1. 1.5 Wired and Wireless Networks
In this unit you will cover…

2. 3. Protocols and Layers LOs To define protocol
To explain the need for agreed protocols on computer networks
To identify some of the most common protocols and their purpose

3. Protocols What is a protocol?
We rely on protocols all the time even if we don’t realise it – shaking someone’s hand, understanding tone in someone’s voice etc are all social protocols that we follow
If it weren’t for those protocols we’d struggle to communicate

4. Protocols
It’s the same for computers; protocols ensure that one computer can talk to another
Definition:
A protocol is an agreed, standardised set of rules which define how communication should take place between computer systems

5. A Rant Shut up, Wesley For anyone that watches Star Trek…
Imagine, you’re hundreds of light-years from Earth, you encounter a species that have never been encountered before… let’s just go and video call them
Sorry, but no.
Shut up, Wesley
All electronic communication relies on a set of very specific rules and specifications that must be exactly the same on both ends. These are protocols.

6. A whole bag of protocols
There are different protocols for different types of communication
The one you’ll be most familiar with is HTTP (hyper-text transfer protocol) for transferring hyper-text (which you should know is just web- pages)
Complete the table of protocols – don’t copy and paste, it’s just a waste of time.

7. Task
Protocol
Stands for…
Used to…
TCP/IP
HTTP
HTTPS
FTP
POP
IMAP
SMTP

8. Layers
Like onions and Ogres, networks have layers.

9. Layers Protocols are sometimes referred to as “protocol stacks”
This is because:
Protocols can be very complex
It is better to define each stage of a protocol in it’s own “layer”
Each layer can then be tightly defined which makes it easier to implement in hardware or software
It also means part of a stack can be in hardware and part in software which can save money

10. TCP/IP -Layers
The job of the different layers in TCP/IP is to separate the different jobs that are performed on packets as they are split up, filled with data and sent onto the network.
The jobs are also split between different devices; some are handled by software on the computer, a switch, a router or just rely on the transmission media