Topic 14

Topic 14

1. Back Up

   • What data?
   • How often
   • When
   • Which media
   • Who's responsible
   • Where stored
   • Types of b-up
     • Incremental
       • Saves all of the files that have changed since the last incremental/full backup
       • Software decides which files to back up
       • fastest way to back up, but restore jobs can take a long time
     • Differential
       • Only data that is different since the last full backup is saved
       • Reduces time it takes to restore data- only uses the previous full and differential backups
       • If performed too much, can become larger than a full backup
       • data selected automatically by the backup software
       • slower than an incremental backup
     • Full
       • All data that is stored in your files and folders will be saved
       • Can be restored quickly if something goes wrong
       • Backup takes a long time
       • security issue as if the backup is lost/illegally accessed
   • Types of storage media
     • Magnetic Tape
       • High capacity, fairly inexpensive
       • finding particular files or folders is laborious
       • Fast to write/read data
       • faster than most hard disks
       • need special equipment
     • Optical Disc
       • Low capacity, Suitable for home or small business
       • Data accessed directly, lowers recovery times
       • Low cost
       • Most computers have rewritable CD drives, no extra equipment
     • Hard Disk
       • Mostly connected externally via USB
       • Low access times, high capacity, easy to use
       • Affordable
     • Remote backup service
       • needs high-speed Internet access
       • Reduction in risk that natural disasters, fire or terrorist attack can cause
       • All data is backed up off-site
       • Security risks

2. Recovery

   • hardware available
   • software available
   • data available
   • Staff available
   • communication links
   • alternative location
   • system secure
   • Continuity of service
     • ICT services in a business must not be disrupted for too long
       • lose income if their web site is not operational
       • Servers should be situated in the correct location
       • appropriate backup and security measures in place-
         • ensure the continuity of service is as reliable as poss
       • Expensive in short term, but security of network and data = priority
         • ensure they can trade without interruptions
       • 90% of businesses that lose data from a disaster are forced to close within 2 years of the disaster
         • 50% of companies experiencing a computer outage will be forced to shut within 5 years
     • disaster recovery planning ensures:
       • Resume trading quickly- ensure ICT services back online asap
       • customers, investors and trading partners have confidence in reliability of the company
       • Retain customers who might change companies if loss in trading time

3. Responsibilities of b-up and rec

   • If on a standalone computer, your responsibility to ensure data on it is adequately backed up
   • network manager responsible, based company’s backup and recovery procedures
   • good disaster recovery plan = essential, will minimise impact e.g. loss of data