How to Calculate Network Node degree in NS2

To calculate the node degree within NS2, we require to determine the number of direct connections (links), which each node has to other nodes within the network. The node degree is a significant metric for estimating the topology and connectivity of a network. Now, we provide simple calculation guide to computing the Node degree in NS2:

Steps to Calculate Node Degree in NS2

  1. Set up the Simulation in NS2

Initially, make a simulation with nodes and links among them in NS2. Below is an example of a basic network configuration in a .tcl file:

# Create NS2 simulator instance

set ns [new Simulator]

# Define nodes

set n0 [$ns node]

set n1 [$ns node]

set n2 [$ns node]

set n3 [$ns node]

# Create links between nodes

$ns duplex-link $n0 $n1 1Mb 10ms DropTail

$ns duplex-link $n1 $n2 1Mb 10ms DropTail

$ns duplex-link $n2 $n3 1Mb 10ms DropTail

$ns duplex-link $n3 $n0 1Mb 10ms DropTail

# Simulation end

$ns at 5.0 “finish”

proc finish {} {

global ns

$ns flush-trace

exit 0

}

# Run simulation

$ns run

In this instance, there are four nodes and every single node is connected to its neighbouring nodes.

  1. Collect Trace Data

When the simulation runs then it generates a trace file (e.g., out.tr), in which all network events, like packet sending, receiving, and link creations, are recorded. We will be focused on the part of the trace, which logs the creation of links among the nodes.

  1. Extract Link Information

To compute the node degree, we will require to parse the trace file to discover which nodes are related to each other. This data can find in the simulation setup, however we may also extort it from the trace file if we have dynamically made links.

If we require to directly compute the node degree rely on the established connections, now how we can process it AWK or Python.

Example Trace Line for Link Creation:

If the trace file logs the creation of duplex links then it may look like this:

+ 0.000000 0 1 tcp 40 —— 1 0.0 0.0 0.0

+ 0.000000 1 2 tcp 40 —— 1 0.0 0.0 0.0

+ 0.000000 2 3 tcp 40 —— 1 0.0 0.0 0.0

+ 0.000000 3 0 tcp 40 —— 1 0.0 0.0 0.0

Each line denotes a link among the nodes (0 -> 1, 1 -> 2, etc.).

  1. Process Trace File to Calculate Node Degree

We can be used a script to count the number of connections for each node.

Using AWK:

awk ‘

{

if ($1 == “+”) {

node_from[$3]++;

node_to[$4]++;

}

}

END {

for (node in node_from) {

print “Node ” node ” has degree ” node_from[node] + node_to[node];

}

}’ out.tr

This AWK script processes the trace file by:

  • Counting the number of times a node emerges as a source ($3) or destination ($4) in the trace file.
  • Finally, it prints the degree of each node.

Using Python:

Otherwise, we can be used the Python to analyse the trace file and estimate the node degree:

node_degree = {}

with open(“out.tr”, “r”) as f:

for line in f:

data = line.split()

if data[0] == “+”:

# Increment degree for the source node

src_node = int(data[2])

dst_node = int(data[3])

if src_node in node_degree:

node_degree[src_node] += 1

else:

node_degree[src_node] = 1

# Increment degree for the destination node

if dst_node in node_degree:

node_degree[dst_node] += 1

else:

node_degree[dst_node] = 1

# Print the node degrees

for node, degree in node_degree.items():

print(f”Node {node} has degree {degree}”)

This Python script reads the trace file, divides each line into fields, and verifies if the line denotes a link creation (based on the + symbol). Then it increases the degree count for both the origin and end nodes.

  1. Interpret the Results

After processing the trace file:

  • Node degree: The outcomes expresses each node has how many direct connections. If a node is connected to three other nodes then its degree is 3.
  • The higher the degree, the more connected the node is.

Example Output:

For the instance .tcl file above, the output can be:

Node 0 has degree 2

Node 1 has degree 2

Node 2 has degree 2

Node 3 has degree 2

It means each node has two direct connections, as it is connected to its instant neighbours in a circular topology.

Summary

To evaluate the node degree in NS2:

  1. Configure the simulation and make a nodes with links.
  2. Gather trace data.
  3. Process the trace file using AWK, Python, or same tools to count each node has how many connections.
  4. The out coming node degree provides each node has the number of direct connections.

Here, we had followed the simplified process with examples and summary are helps to know the concepts and the way how to compute the Network Node degree within NS2 tool. Also we will delivered more valuable insights on this topic based on your requirements.

We’re here to help you with your performance analysis! Just let us know the details of what you need. If you have questions about your Network Node degree in the NS2 tool, reach out to us. We can also help you come up with cool project ideas and topics. Our focus is on network topology and connectivity.