Dangers of Computer Systems
Processes to protect data
Backup procedures and hardware
Types of backup routines:
- A generation file backup system
- This involves storage of three of the most recent versions of master file. (grandfather – father -son)
- Useful if one version is corrupted: the previous version(s) is still available.
- Data should be stored off site in case of a disaster.
Recovery routines:
- Buying new hardware
- Recovery after disaster – restoring databases/files
General backup procedures
- Test if backups work/can be restored
- Frequency of backup
- Timing, e.g. overnight
- Staff member with responsibility for ensures suitable back-up
External hard disc drive
- Speed of access – Very fast transfer which is important as daily updates
- Cost per unit of storage – external hard disc is quite cheap per byte of storage
- Portability reason – external hard disc is physically quite small and can be easily stored securely and safely for example in a fire proof safe
- Suitability: Not suitable unless justified
Cloud storage / upload to a third party storage provider
- Speed of access – very fast transfer achievable (depending on network speed) for daily updates
- Cost per unit of storage – could be cheaper or more expensive than external disk – accept either with justification
- Data is stored securely and safely on protected servers (or should be!)
- Suitability: Suitable for a large company if justified (i.e. contract in place for location of storage etc)
Flash memory stick
- Speed of access – Very fast transfer which is important as daily updates
- Cost per unit of storage – pen drive is quite cheap
- Portability reason – pen drive is physically small and can be easily stored securely and safely for example in a fire proof safe
- Suitability: Not Suitable for a large company
Magnetic tape
- Speed of access reason – Access to tape is serial and can be slow but could only back up files amended that day
- Cost per unit of storage reason – Tape is relatively (but drive can be expensive!) cheap compared with other secondary storage mediums
- Portability reason – Tape is physically small and can be easily stored securely and safely for example in a fire proof safe.
- Suitability: Used widely by large companies historically
Third Party Storage
Benefits of PC hard disc drive and external hard disc drive:
- Very fast access to files regardless of internet connection speed – not just ‘fast’ alone
- No one has access to ‘private’ files
- Cost of external hard disc drive. (Must be justified)
- No internet connection required
Drawbacks of PC hard disc drive and external hard disc drive:
- Backed up data is NOT protected from natural disaster or theft as in same location as PC hard drive
Benefits a third party storage provider:
- Data can be accessed by any device such as desk top PC or mobile tablet
- Data is not taking up storage space on physical device
- Data can be accessed anywhere in the world
- Fast transfer achievable (depending on network speed) for daily uploads
- Cost - Can be cheap (or free for limited storage space)
- Data is backed up by third party provider
- Data is stored securely and safely on protected servers (or should be! with encryption, passwords and firewall etc…)
- Allows collaborative working/file sharing
- Unlimited storage space could be available at a price
Drawbacks of a third party storage provider:
- No internet connection then no access
- Files could be compromised by hacker or employee
- Slow internet connection and upload and download will be frustrating
- Maximum file upload size may be limited
- Limited storage space unless uses pays a premium
- Cloud servers down (service unavailable) then files cannot be accessed