How to Simulate Fully Connected Topology Projects Using NS2

To simulate Fully Connected Topology in ns2 has needs to follow numerous approaches and it is defined as a network structure in which every node is natively associated to every other node in the network. This topology is helpful for reviewing environment in which multiple nodes can interact with each other simultaneously, without depending on intermediary nodes.

Here’s how to simulate a Fully Connected Topology in NS2:

Steps to Simulate Fully Connected Topology Projects in NS2

1. Set up NS2 Environment:

Make sure that NS2 is installed and configured appropriately on the system. We will write a TCL script to replicate the Fully Connected Topology.

2. Understanding Fully Connected Topology:

• In a Fully Connected Topology, each node has a direct link to every other node in the network. These resources that if there are n nodes, there are n (n-1)/2 links in the network.
• This topology makes sure the highest level of redundancy and fault tolerance; however it also needs a lot of resources to handle the numerous links.

3. Create a TCL Script for Fully Connected Topology:

Let’s generate a Fully Connected Topology with 4 nodes (we can upsurge the number of nodes as needed):

# Create a new simulator instance

set ns [new Simulator]

# Open a NAM trace file for visualization

set nf [open out.nam w]

$ns namtrace-all $nf

# Create nodes (fully connected)

set n0 [$ns node]

set n1 [$ns node]

set n2 [$ns node]

set n3 [$ns node]

# Create duplex links to form the Fully Connected Topology

$ns duplex-link $n0 $n1 10Mb 10ms DropTail

$ns duplex-link $n0 $n2 10Mb 10ms DropTail

$ns duplex-link $n0 $n3 10Mb 10ms DropTail

$ns duplex-link $n1 $n2 10Mb 10ms DropTail

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

$ns duplex-link $n2 $n3 10Mb 10ms DropTail

# Attach UDP agents to the nodes

set udp0 [new Agent/UDP]

$ns attach-agent $n0 $udp0

set udp1 [new Agent/UDP]

$ns attach-agent $n1 $udp1

set udp2 [new Agent/UDP]

$ns attach-agent $n2 $udp2

set udp3 [new Agent/UDP]

$ns attach-agent $n3 $udp3

# Create Null agents for receiving traffic

set null0 [new Agent/Null]

$ns attach-agent $n1 $null0

set null1 [new Agent/Null]

$ns attach-agent $n2 $null1

set null2 [new Agent/Null]

$ns attach-agent $n3 $null2

# Connect the UDP agents to the Null agents (simulating traffic flow between nodes)

$ns connect $udp0 $null0

$ns connect $udp1 $null1

$ns connect $udp2 $null2

# Create a Constant Bit Rate (CBR) traffic source and attach it to the UDP agents

set cbr0 [new Application/Traffic/CBR]

$cbr0 attach-agent $udp0

$cbr0 set packetSize_ 512    ;# Packet size of 512 bytes

$cbr0 set rate_ 100Kb        ;# Data rate of 100Kb

set cbr1 [new Application/Traffic/CBR]

$cbr1 attach-agent $udp1

$cbr1 set packetSize_ 512

$cbr1 set rate_ 100Kb

set cbr2 [new Application/Traffic/CBR]

$cbr2 attach-agent $udp2

$cbr2 set packetSize_ 512

$cbr2 set rate_ 100Kb

# Schedule the CBR traffic to start and stop

$ns at 1.0 “$cbr0 start”

$ns at 1.5 “$cbr1 start”

$ns at 2.0 “$cbr2 start”

$ns at 5.0 “$cbr0 stop”

$ns at 5.5 “$cbr1 stop”

$ns at 6.0 “$cbr2 stop”

# End the simulation at 7 seconds

$ns at 7.0 “finish”

proc finish {} {

global ns nf

$ns flush-trace

close $nf

exec nam out.nam &

exit 0

}

# Run the simulation

$ns run

4. Explanation of the Code:

• Nodes: Four nodes (n0, n1, n2, and n3) are generated to replicate the fully connected topology.
• Links: Duplex links are configures among every pair of nodes that constructed a fully connected structure. In this instance, there are a total of 6 links among the 4 nodes (since for 4 nodes, 4(4-1)/2 = 6).
• UDP Agents: UDP agents are generated and attached to each node. Null agents are utilized at the receiving ends to perform as traffic sinks.
• CBR Traffic: A Constant Bit Rate (CBR) traffic generator is attached to the UDP agents to replicate traffic flow among the nodes. The traffic initiate at different times for each node and ends at certain times.
• Simulation End: The simulation is scheduled to end after 7 seconds, and the outcomes are saved in a .nam file for visualization.

5. Run the Simulation:

1. Save the script as fully_connected.tcl.
2. Open a terminal and navigate to the folder in which the script is saved.
3. Execute the simulation using the following command:

ns fully_connected.tcl

1. The output will creates out.nam file that can be opened using the Network Animator (NAM) tool.

6. Visualization in NAM:

• After the simulation executes, we can envision the fully associated topology using NAM. We should see all nodes associated to each other, and traffic will flow among the nodes based on the CBR scheduling.

7. Customization and Enhancements:

• TCP Traffic: we can replace the UDP agents with TCP agents to replicate reliable data transmission. For example:

set tcp0 [new Agent/TCP]

$ns attach-agent $n0 $tcp0

set sink0 [new Agent/TCPSink]

$ns attach-agent $n1 $sink0

$ns connect $tcp0 $sink0

• More Nodes: we can build-up the amount of nodes and links to replicate a larger fully associated network. Remember that the number of links wills upsurges considerably as the number of nodes grows.
• Performance Metrics: We can insert tracing to evaluate parameters such as packet loss, delay, and throughput. For example:

set tracefile [open trace.tr w]

$ns trace-all $tracefile

• Different Bandwidth/Delay: We can research with different link metrics to replicate numerous various conditions such as higher bandwidth or lower delay.

8. Performance Analysis:

To evaluate the performance of the fully connected topology, that can:

• Evaluate throughput by measuring the number of data successfully routed among nodes.
• Assess latency (delay) among the nodes as data traverses the network.
• Monitor packet loss in instance of network congestion or bandwidth boundaries.

This procedure offered the step-by-step guide to help you implement Fully Connected Topology in ns2 environment and provides from the basic set up to analysing the results like configuration of network topology and initializing to communicate with multiple nodes. We will provide any details regarding this manual, if needed. Our team delivers comparative analysis results tailored to your projects. With our expertise in intermediary nodes, we encourage you to stay connected for optimal results. For assistance in simulating Fully Connected Topology Projects using the NS2 tool, visit phdprime.com. If you require robust research support and simulation assistance, our specialists are ready to help.