NEED TO KNOW MOCKS Flashcards
1
Q
What are Analogue signals?
A
Pieces of continuously changing data
2
Q
Why do Analogue signals need to be converted into digital data?
A
So computers can read and store sound files
3
Q
What is Sampling?
A
The process of converting analogue to digital
4
Q
What factors affect size and quality of Sound files?
A
- Bit depth
- Sample rate
- Bit rate
5
Q
What is Bit depth?
A
Number of bits available for each sample
6
Q
What is Sample rate?
A
How many samples you take in a second
7
Q
What is lossless compression?
A
Makes the file temporarily smaller by removing data to store the file
8
Q
What is a network protocol?
A
A set of rules for how devices communicate and how data is transmitted across a network
9
Q
What is a communication protocol?
A
- Specify how communication between two devices must start and end
- How data must be organised
- What devices must do if it goes missing
10
Q
What are Mac addresses?
A
48 or 64 bit binary numbers
—> Binary numbers are converted into hex
11
Q
What does HTTP stand for?
A
Hyper text transfer protocol
12
Q
What is a HTTP used for?
A
Used by web browsers to access websites and communicate with web servers
13
Q
What does HTTPS stand for?
A
HTTP secure
14
Q
What is a HTTPS used for?
A
- A more secure version of HTTP
- Encrypts all info sent and received
15
Q
What does FTP stand for?
A
File transfer protocol
16
Q
What is a FTP used for?
A
Used to access and move files between devices on a computer
17
Q
What does POP3 stand for?
A
Post office protocol (version 3)
18
Q
What is a POP3 used for?
A
- Used to retrieve emails from a server
- The server holds email until you download it, it’ll then be deleted after
19
Q
What does IMAP stand for?
A
Internet message access protocol
20
Q
What is a IMAP used for?
A
- Used to retrieve emails from a server
- The server holds email until you delete it
—> WE only download a copy
21
Q
Who uses IMAP the most?
A
Web-based email clients
22
Q
What does SMTP stand for?
A
Simple mail transfer protocol
23
Q
What is a SMTP used for?
A
- Used to send emails
- Used to transfer emails between servers
24
Q
What is a layer?
A
A group of protocols which have similar functions
25
What are the **4 layers** called?
* Applications layer
* Transport layer
* Internet layer
* Link layer
26
What is an **Applications layer**?
A networking layer which encodes or decodes a message
--> In a form that is understood by the sender and the recipient
27
Which **protocols** operate in the **Applications layer**?
* HTTP/S
* SMTP
* IMAP
* FTP
28
What is an **Transport layer**?
A networking layer which determines how a message is transmitted over a network
29
Which **protocols** operate in the **transport layer**?
* TCP
* UDP
30
What is an **Internet layer**?
Addresses and packages data, ready for transmission.
---> Then routes the packets across the network
31
Which **protocols** operate in the **Internet layer**?
IP
32
What is a **Link layer**?
A networking layer which facilities the transmission of a message across a network
33
What operates in the **link layer**?
* NIC
* Operating system drivers
34
What are the **advantages** of **layers**?
* Breaks network communications into manageable pieces
* Self-contained
* Has standards
35
How is *breaking network communications into manageable pieces* an **advantage** in relation with **layers**?
Helps developers concentrate only on one area of the network without having to worry about the others
36
How does *layers being self contained* an **advantage**?
An individual layer can be changed without it affecting the other layers
37
How does *layers having standards* an **advantage**?
Forces companies to make compatible, universal hardware & software
---> Different brands will work with each other
38
What is a **DNS server**?
Stores a list of domain names and a list of corresponding IP addresses where the website is stored
39
What are the steps taken to display a **Webpage**?
* Domain name is typed into the address bar of a browser
* A query is sent to the local DNS server for the corresponding IP address of the domain name
* Local DNS server will check if it holds that IP address to that domain name
---> If it does it will pass the IP address to your browser
* The browser then connect to the IP address of the server and accesses the web site
40
What will happen if the *local DNS server* does not hold the IP address?
Then another query is passed to another DNS server @a higher level until
41
What is the **first stage** of the **FDE cycle**?
The memory address held in the program counter is copied into the MAR
42
What happens after the *memory address held in the program counter is copied into the MAR*?
address in the program counter is then incremented by one
43
What happens after the *address in the program counter is then incremented by one*?
The processor sends a signal along the address bus to the memory address held in the MAR.
44
What happens after the *processor sends a signal along the address bus to the memory address held in the MAR*?
The instruction/data held in that memory address is sent along the data bus to the MDR
45
What happens after the *instruction/data held in that memory address is sent along the data bus to the MDR*?
The instruction/data held in the MDR is copied into the CIR
46
What happens after the *instruction/data held in the MDR is copied into the CIR*?
* The instruction/data held in the CIR is decoded and then executed. * Results of processing are stored in the ACC
47
What happens after the *instruction/data held in the CIR is decoded and then executed*?
The cycle then returns to step one
48
What is **ASCII**?
* 7 bits
* 128 character set
49
What languages would use **ASCII**?
English
50
What is **Extended ASCII**?
* 8 bits
* 256 character set
51
What languages would use **Extended ASCII**?
French, Spanish
52
What is **Unicode**?
* 16 bits
* Over 65,000 characters
53
What languages would use **Unicode**?
Mandarin, Arabic
54
How is **bit rate** calculated?
bit depth x sample rate
55
What are some *lossy* formats?
* JPEG
* MP3
56
What are some *lossless* formats?
* PDF
* WAV
57
What are **routers** used for?
To send data signals across the internet
58
How do **routers** work?
Collects knowledge of available routes to transmit data
---> Then determine the most suitable route for sending data
59
What is a **WAP**?
Uses a radio transceiver to allow wireless connections to a network
60
How can **WAPs** extended the *range* of a **wireless network**?
WAP can either receive and transmit traffic to other WAPs
or
It can be connected via a cable to the main network
61
What factors affect **network performance**?
* Number of devices on the network
* Bandwidth of the transmission medium
* Type of network
* Network latency
62
What is **bandwidth**?
A measure of the amount of data that the medium can transfer over a given period of time
63
What is **network latency**?
A measure of how long it takes a message to travel from one device to another across a network
64
High latency
lots of delays
65
Low latency
Small amount of delays
66
What will the *latency* be like in a **hub based network** and why?
High latency - hubs broadcast all messages to all devices
67
What will the *latency* be like in a **switch based network** and why?
Low latency - transmit messages only to the intended recipient
68
Advantages of **cloud storage**?
* Ability to access files from any location or any device
--> so long as an internet connection exists
* Access can be granted to another user so they can remotely access your data
* Reduced need to make backups
- cloud storage services back up the data for you
69
Disadvantages of **cloud storage**?
* No guarantee that someone else is not accessing your data
* No guarantee that your data is being backed-up
* Access to data is only possible with an internet connection - no connection means no access to data
70
Advantages of **star network**?
* Each node is separately connected - if one fails it will not affect the rest of the network
* Higher performance - message only passed onto intended recipient
71
Disadvantages of **star network**?
If switch fails as no node can communicate - whole network fails
Expensive - requires plenty of cable
