A2 ICT

A2 ICT

1. Networks

   • Factors of influence
     • Cost
     • Size of organisation
     • How system will be used
     • Existing systems
     • performance required
   • Security issues
     • Access to illicit material
       • use proxy
     • How payments can be protected
       • Use encryption
     • The need to restrict staff access to certain files
       • Implement user accounts
     • Blocking downloads of copyrighted material
       • Block downloads
   • Network acrhitecture
     • Client server
       • All data saved cenrally
       • Small programs distributed e.g. virus updated
       • Access levels centrally
       • Central backup
     • PEER TO PEER
       • All data distributed equally
       • Software stored on each machine
       • No central security
       • No central backup
   • Topologies
     • Star
       • Fault tolerant
       • Load tolerant
       • Very expensive
       • Dependent upon central server
     • Ring
       • No dependence on central server.
       • Cheaper to install, cable costs etc.
       • Faults hard to locate
       • Cannot keep network running when adding new equipment
     • Bus
       • Cheap
       • Easy to add new machines
       • Becomes slow if too many machines added
       • If faults develop, network fails.