Network - 1.4

Network - 1.4

1. What a network is

   • A mass collection/grouping of computers - servers - mainframes - network devices - peripherals and other devices that are interconnected and connected to one another to allow the sharing of data
   • A group of computers that are interconnected

2. Main types of networks

   • Local Area Network (LAN)
     • What is LAN?
       • LAN is something that only covers small areas such as buildings or schools
   • Wide Area Network (WAN)
     • What is WAN?
       • WAN is usually made up of multiple LANs that have been put together, this is not always the case though but most of the time is what happens
       • Covers a large geographical area
         • For example the internet

3. Advantages of using a network

   • Device sharing saves money
     • Things such as printers
   • Files are easily shared on networks and is much harder when not using a network
   • Data is much easier to backup as all the data is stored on the file server.
   • They have good security
     • Users cannot see other users' files unlike on stand-alone machines this makes it more private and therefore allowing more private files to be allocated on networks
   • Client-Server Network
     • Server manages access to the internet.
     • Manages print jobs
     • Firewalls easily installed which is useful for lots of computers
     • All data is backed up in one go
     • It controls the security - additional hardware is needed
     • EXPENSIVE
   • Peer-To-Peer
     • Does not use a server
     • Backups are managed by their own computer
     • All computers have an equal status
     • Each device can act as its own client and a server
     • CHEAP
     • All devices can request and provide network services
     • Needs individual security

4. Disadvantages Of Networks

   • The purchase of network cabelling can be expensive
   • Viruses are easily spread to all computers while using a network, by using LAN you can not pass virus from computer to computer but on a network all computers are infected
   • There is a major danger of hacking - especially when WAN is being used and the security is low
     • To prevent hacks security measures are needed to be put in place which costs money
       • For example a firewall

5. Factors that affect performance

   • Number of Users - Too many users can slow down