Classful addressing (Class A, B, C) in Computer Networks - Mini Project: Build & Apply

Understanding Classful Addressing (Class A, B, C)

📖 Scenario: You are learning about how IP addresses were originally divided into classes to organize networks. This helps in understanding how computers identify each other on a network.

🎯 Goal: Create a simple reference table that shows the ranges and key features of Class A, Class B, and Class C IP addresses.

📋 What You'll Learn

Create a dictionary called ip_classes with keys 'Class A', 'Class B', and 'Class C'.

Each key should map to another dictionary with keys: range, default_subnet_mask, and max_hosts.

Add a variable called total_classes that counts how many classes are in ip_classes.

Create a list called class_names that contains the names of the classes from ip_classes.

Add a final statement that adds a new key description to each class dictionary with a short explanation.

💡 Why This Matters

🌍 Real World

Understanding classful addressing helps in grasping how networks were originally organized and how IP addresses are structured.

💼 Career

Network administrators and IT professionals use this knowledge to design and troubleshoot IP networks.

1

Create the IP classes dictionary

Create a dictionary called ip_classes with these exact keys and values:
'Class A' maps to {'range': '1.0.0.0 - 126.255.255.255', 'default_subnet_mask': '255.0.0.0', 'max_hosts': 16777214},
'Class B' maps to {'range': '128.0.0.0 - 191.255.255.255', 'default_subnet_mask': '255.255.0.0', 'max_hosts': 65534},
and 'Class C' maps to {'range': '192.0.0.0 - 223.255.255.255', 'default_subnet_mask': '255.255.255.0', 'max_hosts': 254}.

Computer Networks

# Create the ip_classes dictionary with Class A, B, and C details
# Your code here

Need a hint?

Use a dictionary with keys 'Class A', 'Class B', and 'Class C'. Each key maps to another dictionary with the specified keys and values.

2

Add total_classes variable

Add a variable called total_classes that stores the number of classes in the ip_classes dictionary.

Computer Networks

ip_classes = {
    'Class A': {'range': '1.0.0.0 - 126.255.255.255', 'default_subnet_mask': '255.0.0.0', 'max_hosts': 16777214},
    'Class B': {'range': '128.0.0.0 - 191.255.255.255', 'default_subnet_mask': '255.255.0.0', 'max_hosts': 65534},
    'Class C': {'range': '192.0.0.0 - 223.255.255.255', 'default_subnet_mask': '255.255.255.0', 'max_hosts': 254}
}
# Add total_classes variable below
# Your code here

Need a hint?

Use the len() function to count the number of keys in ip_classes.

3

Create list of class names

Create a list called class_names that contains the keys (class names) from the ip_classes dictionary.

Computer Networks

ip_classes = {
    'Class A': {'range': '1.0.0.0 - 126.255.255.255', 'default_subnet_mask': '255.0.0.0', 'max_hosts': 16777214},
    'Class B': {'range': '128.0.0.0 - 191.255.255.255', 'default_subnet_mask': '255.255.0.0', 'max_hosts': 65534},
    'Class C': {'range': '192.0.0.0 - 223.255.255.255', 'default_subnet_mask': '255.255.255.0', 'max_hosts': 254}
}
total_classes = len(ip_classes)
# Create class_names list below
# Your code here

Need a hint?

Use the keys() method on ip_classes and convert it to a list.

4

Add descriptions to each class

Add a new key called description to each class dictionary inside ip_classes with these exact values:
'Class A': 'Supports very large networks with many hosts',
'Class B': 'Used for medium-sized networks',
'Class C': 'Designed for small networks with fewer hosts'.

Computer Networks

ip_classes = {
    'Class A': {'range': '1.0.0.0 - 126.255.255.255', 'default_subnet_mask': '255.0.0.0', 'max_hosts': 16777214},
    'Class B': {'range': '128.0.0.0 - 191.255.255.255', 'default_subnet_mask': '255.255.0.0', 'max_hosts': 65534},
    'Class C': {'range': '192.0.0.0 - 223.255.255.255', 'default_subnet_mask': '255.255.255.0', 'max_hosts': 254}
}
total_classes = len(ip_classes)
class_names = list(ip_classes.keys())
# Add description key to each class dictionary below
# Your code here

Need a hint?

Add the description key with the exact text to each class dictionary inside ip_classes.