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.

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

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

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

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.