ocr comp sci protocols and layers

TCP/IP

Transmission Control Protocol/Internet Protocol

• allow communication over WAN

• TCP is responsible for making sure there are no errors in communication between two routers by splitting data into small packets

• IP makes sure data is sent to the correct device on a WAN

HTTP

Hypertext Transfer Protocol

• defines how web browsers work

• allows communication between client and server for website viewing

• allows clients to receive data from server and send data to the server

HTTPS

Hypertext Transfer Protocol Secure

• defines how web browsers work

• allows communication between client and server for website viewing

• allows clients to receive data from server and send data to the server

• adds a layer of security so all data sent and received is encrypted

• used to protect sensitive information

FTP

File Transfer Protocol

• allows sending and receiving files between computers

• used to upload and download files to/from web servers

POP

Post Office Protocol

• downloading emails to a device from an email server

• removed from server after retrieved

IMAP

Internet Message Access Protocol

• reading emails from an email server

SMTP

Simple Mail Transfer Protocol

• allows communication between an email sender and email server

What is a protocol?

set of rules that govern communication on a network.

what is a layer?

• sub part of a more complex task

• dividing network tasks into layers reduces complexity and makes each layer more manageable

• TCP/IP uses 4 layer model (stack)

advantages of layers

• self contained so managing/repairing/upgrading is easier because each layer independent

• allows for focus on specific parts of a protocol

• promotes data exchange between hardware and software