1.1.5 - Alternative Installation Processes

Question 1

What are the 4 alternative installation processes?

Answer 1

• Direct Changeover
• Parallel Running
• Pilot Running
• Phased conversion

Question 2

Direct Changeover

Answer 2

Replace old system with new system

Adv: minimal time + effort, new system available immediately

Disadv: If the new system fails, there is no fall back

Question 3

Parallel Running

Answer 3

New system is running alongside old system. Data must be entered into both systems.

Adv: - if new system fails, old system runs a backup
- outputs from two systems can be compared to see if new one is running correctly

Disadv: - running two systems is costly (time asw)

Question 4

Pilot Running

Answer 4

The new system is piloted (tested) with a small subsection of the organisation. Once running correctly, implemented across whole organisation.

Adv: - all features are fully trialed
- if new system fails, only a small part of the organisation suffers
- staff who were part of the pilot crew can train other staff

Disadv: - for the subset of users in the pilot crew, there is no backup if system fails

Question 5

Phased conversion

Answer 5

The new system is introduced in phases as parts of the old system are gradually replaced with the new system.

Adv: allows ppl to get used to the new system; training of the staff can be done in stages

Disadv: if the new system fails, there is no fall back for that part of the system