Networks

What is a Network?

Network: Two or more computers that can communicate with one another
- Networking enables services to be shared e.g. Printers, internet connection, email services, machine admin, back-ups, network storage, scanners.

Advantages	Disadvantages
Enables users to work from different physical locations	Additional hardware required
Hardware can be shared between computers	Potential security risks - shared viruses etc.
Enables communication	Additional support costs
Create more resilient systems	Certain hardware failures could affect all the computers
Enables distributed processing	Performance limited by network traffic
Easier monitoring of all users
May enable access to web services
Centralised back-ups are possible
Easier to maintain multiple devices

Topologies:
- Bus: All nodes connected to a single cable with terminators at each end
  - Less cabling needed
  - Better for smaller networks
- Ring: Nodes connected to each other in a ring shape. Take it in turns to communitcate
  - Very cheap
- Star: Nodes all connect to a central hub or switch. Used in most home broadband
  - Easy to add further nodes