Topic B - Transmitting Data Flashcards
What are 6 wired methods of connecting devices?
USB SATA VGA HDMI Ethernet Cable Fibre Optic
Why is USB used?
Use it to connect peripheral devices of all kinds to our computer.
What are 4 advantages of USB?
Excellent data transfer speed.
Able to connect multiple peripherals to a single USB port.
Provides power to device while connected.
Highly compatible as every computer system has a USB port.
What is a disadvantage of USB?
Relatively short range
What is SATA?
Methods of connecting storage devices to a computer.
What are 2 advantages to SATA?
Extremely fast connection type.
All internal storage devices will have a SATA connector.
What are 2 disadvantages of SATA?
A SATA cable has a shorter range.
Doesn’t supply power to a device.
What does USB stand for?
Universal Serial Bus
What does SATA stand for?
Serial ATA
What does VGA stand for?
Visual Graphics Array
What is VGA used for?
A connector used for display devices such as monitors and projectors.
What are 2 advantages of VGA?
Highly compatible with older technologies.
Has locking mechanisms (cable stays secure).
What are 3 disadvantages of VGA?
Transmit analogue data (signal degrades).
Can’t handle the same quality resolution as other digital methods.
Can’t transfer an audio signal and video signal at the same (needs to separate cables).
What is HDMI?
Methods of connecting display devices
What are 2 advantages of HDMI?
Extremely high bandwidth (18 Gbps) (outputs very high quality display).
Audio signal can be transmitted along with video signal.
What is a disadvantage of HDMI?
No locking mechanism (cables can fall out of device)
What is an ethernet cable?
A form of UTP/STP cable that is used to transmit data between IT systems.
What are 3 advantages of an ethernet cable?
Very reliable connection method.
Very good range compared to other cables.
Most computers have an ethernet cable port.
Where are ethernet cables used?
In local area networks.
What is 3 disadvantages of an ethernet cable?
Limited mobility (needs physical wire). Rarely find an ethernet pot in mobile devices and becoming less common in laptops. Can't transfer data over long distances (not useful for large networks).
What is fibre optic?
A connection method where data is transferred through the use of pulses of light.
Where is fibre optic used?
In telephone lines.
What is 3 advantages of fibre optic?
Good transfer speed. (100 Gbps).
Excellent range (transfers data over 100km).
Very secure connection method.
What is a disadvantage of fibre optic?
It is very expensive (equipment to tune the network makes it costly).
What is infrared?
A technology that transmits data through infrared light.
What are 4 wireless methods of connecting devices?
Infrared
Bluetooth
WiFi
Mobile Broadband
Where is infrared used?
Remote controls
What is an advantage of infrared?
Low susceptibility to interference (connects devices to one to one).
What are 3 disadvantages of infrared?
Can only transmit data over very short distances (max 5m).
Requires line of sight (hard if obstacles are in the way).
Data transmission speed is very slow (max 4 Mbps).
What is bluetooth?
uses microwaves to transmit data.
What is an example of bluetooth?
For connecting peripheral devices, such as mice and keyboards, to your computer without any cables.
What is 3 advantages of bluetooth?
Easy to connect devices with.
Low susceptibility to interference.
Low power consumption (uses low power signal).
What is 2 disadvantages of bluetooth?
Relatively slow data transfer speed (max 25 Mbps). Poor security (automatic connections allows others to transfer data your device).
Why do we use WiFi?
To connect to a wireless access point in order to gain access to the internet as well as to connect wirelessly to a local area network.
What is WiFi?
Transmits data between computer systems.
What are 3 advantages of WiFi?
Fast data transfer speeds (max 2.5 Gbps).
Relatively large range (70 m).
Low cost installation.
What are 2 disadvantages of WiFi?
Complexed to set up (requires you to correctly configure a wireless access point).
If poorly configured, such as not setting a complex WiFi key, then it can be very vulnerable to hackers.
What is mobile broadband?
3G/4G internet we access wirelessly through a cellular connection.
Where is mobile broadband used?
Used to access the internet while on the go, such as while commuting to work, via a mobile device.
What is 2 advantages of mobile broadband?
Internet access is available almost everywhere.
Easy method to connect to internet (Requires no additional setup or configuration in order to access it).
