TCP congestion control in Computer Networks - Mini Project: Build & Apply

Understanding TCP Congestion Control

📖 Scenario: You are learning how computers manage data flow on the internet to avoid slowing down or crashing networks. TCP congestion control is a key method that helps computers send data smoothly without overwhelming the network.

🎯 Goal: Build a simple step-by-step explanation of TCP congestion control phases using clear terms and examples. You will create a list of phases, set a threshold value, describe how the phases change based on network feedback, and finalize the explanation with a summary.

📋 What You'll Learn

Create a list of TCP congestion control phases with exact names

Define a threshold variable for congestion window size

Write a simple logic description of how the congestion window changes in each phase

Add a final summary statement about the importance of TCP congestion control

💡 Why This Matters

🌍 Real World

TCP congestion control is used by all internet-connected devices to send data efficiently without causing network slowdowns or crashes.

💼 Career

Understanding TCP congestion control is essential for network engineers, system administrators, and software developers working on internet applications.

1

Create the list of TCP congestion control phases

Create a list called tcp_phases with these exact string elements in order: 'Slow Start', 'Congestion Avoidance', 'Fast Retransmit', 'Fast Recovery'.

Computer Networks

# Create the list tcp_phases with the four phases
# Your code here

Need a hint?

Remember to use square brackets [] to create a list and include all four phases as strings.

2

Define the congestion window threshold

Create a variable called ssthresh and set it to the integer 16. This represents the slow start threshold for the congestion window size.

Computer Networks

tcp_phases = ['Slow Start', 'Congestion Avoidance', 'Fast Retransmit', 'Fast Recovery']
# Define the slow start threshold ssthresh
# Your code here

Need a hint?

Use a simple assignment statement to set ssthresh to 16.

3

Describe congestion window behavior in each phase

Create a dictionary called window_behavior where keys are the phase names from tcp_phases and values are short strings describing the congestion window change: for 'Slow Start' use 'exponentially increases', for 'Congestion Avoidance' use 'linearly increases', for 'Fast Retransmit' use 'detects loss quickly', and for 'Fast Recovery' use 'temporarily reduces window'.

Computer Networks

tcp_phases = ['Slow Start', 'Congestion Avoidance', 'Fast Retransmit', 'Fast Recovery']
ssthresh = 16
# Create the window_behavior dictionary describing each phase
# Your code here

Need a hint?

Use curly braces {} to create a dictionary and match each phase to its description exactly.

4

Add a summary statement about TCP congestion control

Create a string variable called summary with this exact text: 'TCP congestion control helps prevent network overload by adjusting data flow based on feedback.'

Computer Networks

tcp_phases = ['Slow Start', 'Congestion Avoidance', 'Fast Retransmit', 'Fast Recovery']
ssthresh = 16
window_behavior = {
    'Slow Start': 'exponentially increases',
    'Congestion Avoidance': 'linearly increases',
    'Fast Retransmit': 'detects loss quickly',
    'Fast Recovery': 'temporarily reduces window'
}
# Add the summary string
# Your code here

Need a hint?

Assign the exact sentence to the variable summary using quotes.