The Network Diagram - bringing order to project work flows.
Creating a network diagram, also referred to as a logic diagram, is a great way for starting to understand and visualise how your project will proceed. It's a simple concept successfully used in applications outside of project management planning; commonly used in manufacturing industries, as well as service industries requiring to map and understand work flows.
In the context of project planning, a network diagram is a sequence of steps (activities), commonly represented by blocks, that are linked together in the logical sequence they need to be carried out.
Producing a network diagram follows the completion of your project
Work Breakdown Structure. The pile of post-its that you have saved from the WBS exercise gets put to good use in developing a network diagram.
Once the logic diagram has been completed, you have a clearer picture of the required sequence of events and activities for your project.
You are able to clearly see the logic rules affecting activities, for example you cannot start building your house foundations until you have first prepared the ground.
By including the project team in the development of the network diagram, you obtain a consensus of understanding of how the project should be implemented, at the same time providing a forum for challenging accepted ways of doing things, which may need amending to suit the specific constraints associated with the project at hand.
An Example
The following is a very simple example of a network diagram. It's for one of life's important projects - making a cup of tea!
A couple things to notice, which will be found in your project network diagrams:
- Parallel work flows - see the activities which can be started at the same time at the beginning of the tea-making project? Sorting out the kettle and boiling water, getting the cups and saucers as well as collecting the milk and sugar. None of these activities rely on each other at the beginning.
- Logical sequence - see how the activities in the top sequence associated with making the tea, all fit together in a logical sequence. The tea cannot be infused (or brewed, if you are terribly English) until the tea leaves and then the boiling water have been added.
Simple! Though some tea-making purists may challenge the exact sequence.All the logic links in this simple example are referred to as Finish/Startlogic links. The succeeding activity cannot start until the preceding activity has finished.You can think of other types of logic links I'm sure. The following are a few examples:
- Start/Start - when one activity starts, another independent activity must start.
- Finish/Finish - two activities must finish at the same time.
- Finish/Start with a lag - the succeeding activity must start some defined time after the preceding activity has finished.
- Start/Start with a lag - when one activity starts, another must also start after a defined time.
You should be able to complete the remainder of the list now...TIP: Try and stick to Finish/Start logic only, when developing a network diagram. This forces a deeper level of understanding of the events and activities which must be carried out. If the urge is to use some other more complicated form of logic operator, you shouldask the question: WHY?This usually happens because something a little more complex or different is going on - in which case it must be clearly understood. By shifting to a greater level of detail and sticking to Finish/Start logic links, you force the deeper understanding required which benefits all, as well as the project.More 'complicated' logic operators are generally only used when modeling logic diagrams in project planning software applications, where levels of activity detail may be rolled up.IMPORTANT: Always follow the rule - have the minimum number of activities needed to properly understand the sequencing. Only add more detail if it benefits the level of understanding or future progress control of the project activity list.
Story Boarding
A network diagram communicates the order that activities and events need to take during the implementation of your project. But can soon appear congested and complicated, the larger it gets.
Communication in this context is about UNDERSTANDING. Keeping things as simple as possible helps achieve understanding more effectively.
People will be able to visualise the project sequence if they understand it properly. A very useful tool to aid this process and to provide consistency of understanding within the project team and sponsors, is to adopt a Story Boarding approach.
By Story Boarding, we refer to the use of pictures or diagrams to show where the project needs to be at various points along its timeline.
An example: installing a second chocolate making and wrapping line alongside an existing one, without disrupting current manufacturing or contaminating the product, is a logistical complex construction project. Split the project down into sensible time increments: a week, or even a day at times where tie-in works will be carried out. Using drawings, floor plans and elevations needed for construction, colour in those items that are to be installed in the first time period in a single colour. Use a different colour for the next time period and so on...
This produces a set of pictures, in time order, which clearly show the extent of planned work; its interface with, and effect on, existing manufacturing conditions - a STORY BOARD.
Return of the Post-Its!We referred to the use of post-its as one good way to develop the
Work Breakdown Structure of a project, either by yourself, or as part of a project team exercise. The most detailed levels of the WBS represent the project's initial activity list.
The WBS however does not go as far as identifying the sequence in which activities should be carried out.
Get those completed post-its out again, and separate the initial activity list items.
Back at a wall or other suitable work area, a large white board also works well, place the post-its into a logical sequence of events, resembling the network diagram shown previously.
Use only Finish/Start logic initially, and create additional post-its for new activities required to expand on the detail of the more challenging aspects of the network diagram.
Should you decide the sequence needs to change for some good reason, all that is needed at the workspace is to move the post-its around until you get to the desired sequence of events. No need to waste time redrawing your network on a clean piece of paper, or creating a mess of scribbles as you cross out and redraw activity blocks.
TIP: This is also a great Project Team exercise. Planning should not be done alone, it's a group activity, which then boosts efficiency of understanding and communication, as well as facilitating important buy-in from the whole Project Team.
Conclusion
Network diagrams and network planning are an essential part of planning your projects. It is more fun when carrying it out as part of a Project Team exercise, which also increases the efficiency of obtaining common understanding and consensus of the project work flow: all important BUY-IN.
Combined with Story Boarding, it is an easy way to explain what the game-plan will be to others within the broader Project Team, or other interested stakeholders and sponsors.
