security

Question 1

What is TCP

Answer 1

transfer control protocol - breaks up messages sent over the internet in to small chunks called packets

Question 2

what is each packet given

Answer 2

header
the IP it is going to 
the IP address it has come from 
the sequence number of the packet
the number of packets in the whole communication.

Question 3

HTTP

Answer 3

hypertext transfer protocol - governs communication across the internet

Question 4

HTTPS

Answer 4

hypertext transfer protocol secure- is a more secure version of HTTP, often used to handle financial transactions.

Question 5

FTP

Answer 5

file transfer protocol - governs the transfer of files across the internet

Question 6

SMTP

Answer 6

simple mail transfer protocol- handles email communication

Question 7

TCP/ IP

Answer 7

transfer control protocol / internet protoccol- handles communications on a network.

Question 8

VoIP

Answer 8

Voice over internet protocol - handles audio/visual communication

Question 9

SSL

Answer 9

secure socket layer-a protocol which allows secure links between computers

Question 10

TLS

Answer 10

transport layer security - a recent, more secure version of SSL.

Question 11

what is SSL used to secure

Answer 11

online credit crd transactions

any sensitive data exchanged online

Question 12

why do mobile phones need two MAC addresses

Answer 12

one for the wifi and one for the bluetooth.

Question 13

what is meant by data losing its value

Answer 13

the more accurate and complete the data is, the more valuable it is. if the data is lost, corrupted or accidentally changed, it becomes less accurate and complete and loses value.

Question 14

what is an automatic backup

Answer 14

is where a computer makes a backup without user intervention. is where the computer automatically creates a backup at a scheduled time and date.

Question 15

explain how anti-virus software may help to prevent DDos attacks

Answer 15

denial of service attacks occur when malware on a computer instructs the computer to send a high volume of requests to a server
antivirus software detects and removes malware from computers, removing the cause of the attack.

Question 16

explain why computer security is more effective when anti-virus software and firewalls are used

Answer 16

malware is software designed to disrupt or modify a computer system
it is usually accidentally downloaded from mail attachments , websites and USB sticks.
antivirus software detects and removes malware from a computer, helping to keep the computer safe

Question 17

describe how a proxy server can help keep data safe

Answer 17

a proxy server is a computer that sits between a network server and the internet
the proxy server directs traffic away from the main server by examining the traffic
if the traffic is authorised it is forwarded to the network server; if not , the traffic is kept away from the network server keeping it and the data on it safe.

Question 18

what is the difference between symmetric and asymmetric encryption?

Answer 18

encryption converts data into a form that cannot be understood by anybody other than an authorised user.
encryption works by using a key
symmetric encryption uses the same key to encrypt and decrypt data
asymmetric encryption uses two separate keys which work as a pair
the first key is used encrypt the data
the second key is used to decrypt the data

Question 19

describe what a protocol is and how it helps protect data

Answer 19

a protocol is a set of rules that governs communications between computers
some protocols such as secure socket layer use asymmetric encryption to create a source link between one computer and another
this means that data can be safely transmitted between computers as anyone without the encryption keys cannot read the data

Question 20

how proxy servers prevent servers

Answer 20

proxy servers prevent direct access to the server. this is done by directing traffic to an intermediary server. the proxy server sits between the main server and the internet.

Question 21

what is the purpose of the proxy server

Answer 21

to direct traffic away from the network server. when a request comes in from the internet, the proxy server examines the request. if the request is thought to be valid , the corresponding data is retrieved from the network server and transmitted to the requesting computer. As a result, any attacks hit only the proxy server, not the network server itself.

Question 22

why can proxy servers can be beneficial

Answer 22

> if the data on a proxy server is lost, corrupted or changed the original data is still safe and secure on the network server.
a proxy server may hold certain data , but not sensitive data. an external computer can only access the data on the proxy server
as a proxy server can handle requests and transfer data, the network is free to handle requests from the computer on its own network speeding up internal access times.
proxy server can hold copies of frequently visited webpages. this speeds up access to those pages from computers on the network as the pages do not have to be downloaded from the internet.
can be used to prevent users from accessing external websites.
an organisation that receives large amounts of requests can use proxy servers to help spread the load.

Question 23

what is a firewall

Answer 23

is a security technology that monitors incoming and outgoing traffic. it provides a protective barrier between the computer and other computers.

Question 24

firewalls work through rules. 2 rules for the firewalls

Answer 24

only certain programs can be allowed to send and retrieve traffic

access to certain websites or servers can be blocked.

Question 25

what are the two types of firewall?

Answer 25

software firewall: protect an individual computer

hardware firewall: protects a network

Question 26

what are the disadvantage of firewalls

Answer 26

firewalls are very effective but because the user can modify the rules , unauthorised traffic still may occur.

Question 27

what are the 3 main types of backups

Answer 27

magnetic media
optical media
cloud storage

Question 28

what are worms

Answer 28

programs that do not delete or corrupt files like a virus. instead they replicate themselves over and over, filling a computers storage. this can cause a computer to run slowly or stop running all together

Question 29

what is a trojan horse

Answer 29

program that pretends to be other programs. when, they run they acting like viruses deleting and corrupting files.

Question 30

what is spyware

Answer 30

programs that collect personal data, then send it back to the spyware authors

Question 31

what is a server

Answer 31

a computer which handles requests from other computers

Question 32

what is a request

Answer 32

a communication which asks for data to be transferred

Question 33

what is authentification

Answer 33

security which prevents access to a computer even if the user has physical access

Question 34

how does antivirus software work

Answer 34

uses a list of malware called virus definitions and how they work. the software scans the computer and looks for any malware that it can recognise. if it finds any malware, the antivirus attempts to remove or blocks its access to the computer

Question 35

what is a brute force attack

Answer 35

generating every possible number combination in a key length and trying to decrypt its message