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4.06 - Networked I / O Analysis


At the beginning of each feasibility study undertaken by a Task Force much of the team’s resource is directed towards data collection.

A systematic approach to identify the data requirements of a project to ensure that a time phased plan can be developed. This plan should attempt to provide the data just-in-time and not waste resources in non-critical data collection.

The basis for data requirements planning is the activity chart which is primarily used as a monitoring tool for Task Force programme control. For example, the machine-shop redesign project shown below.

Machine shop redesign project monitoring activity chart

Machine shop redesign project monitoring activity chart

Step 1

Take each task defined on the activity chart and perform a first pass input output analysis (see 4.03). This should be brainstormed by the whole Task Force to obtain most benefits.

Technical Audit - Plant & Tools - First Pass I / O Analysis

Technical Audit - Plant & Tools - First Pass I / O Analysis

Step 2

Take the first pass I/O and add further detail. This can be carried out by an individual Task Force member and later validated by the team. Thoroughness is important since this step is the foundation for the final stage.

Technical Audit - Plant & Tools - Detailed I / O Analysis

Technical Audit - Plant & Tools - Detailed I / O Analysis

Step 3

This step can be tackled in parallel with Step 2 by taking the first pass I/O analysis and matching them to the Activity Chart. This builds the foundation for a detailed data requirements network. The major sub-headings start to indicate the inter-relationship between tasks and give a guide to how the project as a whole fits together.

Preliminary I / O Network

Preliminary I / O Network

Step 4

Take the detailed I / O diagrams and layer them on top of the basic network. Inputs for each task can then be tracked to their source, which may be raw data or an output from another task highlighting a dependency.

The activity chart is time phased, therefore data requirements can be given for a first needed data and listing in chronological order will provide a hit list in priority order.

It should be noted that some of the low priority data may not be readily available or only on a long lead time and its generation or request may need to be made at the early stages of the project.

The benefits of this approach for data collection are:-

  • A systematic approach
  • A time phased and prioritised plan is produced
  • Confidence that the data collected are:-
    • Necessary
    • Identified for a particular task
  • A plan of campaign for the whole project is visible
  • All stages are documented and visible


Skilled use of the SADT/IDEF0 technique can make this process a lot quicker and more thorough than using simple I / O diagramming. Some of the IDEF0 diagramming software tools allow a timeline and enable the creation of a dependency chart whilst drawing the flow charts. Others enable Activity Based Costing (ABC) within the software also.

Further Reading