What is 2 disadvantages of mobile broadband?
Very expensive compared to other methods (£20 plus for just 4GB for a month).
Slower data transfer speeds. (4G = 12 Mbps).
What is a network?
A network is where two or more computers are linked together in order to transmit data.
What 4 types of networks are there?
Personal Area Network
Local Area Network
Wide Area Network
Virtual Private Network
What is a PAN?
Allows us to connect our digital devices together, such as our personal computer and mobile devices.
Why is PAN used?
Used to connect devices within the range of a single person.
What is 3 advantages of PAN?
Reduces the needs for cabling, less trip hazards.
Automatic sync of data between devices, prevent mistakes.
Only connect over a small area makes the secure for transmitting data.
What is a Local Area Network?
A network that spans a relatively small geographical area, usually a single building or site.
What does LAN allow us to do?
Allow us to connect all of the computers in our home/business together to share data.
What are 3 advantages of LAN?
Peripherals can be shared within a business between multiple computers (Saves money).
Files can be stored in a central location (users can access from anywhere connected to the LAN).
Computers can be centrally managed (more efficient) backing up computers.
What is a Wide Area Network?
A network that spans a large geographical area, such as an entire country or the whole world.
What are 3 advantages of a WAN?
Confidential data can be shared between different offices (high security level).
Files can be accessed from different business locations.
Uses private leased lines rather than broadband internet connections to transmit data (faster data transfer).
What is Virtual Private Network?
A private network that runs across a public network.
How does VPN work?
By encrypting the data that is being transmitted over the internet.
Why is VPN used?
Used by businesses in order to allow employees to access their work network securely.
What is 3 advantages of VPN?
People gain secure access to their works LAN wherever.
Much cheaper than a WAN.
If used on public or unsecured network, the data transmitted is still secure as it is encrypted (unreadable to anyone who intercepts it).
What are the 10 factors affecting the choice of a network?
User experience User needs Specification Connectivity Cost Efficiency Compatibility Implementation Productivity Security
What 4 different types of data transmissions?
Email
Voice and video calls over the internet
Web pages
Secure payment systems
What 3 protocols come under email data transmissions?
SMTP
POP3
IMAP
What is SMTP?
Transmits data from your email client to your outgoing mail server.
Transmit data between email servers (move from your outgoing mail server to the recipient mail server).
What does SMTP stand for?
Simple Mail Transfer Protocol
What does POP3 stand for?
Post Office Protocol 3rd Version
What is POP3?
Used to download emails from your mail server to your email client.
What is the disadvantages of POP3?
You won’t be able to access your emails on multiple devices.
What does IMAP stand for?
Internet Message Access Protocol.
What is the difference between IMAP and POP3?
Instead of downloading emails, they are synced between your client and your server.
What is a benefit of IMAP over POP3?
You will be able to access the same emails on multiple devices.
What 3 protocols are there Voice and Video Calls over the internet data transmissions?
SIP
RTP
RTCP
What does SIP stand for?
Session Initiation Protocol
How does SIP work?
SIP signalling packet is sent from the person to the recipient.
SIP packet is received, recipients VoIP phone starts to ring.
What does RTP stand for?
Real time Transport Protocol
What does RTP do?
Transmits the data packets along the connection (works with SIP).
What is disadvantage of RTP?
Gives no guarantee for delivery.
Taking no responsibility for recovering lost packets.
What does RTCP stand for?
RTP Control Protocol
What does RTCP do?
Sends control packets that provide feedback on the quality of the data delivery.
What 3 protocols come under web pages data transmissions?
HTTP
HTTPS
FTP
What does HTTP stand for?
Hypertext Transfer Protocol.
What does HTTP do?
Establishes a connection between the client and server and then transfers web pages to the client.
What does HTTPS stand for?
HyperText Transfer Protocol Secure
What is HTTPS?
A version of HTTP that transmits data in a secure encrypted format using either TLS or SSL technologies.
What does FTP stand for?
File Transfer Protocol
What is FTP?
The protocol used when transferring files between computers over the internet.
When is FTP used?
When uploading web pages to a web server so they can be accessed by users browsing the web.
What is the first connection that FTP can establish (client to computer)?
