The ICT Lounge
Section 7.6:
Stage 4 - Implementing a System
After testing completed and any errors/problems have been fixed, you should have a fully-functional system.

At this stage, the system is ready to be implemented (installed) into the customer's business or place of work.

There are several options available as to how this can occur and we will discuss them all in this section.

Key Concepts of this section:
Understand what is meant by System Implementation.
Know the different methods in which new systems can be implemented into an organisation.
Be able to describe advantages and disadvantages of each method.

Stage 4 - Implementation
Key Words:
Implementation, Direct, Parallel, Pilot, Phased.
What is system implementation?

Implementation just means to 'install' the system ready for use.

Implementation takes place during the fourth
stage of the systems lifecycle.
Implementing a system means to 'install' it.
Staff need to be trained in using the new system.
Before the new system can be installed, there are a number of tasks that must be completed.

These are outlined in the table below:

Staff training
Staff have to be able to use the new system before it is fully installed.

This ensures that the new system can be used straight after it is installed but involves expensive and time-consuming training.

Transfer files from
existing system to
the new system
If the old system was paper-based, existing paper files will need to be scanned and then input into the new computer system.

If the old system was electronic-based, existing files will need to be either:
  • Typed into the new system's database manually
  • Downloaded into the new system.

Changing over to the new system
Once staff are fully trained in the use of the new system and all of the company's files have been transferred, it is time to changeover from the old system to the new one.

Changeover simply means to switch from the old system to the new system and this can happen in four different ways:
Each of the changeover methods have advantages and disadvantages and we will discuss them in detail below:

Direct Changeover
With direct changeover, the old system stops getting used one day and the new system starts being used the next.

The direct changeover method offers a quick but high-risk way of implementing a new system.
(click image to zoom)
The direct changeover method is the fastest way of switching from one system to another.
This changeover method is risky because if the new system fails, there is no fallback.
The changeover is very fast and that's where the name 'direct' comes from.

Advantages / Disadvantages of Direct Changeover:
The fastest way of changing from one system to another.
Staff have to be trained and fully ready to use the new system before it is installed.

This training can be hard to fit into their daily schedules.
The new system can be used immediately after installation.
All of the old system's data needs to be uploaded into the new system's database before it is installed.

Again, this can be time-consuming and difficult to plan.
Cheap method of changeover as you don't pay for two sets of staff.

(Only pay the staff who are using the new system)
The old system is completely removed so there is nothing to go back to if the new system fails.

can be lost permanently.

This can be disastrous and could force the company to shut down for long periods until the system is fixed.
Less chance of the new system being faulty as it will already have been fully tested and checked.

Parallel Running
With parallel running, the old system and the new system are run alongside each other for period of time.

The parallel running method offers a low-risk but expensive way of implementing a new system.
(click image to zoom)
In parallel running, both systems run side by side until the new system has been proven to work properly.
The parallel running method is very expensive compared to other methods.
Data would be input into both the old system and the new system,producing two sets of results.

For Example -
In a billing system, both the old system and the new system would produce an invoice.

When staff are sure they can use the new system and that it is functioning properly, the old system is switched off.

At this point, the new system will be used exclusively.

Advantages / Disadvantages of Parallel Running:
If the new system fails, the old system is still available.

This way, no data will be lost.
This changeover method is much more expensive.

This is because you have the running costs of two systems instead of one

(Extra staff to run both systems, electricity etc.)
Staff can be trained in the new system gradually as the changeover doesn't happen immediately.
Excellent way to test the new system using live data.

(You can compare the results produced by both systems- any difference would mean an error with the new system)

Pilot Running
Implementing a new system using the pilot running changeover method involves introducing the new system to one part of the company first and then rolling it out to other departments later.

This method allows the new system to be tested in one department before being installed in others.
(click image to zoom)

The system could be installed in the warehouse department first.
Once proven to work correctly in the warehouse, the system could be installed into sales and then the rest of the company.
Pilot running takes a long time to fully implement the new system.
This method is a good way to test that the system works properly without having to massively restructure the company.

The term 'pilot' can be defined as 'to experiment or test before introducing something more widely'.

For Example:
If a company had three departments - warehouse, payroll and sales, the new system could be installed in the warehouse branch first.

The old system would still be used in the payroll and sales departments.

If the new system was a success in the warehouse department, it would be installed into the other two branches later.

Advantages / Disadvantages of Pilot Running:
If the new system doesn't work correctly, it only affects one part of the company.
It takes longer to implement the new system across the whole company.

(This is because the changeover happens gradually from department to department)
The implementation is on a smaller scale and is easier to manage than direct changeover.
The department taking part in the pilot can lose data if the new system fails.

(This is because the new system has replaced the old system)
Staff can be trained gradually from department to department.

The staff that were involved with the pilot scheme can also help train other staff.
It is cheaper than parallel running because the pilot is only used in one part of the company.

Phased Implementation
This type of changeover is where the new system is implemented one part at a time, in phases.

The phased implementation method offers a medium-risk but lengthy method of switching to a new system.
(click image to zoom)
In this method, the new system is 'phased in' and the old system is 'phased out'.
System errors are easier to weed out because you are only testing one part of the system at a time.
When each part of the new system has been fully tested and is known to work correctly, the next part is phased in.

Eventually the old system will be fully replaced.

Sometimes replacing an old system in this fashion is known as 'phasing it out'.

Advantages / Disadvantages of Phased Implementation:
Staff can be trained gradually as they only need to train in the part of the system that is currently being phased in.
More expensive than direct changeover as you have to test each phase separately before moving onto the next.
It is easier to find system errors as you are dealing with only one part at a time.

(If the whole system is implemented at once, it is harder to pinpoint the error)
Because the system is installed in separate phases, it can take a long time to implement the whole system.
If one part of the new system fails, it is still possible to access the parts of the old system that are still in use.
Only suitable for systems that can be split into separate parts.

(Not all systems can be implemented this way)

Which method of implementation is the most suitable?
Key Words:
Quick, Data Loss, Afford.
The most suitable method of system implementation depends on the situation and the needs of the organisation.

The table below highlights some examples of when each implementation method would be the best choice:

Implementation method
Suitable situation to use each method
Direct changeover.
Best where you want a quick changeover.

You simply stop using the old system one day and start using the new one the next.
Parallel running.

Best for use in departments within organisation's where you cannot afford to lose any data.

The two systems are run side by side so if there are any problems with the new system, you have the old system to fall back on.

The organisation must be able to afford the high costs of this type of implementation.

Pilot running.
Best for organisation's that have large, important departments that must not lose any data.

With pilot running you can use the new system in smaller departments first where any data loss will not be as catastrophic. Once the system is proven to run flawlessly, it can be installed into the larger departments.
Phased implementation.
Best for organisation's that cannot afford to lose data and can afford the time and cost of a slow changeover.


Click the above task and answer the questions about the Implementation Stage.

Please add your questions/comments below:

Links to Theory Units:
Section 4: Networks and the Effects of using them
Section 6: ICT Applications
Section 8: Safety and Security
Section 9: Audience
Section 10: Communication
Links to Practical Units:
Section 11: File Management
Section 12: Images
Section 13: layout
Section 14: Styles
Section 15: Proofing
Section 16: Graphs and Charts
Section 17: Document Production
Section 18: Data Manipulation
Section 19: Presentations
Section 20: Data Analysis
Section 21: Website Authoring