Networks Flashcards
What is a network?
A collection of devices connected together
Advantages of Networks
Enables us to share resources such as hardware devices and software
Disadvantages of Networks
Expensive hardware, risk of viruses and hacking and specialist staff often required
LAN
Local Area Network
- Network of computers based on the same site
- Generally connected using cables
- All hardware owned and controlled by organisation using it
- Typically connected using UTP cable, fibre optic or wi-fi
WAN
Wide Area Network
- Network of computers over a large geographical area
- Generally connected using satellites
- Multiple LANs connected
IP Address
Unique for every device on the Internet
e.g. 192.168.0.12
- Can change upon reconnection to a network such as the Internet
MAC Address
All devices have a unique MAC address which never change (series of letters and numbers)
Difference between MAC and IP Addresses
MAC address tells who you are.
IP address tells where you are.
What is a Domain Name System?
Server which stores a list of domain names and their matching IP addresses where the website is stored
What happens when a domain name is typed as a URL?
1) Domain name is typed as a URL
2) A query is sent to the DNS server for the IP address
3) The DNS server looks for the IP address or asks other DNS servers
4) When the IP address is found, it is passed to your browser
Client
The computer that sends a request
Server
The computer that responds to a request
Peer
A computer that acts as both client and server
Client Server Model
The server authenticates the user and then gives the client access to the requested files - best suited to organisations with a large number of computers
Peer to Peer Model
No centralised servers - best suited for smaller organisations with fewer computers and users
Advantages of Client Server Model
- Easier to manage file security
- Easier to back up shared data
- Easier to install software updates to all computers
Disadvantages of Client Server Model
- Can be expensive to set up and maintain
- Requires IT specialists
- The server is a single point of failure
- Users will lose network access if the server fails
Advantages of Peer to Peer
- Easy to maintain
- Specialist staff not required
- No dependency on a single computer
- Cheaper to set up
- No expensive hardware
Disadvantages of Peer to Peer
- Network is less secure
- Users will need to manage their own backups
- Can be difficult to maintain a well ordered file store