Control connection
Once the control connection is established what is the second connection established?
Data connection
What is the control connection used?
To administrate the connections and to send commands.
What is the data connection used?
To transfer files between the client and the server.
What is the 2 protocols used for secure payment systems data transmissions?
SET
3D Secure
What is SET stand for?
Secure Electronic Transaction
What is SET?
A communication protocol that was initially supported by MasterCard and VISA for secure payments.
With 3D secure, what two pieces of information is sent to the retailers bank to complete the transaction?
Card details
Bank authentication
What is 3D secure?
Uses SSL encryption to ensure data is secure.
What are 2 security issues associated with transmitting data over a network?
Sniffing
Spoofing
What are packet sniffers?
Legitimate programs used commonly by network technicians to diagnose problems with a network.
What does a packet sniffer do?
Instructs your computer to inspect all data being transmitted over a network.
How can packets sniffers to be used maliciously?
Might be used to gain password or credits cards numbers that have been transmitted over the network.
What connections are vulnerable to packet sniffers?
Public WiFi connections
What connections aren’t vulnerable to packet sniffers?
Mobile broadband connections (4G)
What is spoofing?
Where you get your computer to pretend to be another computer.
How can an attacker spoof the network?
By using fake credentials and presenting them to the network they can fool the system into giving access to services meant for another device.
What can attacker do if they get into the network?
Will be able to access private and confidential data or even alter or delete that data.
How can spoofing be used to pefrorm a Denial of Service Attack? (DDOS)?
They can then send masses of data to overload the network making it unusable to the business.
What are 2 security prevention methods?
Firewalls
Encryption
What does firewalls do?
help prevent unauthorised access to data by monitoring traffic and blocking anything suspicious.
Where do hardware firewalls sit?
Sits between your local area network and the internet.
What does a hardware firewall do?
Monitors the traffic coming into the network from outside and will use defined rules to filter the traffic to prevent anything unwanted.
Where are software firewalls?
Installed on the individual devices connected to the network.
What does a software firewall do?
An monitor traffic going both into and out of the computer, filtering any unwanted traffic.
What does encryption do?
Data is converted into an encoded form so as to prevent unauthorised access.
What are 2 methods of encrypting data across a network securely?
SSL
TLS
What will SSL do?
Will encrypt the data to secure it so that it cannot be accessed by anyone who doesn’t have the encryption key.
What does SSL rely on?
SSL certificates or digital certificates
What does SSL certificates or digital certificates do?
Authenticate a user to the use the public key infrastructure to encrypt data transfer.
What is the bandwidth of a network?
The amount of data that can be transferred from one computer to another in a given period of time.
What is the latency of a network?
A measure of the time it takes for a data packet to transfer over a network.
What bandwidth/latency does online gaming need?
Low latency due to quick reponse time needed.
Large bandwidth isn’t needed.
What bandwith/latency does online streaming need?
Large bandwidth due to the amount of data that is transferred.
Low latency isn’t needed.
What is compression used for?
Reduce the size of files
What 2 types of compression are there?
Lossy
Loseless
Where is lossy used?
Video
Audio
Image compression
What is lossy compression?
Permanently deletes certain bits of data to reduce file size.
What is lossless compression?
Uses algorithms to pack the data into less space.
Where is loseless compression used?
Document compression
Where are Hardware CODECS used for?
Used to encode analogue data into digital data. It will then decode the digital data into an analogue form.
What are software CODECs used for?
Used with audio and video to compress the data so that it used transmitted over a network.
What is disadvantage to CODECs?
Can be compatibility issues to due to the variety of CODECs available.
What is an advantage of lossy?
File sizes are reduced much more than lossless compression (quicker upload/download times).
What are 3 disadvantages of lossy?
Reduced quality, cannot be restored to original high quality.
Person receiving file may not have same CODEC installed.
Sometimes file cannot be compressed further and so file can increase the file size.
What is an advantage of lossless?
Files can be decompressed back to original quality.
What is 3 disadvantages of lossless?
Can be seen as malware by anti virus software and block files meaning recipients cannot access the files.
Decompressing files can take a long processing time and memory (computer slows down).
Sometimes files cannot be compressed further and so file can increase the file size.
