Networks - What are networks? Flashcards
What does LAN stand for?
Local Area Network
What are the attributes of a LAN?
Hardware is owned by corporation that uses it
Wired or wireless
Often found in businesses, schools and universities
Lots of homes have a LAN to connect to different devices
What is WAN?
A Wide Area Network that connects LANs
What are the attributes of WAN?
Connects LANs in different geographical locations (countries)
Very expensive
Connected using telephone lines, satellite links or radio links
Example of WAN is the internet
Why is WAN so expensive?
Organisations have to hire infrastructure from telecommunications companies who own and manage the WAN.
What is PAN?
A Personal Area Network that connects devices over a short range
What are the attributes of a PAN?
Centred around a single user (usually)
Often used to transmit between smartphone or wearable devices
Often use Bluetooth - strong but short range
Don’t require additional hardware - good
What does NIC stand for?
Network Interface Card
What does an NIC do?
It is a piece of hardware inside a device that allows it to connect to networks - wired and wireless
What are switches used for?
To connect devices on a LAN
How are routers used?
To transmit data between different networks
What factors affect the choice of cable needed in a wired network?
Cost
Bandwidth
How far you need to transmit data
What are the 3 types of cables?
Fibre optic
Cat 5e / Cat 6
Coaxial cables
What is bandwidth?
The amount of data that can be sent across a network in a given time
What do “Fibre Optic” cables do?
Transmit data as light
High performance
Expensive
Don’t suffer interference
Transmit over very large distances - at high bandwidth without loss of signal quality
What are Cat 5e / Cat 6 cables?
Common types of Ethernet
Contain pairs of copper wires twisted together to reduce internal interference
Cheaper than fibre optic cables
Decent bandwidth
Commonly used in homes and offices for a LAN
What are coaxial cables?
Made of single copper wire surrounding by plastic layer for insulation
A metallic mesh which provides shielding from outer interference
Very cheap
Low bandwidth
What are benefits of networking computers?
Sharing files is easier - users can access the same files…
Share the same hardware between multiple devices
Install and update software all at once (rather than 1 by 1)
Can communicate across a network cheaply and easily (e.g email)
Users can log in from any device on the network
What are the disadvantages of networking computers?
Expensive to set up - need lots of hardware
Vulnerable to hacking and malware - all the computers are connected
Some networks are dependent on servers - if they go down it is very disruptive
Large networks are difficult to manage and may need to employ a specialist to maintain them
