Prelim Work

Question 0

What is computer architecture and name some parts of it.

Answer 0

This is the make up of a computer system. This includes many computer features such as processors, memory, cache, data bus, address bus, control bus and other buses. You should know about the data bus and address bus, not the control bus, that’s not in the prelim.

Question 1

What’s a virtual machine/emulator?

Answer 1

A computer that exists in the real world has an operating system that manages the hardware and software of the computer system. A virtual machine is a computer that runs software to emulate the functions of a real world computer. A virtual machine can be used by organisations to run software applications that are not available for then operating system platforms for real computers.

Question 2

What is a data bus?

Answer 2

This bus is used to transfer data between main memory and the processor. It is a two way bus since data can be transferred from a memory location to the processor and vice versa.

Question 3

What is the address bus?

Answer 3

This is used to specify the address of the memory location that is to be read from or written to. This bus is a one-way bus, since the processor will use it to specify which memory location it is going to use; but the reverse does not apply.

Question 4

What is R.A.D?

Answer 4

RAD- The rapid application development methodology was developed in response to the need to deliver systems very fast. However the RAD approach is not appropriate to all projects. RAD reduces development time.

Question 5

Name 3/5 users that will need to be taken into account accessibility wise.

Answer 5

Physical disabilities that prevent the user from holding or controlling a mouse.

Physical disabilities that prevent the user from typing or from using a keyboard.

Users with poor vision.

Colour blind users.

Blind users.

Question 6

What is encryption?

Answer 6

Encryption is the conversion of data into a form that cannot be understood by unauthorised people.

Question 7

What is open source software?

Answer 7

This refers to code used within a program, if ‘open source’ this means that the code is free to see and access is allowed to public.

Question 8

What is propriety software?

Answer 8

This is the term for when source code is guarded and the general public is not allowed to see the code involved or access it in any way.

Question 9

What is distributed storage?

Answer 9

Cloud storage is storage made available by hosting companies from which you can purchase it from. Rather than saving your storage on a physical hard drive you can use storage available on the severs.

Question 10

What is a digital certificate?

Answer 10

This is an electronic passport that allows a person, computer or organisation to exchange information securely over the internet using the public key infrastructure.

Question 11

What is the regulation of investigatory powers act? What did it do?

Answer 11

This act governs the use of covert surveillance by public bodies. This includes bugs, video surveillance and interceptions of private communications. (Eg phone calls and emails).

Question 12

What is a “Lifetime carbon footprint”?

Answer 12

This is how much of a carbon footprint a device will leave in it’s lifetime.

Question 13

What did the computer misuse act of 1990 introduce?

Answer 13

Gaining access to data held on a computer without permission e.g.

Gaining access to data held on a computer with the intention to commit a criminal offence. E.g. Hacking into the banks computer and wanting to increase the amount in your account.

Altering data held on a computer without permission. E.g. Writing a virus to destroy someone else’s data.

Question 14

If a company refused to let police search their encrypted emails what law would they be breaking?

Answer 14

The regulation of investigatory powers act.

Question 15

What is a “Dry Run”?

Answer 15

This technique involves stepping through the program through the programs instructions and manually working out on paper how the program variables.

Question 16

Examples of variable types in pseudo code are: (4)

Answer 16

Integer

Real

Boolean

Character

Question 17

What are examples of structured types? (3) Begin with (A) (S) (B)

Answer 17

Array, String, Boolean.

Question 18

Examples of sub programs? (2)

Answer 18

Procedure, function.

Question 19

Name some examples of assignments in psuedocode: (1)

Answer 19

Set to

Question 20

Name some examples of conditions (3)

Answer 20

If

Then

(Else)

End if

Question 21

Examples of fixed repetition (3)

Answer 21

Repeat… Times

End repeat

Question 22

Example of iteration in psuedocode? (9)

Answer 22

For

From

To

Do

End for

For each

From

Do

End for each

Question 23

Input/output examples in psuedocode? (7)

Answer 23

Receive from

Send to

Open

Close

Create

Question 24

Examples of predefined functions? (1)

Answer 24

Id(parameters)

Question 25

Think of the code that would be used for Input validation in psuedocode.

Answer 25

REPEAT

Receive mark FROM KEYBOARD

If Mark 100 THEN

SEND [“Not possible. Try again!”] To Display

End If

Until Mark >= 0 AND Mark

Question 26

Think of some psuedocode for a linear search.

Answer 26

Set position TO 0

Receive Search Value FROM KEYBOARD

REPEAT

IF item (position) =search value

Send [search value] to DISPLAY

END IF

SET position to Position +1

UNTIL Position = No of items in list.

Question 27

Think of some psuedocode for Finding the maximum value in a list.

Answer 27

Set Position to 0

Set Max to item (position)

FOR position from 1 to no of items in a list -1 do

IF item (position) > Max THEN

Set max to item (position)

END IF

END FOR

SEND [“The maximum value is”, Max] TO DISPLAY.

Question 28

Think of some psuedocode for finding a minimum value in a list.

Answer 28

SET Position to 0

SET Min to Item (position)

FOR position FROM 1 to no of items in list -1 DO

IF item (position)

Question 29

Think of some psuedocode for detecting counting occurrences.

Answer 29

SET count to 0

RECEIVE SearchValue FROM KEYBOARD

FOR position FROM 0 TO No items in list -1 DO

If search value = Item(position) THEN

Set Count TO Count +1

END IF

END FOR

SEND [Count] TO DISPLAY

Question 30

Graphic compression method?

Answer 30

LZW- This looks for commonly repeated patterns of bits that are stored in a look up table. Each pattern is allocated an index number, so that the index number can be stored instead of pattern.

Clut- This is a facility that enables a subset of colours to be stored as q local palette.

Question 31

Different between Client side and Server Sid scripting?

Answer 31

Client side scripting languages is when the scripting language is executed on the client computers of a network.

Server side scripting languages are the class of scripting languages that are executed on the server computers of a network.

Question 32

What are web crawlers?

Answer 32

Crawlers are programmes that automatically “crawl” around the web searching for pages to include in search engine databases.

Question 33

What is a ‘Bot’?

Answer 33

This is software that performs an automated task over the Internet that would be time consuming, repetitive or impossible for a human.

Question 34

Types of denial of service attacks?

Answer 34

Bandwidth consumption: This attack degrades the performance of a server by sending it a large amount of data packets in a short period of time.

Resource starvation: An attack can consume other resources apart from bandwidth in order to bring down a server.

Question 35

What is symmetric encryption?

Answer 35

This is the more basic than Asymmetric encryption. It encrypts data by using a secret key and encryption algorithm.

Question 36

What is Asymmetric encryption?

Answer 36

Asymmetric encryption is more complex than regular encryption, as it uses a combination of public and a private key to encrypt data.