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Flashcards in Paper 1 Deck (720)
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1

Bitwise XORing...

toggles a subset of the bits in the value

when you use a 1 the bianry is toggled/ switched around and 0s there is no impact

2

Depth First algorithm

1. PUSH the first node onto the stack
2. Repeat:
a. push each node onto the stack until a child node is reached
b. visit the node which is the lowest you can reach
c. if no node to visit pop off the stack
3. Until stack is empty

3

Encryption

Encryption is the process of encoding a message so that it can be read only by the sender and the intended recipient.

4

serialisation

Serialisation ensures that transactions do not overlap in time and therefore cannot interfere with each other or lead to updates being lost

5

Class

a template to set out a define what attributes an object of a certain type should have

6

how is redundancy used usefully

organisations build in redundancy e.g. duplicate hardware so that if the main system fails the backup can take over

7

X∧X=

X

8

do until loop pseudocode

do
code
until
condition

9

Sequence

do one statement after another in the correct order

10

Symmetric Encryption

Symmetric Encryption is when the same key is used to encrypt and decrypt the message. Both party’s must know the key and also keep it secret.

11

NOT

reverses the outcome of the expression

12

Byte Scale

bit, nibble, byte, kilobyte, mega, giga, tera, peta, exa, zetta, yotta

Multiple by 1024 to move up

13

Method of capturing data (Manual)

Paper data capture form (read by OCR & OMR or typed in manually)

14

purpose of operating systems: managing external devices

Using device drivers to translate operating system instructions into those understood by specific models of hardware device

15

How are character sets used to represent text?

When character in the set has a corresponding binary value which is a set number of bits. These are stored in a sequence that represents a word etc.

16

Capacity of magnetic

640 GB - 1TB

17

clock use

synchronise the change of state of flip flop circuits

18

linked lists

A list of data together with a set of links to sort the data. Data is stored in the order its input and pointers are used to link the data into the desired order.

19

Selection

do a set of statements based on conditions allow your code to make choices- otherwise known as branching

20

Peer-to-Peer Networking

No central computer, all computers are connected to each other locally or over a WAN

21

disadvantages of Client-Server

-Can be expensive to set up and to manage
-Server is single point of failure

22

how to convert floating point binary to denary

1) First work out the denary number in the exponent which tells us that the binary point moves 'n' places to the right
2) Write out a new binary weighting line with the point in the right place and then convert into denary

23

components of a packet

senders address, recievers address, packet contents, sequence number

24

Consistency

Any change in the database must retain the overall state of the database.

25

clock

sequential circuit that changes state at regular time intervals

26

Program Counter

stores the address of the next instruction

27

POST acronym

Power of self test

28

X∧0=

0

29

relationships

one-to-one
one-to-many
many-to-many

30

in two's complement the sign is stored in

the most significant bit