Protocols Flashcards
(16 cards)
What is a protocol
A set of rules for how devices communicate and how data is transmitted across a network
When do you use a MAC address
When u are communicating on the same network
When do you need an IP address
When you are communicating between different networks eg the internet
Why do we need Mac addresses
Every device needs a unique identifier so it can be found on a network
Why do we need an IP address
They are assigned before we enter the network
We need it to send data over a network
What is data sent by
Packets
What do packets contain
A header which holds the information of where to go, where it are from and the packet number
A payload which is the content eg an email or document
A checksum number which is a form of validation used to check that thee payload data hasn’t beeen corrupted
How is packet switching used to direct data
Each packet is given a packet number to know what order it is
Each router reads the packet header so it knows where to go
When the packets arrive they use their packet number to get in the right order
It checks to see if all packets have rparrived if not then it will wait a certain amount of time before sending a timeout message to the sending device
What is tcp and ip
Transmission Control Protocol is the set of rules on how a device connects on the network so it is in charge of splitting data into packets and reassembling them
Ip is the internet protocol and is responsible for packet switching
What does http mean and do
Hyper test transfer protocol
Used by web browsers to access websites and communicate with web servers
What is https and what does it do
Hyper text transfer protocol secure
More secure version of http as it encrypted all the information sent and received
What does ftp do and stand for
File transfer protocol
Used to access edit and move files between devices on a network
Pop3
Post office protocol version 3
Retrieve emails from a server
Holds the email until you download it
Imap
Internet message access protocol
Used to retrieve emails from a server and holds the email until deleted
Smtp
Simple mail transfer protocol
Used to send emails
Why are protocols divided into layers
It breaks down network communication into manageable bits
As layers are self contained it can be changed without other layers being affected
Forest companies to be compatible and universal as all layers have set rules
