Fundamentals of computer systems

Fundamentals of computer systems

1. Standards

   • Refer to conventions and rules
   • Open standards
     • Publicly advailiable
     • HTML
     • HTTP
   • Orginaly none
   • De facto standards
     • Common usage
     • Microsoft Word
     • QWERTY keyboard layout
     • Post script
   • De jure standards
     • By law
     • TCP/IP
     • ASCII
     • PDF
     • Unicode
   • Proprietary
     • Owned by organisation e.g. Apple

2. Reliability

   • Mistakes in computer systems can lead to
     • Down time
     • Expensive errors
     • Data loss
     • Compromised privacy
   • Data integrity. Compromised by
     • Human errors when data is entered
     • Software bugs
     • Viruses and other malware
   • Reducing risks to data
     • Backing up data regularly
     • Controlling access to data via security mechanims
   • Testing
     • Reliability improved
     • Never fully complete because
       • Software is so complex
       • Testing is expensive
       • Testing is time consuming

3. Data Protection Act

   • Legislation needed because
     • easy to copy data
     • easy to transmit data
     • easy to match data and make judgements about other people
   • Laws
     • Allow people to view data held about them
     • Correct information when requested
     • Not use data in any way that can cause damage or distress

4. E-watse

   • Often shipped to developing countries where there are few safeguards
   • When burned produces dangerous chemicals such as dioxins