X_ 100

$n0 set Y_ 200

$n0 set Z_ 0

$n1 set X_ 200

$n1 set Y_ 300

$n1 set Z_ 0

$n2 set X_ 300

$n2 set Y_ 400

$n2 set Z_ 0

# Define a TCP traffic source

set tcp0 [new Agent/TCP]

$ns attach-agent $n0 $tcp0

set sink0 [new Agent/TCPSink]

$ns attach-agent $n2 $sink0

$ns connect $tcp0 $sink0

# Generate FTP traffic over TCP

set ftp [new Application/FTP]

$ftp attach-agent $tcp0

$ns at 0.5 “$ftp start”

$ns at 4.5 “$ftp stop”

# Run the simulation

$ns at 5.0 “finish”

proc finish {} {

global ns tracefile namfile

$ns flush-trace

close $tracefile

close $namfile

exec nam phy_layer.nam &

exit 0

}

$ns run

5. Experiment with Physical Layer Parameters

1. Propagation Models: Variation the -propType parameter for associate the design:
   • Free Space:

-propType Propagation/FreeSpace

1. • Two-Ray Ground:

-propType Propagation/TwoRayGround

1. • Shadowing:

-propType Propagation/Shadowing

1. Transmission Power: Change the transmission power in the Phy/WirelessPhy component:

Phy/WirelessPhy set Pt_ 0.2818  ;# Transmission power in watts

1. Antenna Models: Use the model for directional antennas in advanced projects:

-antType Antenna/DirectionalAntenna

6. Run the Simulation

1. Store the script as phy_layer_simulation.tcl.
2. Implement:

ns phy_layer_simulation.tcl

1. Envision for the replication of NAM:

nam phy_layer.nam

7. Analyze Simulation Results

1. Trace File Analysis: Excerpt metrics like as packet delivery ratio, throughput, and latency from the .tr file using tools such as AWK, Python, or MATLAB.
2. Key Metrics:
   • Signal-to-Noise Ratio (SNR).
   • Packet loss due to interference.
   • Energy consumption of nodes.

8. Experiment with Advanced Scenarios

1. Interference: Establish the several transmitters and study the interference:

set tcp1 [new Agent/TCP]

$ns attach-agent $n1 $tcp1

set sink1 [new Agent/TCPSink]

$ns attach-agent $n2 $sink1

$ns connect $tcp1 $sink1

1. Mobility: Simulate node mobility:

$ns at 1.0 “$n0 setdest 400 400 10.0”

$ns at 2.0 “$n1 setdest 100 100 15.0”

1. Noise and BER: Alter the configure of noise for analysis the Bit Error Rate (BER):

Phy/WirelessPhy set RxThresh_ 1.0e-10  ;# Reception threshold

Phy/WirelessPhy set CSThresh_ 1.0e-10 ;# Carrier sense threshold

9. Document Findings

Include:

• Objectives: What features for examine the physical layer.
• Simulation Setup: Then methodology analyse for network topology, parameters, and broadcast models used.
• Results: Then simulation performance gives the parameter metrices such as graphs and metrics for sample throughput, latency.
• Insights: Explanations for the effect of physical layer features.

10. Extend the Project

1. Hybrid Propagation Models: Associate the broadcast design for instance Two-Ray Ground with Shadowing.
2. Power Control: It replicate the dynamic power change for energy effectiveness.
3. QoS Analysis: Analysis on how physical layer environments impact for the QoS metrics in upper layers.

We uncover the overall information which will understand the concepts and techniques that will help you to give some unique ideas to replicate the physical layer projects using the tool of ns2. For further inquiries about this project, a separate manual will be provided.