computer networks, connections and protocols

Question 1

what is a LAN?

Answer 1

local area networks cover small geographical areas.

Question 2

what is a WAN?

Answer 2

wide area networks cover large geographical areas.

Question 3

what is bandwidth?

Answer 3

how much data can be sent and received over a network successfully in a given time.

Question 4

what is a client server network?

Answer 4

a type of network where all devices are connected to a central server. the server is responsible for distributing data to and from the clients. the central server is also responsible for managing the network.

Question 5

what is a peer to peer network?

Answer 5

a type of network where all the devices are responsible for being servers on the network. this means whenever data is requested from a server all devices are responsible for searching for and sending the requested data and devices manage the network.

Question 6

what is the wireless access point?

Answer 6

used to allow devices to connect to a network wirelessly without any need for cables.

Question 6

what is a router?

Answer 6

used to send data between multiple networks. you cannot connect to a WAN such as the internet without a router. a router uses an IP address to direct traffic between network.

Question 7

what is a switch?

Answer 7

used in a network to send data around a network. a switch however sends data only to the correct device on the network. this is because they can read the data packets being sent and therefore work out where the receiver is.

Question 7

what is a hub?

Answer 7

used in a network to send data around a network but sends to all the devices instead of just the correct device.

Question 8

what is a network interface card?

Answer 8

used to connect a device to a wired or wireless network and is built into the device. it uses protocols to ensure the connection between the device and network is consistent.

Question 9

what cables are there?

Answer 9

copper cable- copper cables twisted around each other , one is responsible for sending data and the other is for receiving data.

fibre optic- use light to transmit data, cover a larger range compared to copper and have a much higher bandwidth due to less interference.

Question 10

what is the domain name system?

Answer 10

contains IP addresses for the various web pages associated with a website. DNS are used to make it easier to remember URLs rather than IP addresses.

Question 11

what is an IP address?

Answer 11

unique to each device connected to the internet IP addresses are used to allow data to be directed around the internet from senders to the correct receivers.

Question 12

what is a MAC address?

Answer 12

addresses that are specific to a piece of hardware on a network. they are built into the hardware (NIC)and therefore cannot be changed.

Question 13

what is hosting?

Answer 13

when websites are stored on servers dedicated to acting as DNS. hosts often provide 24/7 access to the website , access for multiple users, and greater security, compared to hosting your own website.

Question 14

what is the cloud?

Answer 14

applications and data stored and accessed via the internet.

Question 15

what are virtual networks?

Answer 15

when the logical structure is applied to a network independent of the physical structure.

Question 16

what is star topology?

Answer 16

all devices connected to a central hub or switch.

Question 17

what is mesh topolgy?

Answer 17

all devices on the network are connected to as many other devices on the network as they can.

Question 18

what is encryption?

Answer 18

a security measure while sending data. data is scrambled into a secret code that no one can understand without the decryption key.

Question 19

what are protocols?

Answer 19

a rule or standard that devices must follow when communicating with each other over a network.

Question 20

what is TCP/IP?

Answer 20

Transmission Control Protocol/ internet protocol sets out the rules devices must follow when communicating with each other. it also plays an important role in packet switching.

Question 21

what is HTTP?

Answer 21

hyper text transfer protocol is used to transfer web pages from web servers to clients.

Question 22

what is FTP?

Answer 22

file transfer protocol is used to transfer large files over a network and organise files for websites on a web server.

Question 23

what is HTTPS?

Answer 23

hyper text transfer protocol secure is a more secure version of HTTP. data sent using this protocol is encrypted and is more secure.

Question 24

what is POP?

Answer 24

post office protocol is used to access emails from an email server for the client to read. the email is downloaded and therefore removed from the web server when accessed.

Question 25

what is IMAP?

Answer 25

internet message access protocol is also used to access emails from an email server for a client to read. however this protocol allows the user to access the email directly from the the email server therefore removing the need to download or remove it.

Question 26

what is SMTP?

Answer 26

simple mail transfer protocol sends emails to an email server.

Question 27

what is a data packet?

Answer 27

data is too large to be sent over a network in one go. therefore it is broken down. each data packet is given a header which contains important information like:
- senders IP address
- receivers IP address
- error check- whether it arrives correctly
- packet sequence- order to put it bak together
- data

Question 28

what is packet switching?

Answer 28

process of sending data packets over a network:
- request received from a client. TCP breaks down the data being requested into data packets.
- each packet is stamped with important info.
- packets sent to receiver via quickest route by IP. packets often split up here- it doesnt matter how they get there just so that it is quick.
- once received error check happens
-TCP checks to see if the transmission was successful
- if any are missing or damaged the TCP will request to be resent
- a timer is set, if it takes too long an error message is sent to the sender
- TCP then puts the packets back together