Layers and protocols 2025 RDU

Do Now:

1. What does HTTP stand for?

2. What's the difference between HTTP and HTTPS?

3. What happens when a message is sent from one person to another via Whatsapp?

​Think-Pair-Share

Networks
Protocols and TCP/IP Layers

​Mr Dukes

Lesson Objectives

• Define a network protocol is and state why it is important.

• Identify the four layers of the TCP/IP model.

• Describe what happens at each layer of the TCP/IP model.

• Match common protocols (e.g., HTTP, TCP, IP) to the correct layer.

​Protocol (noun)

​Protocol (noun)

​​The rules about what you must do and how you must behave in official or very formal situations.

​Protocol (noun)

​​The rules about what you must do and how you must behave in official or very formal situations.

​A set of rules that govern how data is transmitted between devices on a network.

Multiple Choice

Which of these is the correct definition of a protocol in Computer Science?

• A method for data encryption.
• A set of rules for communication between network devices.
• A type of software application.
• A hardware component for networking.

Why do we need protocols?

​Turn & Talk

​Student A: I think we need protocols for transmitting data because...

​Student B: I agree because.. / would like to build on that... / would like to challenge that because...

There are several Protocols you need to know

• Ethernet, Wi-Fi

• HTTP / HTTPS

• FTP

• SMTP

• IMAP

• POP

• TCP

• IP

FTP

File Transfer Protocol (FTP)

This is when a computer sends or retreives files from a remote server or computer.

E.g OneDrive, iCloud, etc..

Sends from client to server // sends from server to client

Multiple Choice

What does HTTP Stand for?

• Hyper Text Transfer Protocol

• Hyper Text Transmission Protocol

• High Text Transfer Protocol

• Hyper Tech Transfer Protocol

Fill in the Blanks

HTTPS Stands for Hyper Text Transfer Protocol Secure. This means that the connection is

to make it more difficult for data to be read by hackers.

Multiple Choice

What protocol would be used to upload a photograph to the internet?

• HTTP

• HTTPS

• FTP

• ASAP

• RSVP

Multiple Choice

Which of the following is most likely to use HTTPS.

• Banking Website

• School Website

• Local Tourist Information Site

• Gaming site where you don't login

Multiple Choice

Which email protocol will be used when sending an email?

• SMTP

• POP

• IMAP

• IPA

• FTP

Open Ended

What is the difference between POP and IMAP?

Fill in the Blanks

Identify the most appropriate protocol to be used:

A customer wants to securely log into her bank’s website to check her account balance

Fill in the Blanks

Identify the most appropriate protocol to be used:

A user wants to transfer a file directly from his computer to his friend’s computer.

TCP

Transmission Control Protocol (TCP)

This protocol is responsible for:

• Setting up communication between two hosts

• Breaking up messages sent over the Internet into small chunks called packets

• Reassembles the packets at the other end

• Detects errors

• Resends lost messages
  
  

IP

Internet Protocol (IP)

This is the set of rules that dictate how data should be delivered over the internet

• Addresses and packages data for transmissions.

• Routes packets across the network

Multiple Choice

When data is sent over the internet it is broken up into...

• Packets

• Blocks

• Binary

• Boxes

Multiple Choice

What does TCP stand for?

• Transfer Control Protocol

• Transmission Control Protocol

• Transfer Character Protocol

• Transmission Character Protocol

Independent practice


Teams > Activity 1: Protocols

Answers

TCP/IP Layer Model

This layer model has 4 layers where different protocols operate to pass data across a network.

The four layers are:

1. - Application

2. - Transport

3. - Internet

4. - Link

Why layers are used

• Divides the complex task of networking into smaller, simpler tasks that work with each other.

• A layer can be removed/changed etc. …without affecting any other layers

• Each layer has its own purpose so it does not need to consider what the other layers do …so it can be programming individually

• Different layers can interface with different hardware from different vendors

​Which protocols would be used in each layer?

​Which protocols would be used in each layer?

​HTTP, HTTPS, FTP, SMTP, IMAP, POP3

​Which protocols would be used in each layer?

TCP

​HTTP, HTTPS, FTP, SMTP, IMAP, POP3

​Which protocols would be used in each layer?

IP

​HTTP, HTTPS, FTP, SMTP, IMAP, POP3

TCP

​Which protocols would be used in each layer?

Wi-Fi, Ethernet

​HTTP, HTTPS, FTP, SMTP, IMAP, POP3

TCP

IP

Multiple Choice

What are the advantages of layering?

• Modularity, separation of concerns, and reusability.
• Reduced performance and efficiency
• Higher maintenance costs
• Limited flexibility and adaptability
• Increased complexity and confusion

Match

Match the layer with the typical protocols used

• Application

• Transport

• Internet

• Link

HTTP, HTTPS, SMTP

TCP

IP

Ethernet, Wi-Fi

• HTTP, HTTPS, SMTP

• TCP

• IP

• Ethernet, Wi-Fi

Open Ended

The TCP/IP model uses layers including the application layer and transport layer.

Explain why the TCP/IP model uses layers.

Teams > Activity 2

Today we have:

• Defined a network protocol is and state why it is important.

• Identified the four layers of the TCP/IP model.

• Described what happens at each layer of the TCP/IP model.

• Matched common protocols (e.g., HTTP, TCP, IP) to the correct layer.