network protocols

Question 1

what is a network protocol?

Answer 1

A protocol is a set of rules for how devices communicate and how data is transmitted across a network.

Question 2

how is data sent in a protocol?

Answer 2

data sent between networks are split into equal-sized packets. Each packet contains extra information eg. the destination and source addresses and a checksum used to find errors.

Question 3

how are network protocols organised?

Answer 3

network protocols are divided into layers.

Question 4

what is a layer?

Answer 4

A layer is a group of protocols that have similar functions.

Question 5

how many layers are in the TCP/IP model?

Answer 5

there are four layers of

Question 6

what is layer 1 called and what is its function?

Answer 6

layer 1 is called the link layer.
it is used to pass data over to the physical network

Question 7

what protocols may be used in layer 1?

Answer 7

wi-fi and ethernet

Question 8

what is the name of layer 2 and its function?

Answer 8

layer 2 is called the internet layer
— it is used to add IP addresses to data packets, directing them between devices
—They are used by routers.

Question 9

what protocol may be used in layer 2?

Answer 9

IP

Question 10

what is layer 3 called and what is its function?(2)

Answer 10

layer 3 is called the transport layer
— it is used to set up communication between a sender and a receiver
— IT is also used for splitting data into smaller pieces

Question 11

what is layer 4 called and what’s its function? (1)

Answer 11

layer 4 is called the application layer
— it is used for providing networking services to applications — eg. turning data into websites.

Question 12

what protocols are used in layer 3?

Answer 12

TCP and UDP

Question 13

what protocols are used in layer 4?

Answer 13

HTTP, HTTPS, FTP, SMTP, IMAP

Question 14

what are the advantages of using layers?

Answer 14

it breaks network communication into manageable pieces. Which helps developers concentrate on only one area of the network without having to worry about the others.

Question 15

what is the advantage of layers being self-contained?

Answer 15

layers can be changed without affecting the other layers.

Question 16

advantage of layers having set rules

Answer 16

having set rules for each layer forces companies to make compatible, universal hardware and software, so different brands will work with each other and always work in basically the same way.

Question 17

what else is the application layer responsible for ?

Answer 17

files, emails and data transfer

Question 18

what does HTTP stand for and what is it used for?(2)

Answer 18

it stands for Hyper Text Transfer Protocol.

governs communication between a web server and a client (the web browser)

Question 19

what does HTTPS stand for and what is it used for?

Answer 19

stands for Hyper Text Transfer Protocol Secure. It is a more secure version of HTTP as it encrypts all information sent and received.

Question 20

what does FTP stand for and what is it used for? (2)

Answer 20

stands for File Transfer Protocol.
—Used to transfer files like documents, music, or data across a network or the internet

Question 21

what does IMAP stand for and what is it used for?(2)

Answer 21

Internet Messaging Access Protocol.
—It is used to retrieve emails from a server.

Question 22

what does SMTP stand for and what is it used for?

Answer 22

Simple Mail Transfer Protocol.
— It is used to send emails

Question 23

what else does the transport layer do?

Answer 23

controls the packaging and unpackaging of data

Question 24

what does TCP stand for and what is it used for?

Answer 24

Transmission Control Protocol.
Controls the packaging and unpacking of data using numbered data packages so that no data is lost.

Question 25

what does UDP stand for and what is it used for?

Answer 25

User Datagram Protocol. controls the packing and unpacking of data without numbering data packets so it is unreliable and data may be lost.

Question 26

what is UDP best used for?

Answer 26

Gaming and live video streaming as TCP would take too long to deliver the packets and it is much preferred to have speed rather than 100% reliability when gaming or streaming.

Question 27

what is TCP best used for?

Answer 27

downloading files as it is preferred to have a reliable connection. Missing data packets can cause files to be corrupted and unusable, but you wouldn’t want to have to redownload the whole file.

Question 28

what does IP stand for and what is it used for?

Answer 28

Internet protocol. to deliver data packets from one device to another. they use ip addresses to give a unique name to each packet which directs it to the correct router.

Question 29

what is Wi-Fi?

Answer 29

Wi-Fi is the standard set of protocols for wireless LANs — wi-fi is a family of protocols commonly used in WLANs — units sent on the link layer are called frames instead of packets

Question 30

what two radio frequency bands do wi-fi use?

Answer 30

2.4 GHz and 5 GHz

Question 31

what are the benefits of both frequencies?

Answer 31

2.4 GHz has a greater range and is better at getting through walls and other obstructions whereas 5 GHz is faster over short distances

Question 32

how are the radio frequency bands split up?

Answer 32

they are split in to channels that each cover a small frequency range.

Question 33

what happens when channels overlap

Answer 33

it can cause interference

Question 34

what is the ethernet used for

Answer 34

handling the transmission of data between devices on LANs, specifically for wired connections.