Protocols Flashcards
What is a network protocol
It is an agreed way of how to communicate over a network
What is a protocol
it is an agreed set of rules of how to do something
What does TCP/IP stand for
Transmission Control Protocol / Internet Protocol
What is TCP/IP used for
This protocol prepares messages for transmission and reassembles any received messages
When sending data the TCP rules include…
- Dividing the message into packets
- Adding a sequence number to each packet so the message can be reassembled
- Adding extra error-correction information so errors can be spotted and fixed
When receiving data the TCP rules include
- Examining each packet for errors by using the extra information that was added to it
- Fixing any errors or requesting that the packet can be re-sent
- If all packets are present, using the sequence number of each packet to reassemble the message
When sending data the IP rules include…
- Add the destination address to each data packet
- Add it own address to indicate where it came from
When receiving data the IP rules include
- Accept data packets that its own address attached
- Ignore all data packets that do not contain its own address
What does HTTP and HTTPS stand for
HyperText Transfer Protocol and HyperText Transfer Protocol Secure
What is HTTP used for
This protocol allows a browser to request these individual files from a web server in a orderly way
What is HTTPS used for
This protocol works like HTTP but also encrypts web page data before it is sent out of the browser or server
What does FTP stand for
File Transfer Protocol
What is FTP used for
It is used to transfer files between a client and server on a computer network
What does POP stand for
Post Office Protocol
What is POP used for
Allows emails to be downloaded and/or deleted from a mail server and viewed offline by an email client
What are the disadvantages of POP
- It can only handle one mailbox
- Messages, once downloaded are removed from the server and cannot later be viewed by other devices
- It does not support complex searches of emails on the server
What does IMAP stand for
Internet Message Access Protocol
What is IMAP used for
It is similar to POP but it also offers more complex commands to manage emails on the server itself
IMAP allows you to…
- Set flags on emails showing where they have been viewed replied to etc.
- Access emails on multiple devices i.e PC, phone, tablet etc.
- It can handle more than one mail box
- You can choose where to download just the headers, full body or not to download attachments
What does SMTP stand for
Simple Mail Transfer Protocol
What is SMTP used for
It is used by the mail server itself to send and receive emails from all other mail servers across the internet
How does Ethernet work
It is a family of protocols responsible for sending and receiving data along a network cable
The Ethernet protocol is in several parts such as…
Hardware - Specifies the performance expected of network cables, plugs and sockets
Data format - Describes the format of the data packets sent or received over the network
-How to deal with data collisions
How does Bluetooth work
It is a wireless protocol that was developed to allow devices that are very close to exchange data
Name the four layer model
Layer 4 - Layer name -Application layer
Protocols - FTP, HTTP, POP, IMAP, SMTP
Purpose - The protocols in this layer provide access to email, files and websites across an IP network
Layer 3 - Layer Name - Transport Layer
Protocols - TCP
Purpose - It is responsible for dividing messages into packets, adding sequence numbers and error correction info
Layer 2 - Layer name - Internet Layer
Protocols - IP
Purpose - It is responsible for managing the address of source and destination locations
Layer 1 - Layer name- Network/Data link access
Protocols- Ethernet, Wi-Fi
Purpose - They are responsible for transmitting and receiving data through cable or wireless
What are the benefits of using a layer model
- It is useful for manufacturers so that they can ensure their hardware is compatible with existing protocols
- We can map how layers relate and interact with each other
- When a new protocol is developed, it can be slotted into the appropriate layer
