Networks 2

Networks 2

1. Stand alone and networked computers

   • Stand alone
     • Less liable to get hacked
       • No comms with other computers
         • Need own printer,scanner,software etc
   • Networked computer
     • Needs extra protection, ie firewalls
       • Potential data sharing
         • Can share printers, scanners, software etc

2. EPOS systems

   • item purchased is Idnetified
     • data sent to main computer
       • looks through database to find item details
         • description and price displayed on screen
           • after all items are processed total bill is calculated
             • receipt is printed
               • customer pays with cash or card

3. Data capture

   • Barcodes = 13 digits in 4 sections
     • 2 digits for where the item was made
       • 5 digits for manufacturer
         • 5 digits identify the product
           • 1 check digit for verification
   • Advantaged of barcodes TO CUSTOMER
     • fewer pricing mistakes
       • faster service
         • given itemised recipet that they can check
     • Disadvantages
       • Price not found on the item so they must find the place that it lives or a self scan station
         • scratched or crumpled barcodes take longer and could cause queues
     • Advantages of barcodes TO SHOP
       • No price tags needed
         • automatic stock control
           • patterns can be analysed
             • fraud is minimised by switching price tags

4. Optical mark recognition

   • detect small marks on paper when scanned
   • Used in multiple choice exams and lottery tickets
   • Advantages
     • Fast method of filling in forms
       • fats method of reading forms
   • disadvantages
     • forms can be large and have too many options
       • May be filled in incorrectly and cannot be marked

5. Optical character recognition

   • reads text and can process it into a word document
     • Offers fast input of data
     • Poor accuracy (handwritten)

6. Machine readable tags

   • Some items have scanable tags
     • can be scanned by a machine and update the stock control automatically
       • Advantages
         • Automatic stock control update
           • tags provide a record of daily sales
       • Disadvantages
         • customers may damage tags
           • update at end of day so not always up to date

7. Portable data entry

   • PDET can be carried around and scan items
     • then connected to the computer and updates the stock control
       • can be wirelessly downloaded
         • gather data about eh amount of stock availble
           • log data about items sent away by vans
             • traffic wardens on setting tickets

8. Touch sensitive data entry

   • Input data by touch screen, patients register them selves using them
     • Low level ICT skills needed
       • Little possibility of damage or theft
     • Dirty/scratched can make them hard to use/difficult to read