Networks Flashcards
A network connects a number of digital devices. As well as these devices it requires:
-NIC/ network interface card
- Cabling or WAP/ wireless access point
- A router
- A hub or switch in some networks
- Standards and Protocols
NIC
Network interface card either installed or plugged into the computer. Most computers have them installed
How to connect a wired Vs wireless network
Wired: cabling
Wireless: WAP
Router purpose
Connect network to other networks like the internet
Hub Vs Switch
Hub is “dumb” and sends messages down every wire
A switch has a processor which it uses to direct messages down the correct wire
Standards
Protocols
Standards - shared methods
Protocols - standards for communication
How are internet standards/protocols enforced
No one enforced them but it makes sense to follow them if they want to be connected
LAN
Local area network- all computers on the same site , connections privately owned
WAN
Wide Area Network - a collection of LANS. That communicate with each other eg. The internet
Joins devices remotely using public infrastructure
Bus network type
One cable connects every node / device
All data is transmitted via said cable
- cheap
- slow
-insecure
-cable fail = total fail
Star network
Each device has it’s own cable. Seperately connected to a hub or switch which directs traffic
- fast , large
- greater privacy
- more robust
- expensive to set up
Wireless network
No wired connections , every device uses a wireless adapter.
WAP at the centre , around 20m .
Devices can be portable
Every device needs an adapter
Signals could be inercepted
Mesh network
Many routes through the network
No central hub
Most reliable form of network
Peer to peer
All computers are equal
Cheap, slow , smaller capabilities/capacity
Client server networks
Server stores files for other computers (clients)
More data can be used more work can be done faster
if server has a fault the network fails
Needs technicians
Expensive
Client side processing
Work done by the client
Server side processing
Work done by the server
Fat client pros and cons
- works even if network down
- less strain on server
- more capable computers needed
- need to buy more software
- less control of clients
Thin client pros and cons
- cheaper computers
- buy less software
- control over clients
- relies entirely on server
- created more traffic as constantly communicating w server
Print server
Connected to a shared printer and pass files through to it
Mail server
Sent messages from one client to another
Internet server
Store process and deliver requested info / web pages to users
Name 3 network threats
- hackers
-malware - social engineering
Virus
Creates copies of itself
Not a complete file, a short bit of code
Has an effect when copied into an executable file
When run the virus is executed and does harm
