I have been working on different ways to represent overlay networks in reports, presentations and consulting engagements. At this point, I have something workable that I can share with you.

Here is the diagram I’m going to produce using OmniGraffle 6. I guess you could create network diagrams like this in Visio but I don’t use it because it’s unreliable. I hate losing work.

The key to this diagram is that is has perspective to a vanishing point. Easy to do this is to draw two lines to some point, draw a rectangle, then Edit, Shapes, Editable Shape will give you small blue handles to drag around. Move them to make this shape.

The actual shape doesn’t matter too much because duplicating the shape here means that all of the shapes in the ‘stack’ are roughly the same. Do your best to copy what I’ve done here and it should be good. Duplicate a bunch of shapes.

Then distribute them evenly use the appropriate tools. This is the Inspector bar in Omnigraffle showing how to align the object centres vertically and to evenly distribute over a given area.

Then change the colours of each shape element in the stack. Ok, so choosing colours is hard and you probably don’t know how to use a colour wheel (neither do I but I’m working on it). Here I’ve chosen a colour on the bottom row of the OS X Colour picker and each layer is the next colour along. I’ve also set each colour to 50% opacity so that you “see” through the layers. 

The shapes lack coherence when you look at them. They don’t look right, or somehow they are aren’t straight. That’s because the shapes don’t converge on the same vanishing point. The next diagram shows how to add a couple of lines to vanishing point, then using editable points in the shapes to line them up.

Don’t be shy to add more lines to keep everything aligned. See how the purple shape layer isn’t quite straight ? Adding a line will keep that sorted out.

Shapes on the Layers

You might want to represent some network devices on the layers. Obviously, drawing squares or circles isn’t going to work very well. Here is how to create shapes that match the layer

• Pick the layer (each one is unique, remember)
• Duplicate it
• Resize it using the corner shape handles  so that it keeps the same proportions. In Omnigraffle, hit the ⌥ key will resizing with the mouse.

Change the shapes to a nice colour that will contrast against the layer. (OK, so I am not an interior decorator) and then drag it on to the shape.

Now we need to draw some connectors onto shape layers but every time you try to draw a line it keeps snapping to the big layer. Turn off “Allow Connections From Lines”

Draw some connections like this and then use the “Group” function to make single object. This makes it much easier to move around, align & centre in the following steps.

Sometimes it’s worth using a little shadow to create the contrast. The colours are dreadful here (why did I put puce on emerald ? ) but you can see the improvement created.

Now we can bring the layers back together. Align centres, and distribute them evenly again.

And now you have the final result of an aesthetically pleasing overlay network diagram.

Ok. So it is a work in progress. I’ll get the colour and shapes better in the next version.

Other Posts in This Series

1. Free Custom Handwriting Font for Network Designs (14th August 2014)
2. Network Diagrams: Font Selection and Production Context. Choosing Slab or Thin fonts (9th June 2014)
3. Book Release: Tips on Using Visio To Make Network Diagrams (27th March 2014)
4. Network Diagrams: Drawing Overlay Network Layers (14th March 2014)
5. Network Diagrams: Choosing Better and Free Fonts (10th January 2014)
6. My New Diagram Colour Scheme "Old Disco Style" (24th September 2013)
7. On Diagrams and Information (10th September 2013)
8. Colour Blindness, Network Diagrams and Reliability (3rd March 2011)
9. Designer or Engineer, Artist or Painter (19th January 2010)
10. Network Diagrams: Rotating Text on a Line (1st October 2009)
11. Network Diagrams: Tips for Printing from Visio (22nd September 2009)
12. Network Diagrams:Zones on a diagram with Visio shape union (31st July 2009)
13. Network Diagrams: Drawing complex VLAN Networks with IP Addressing (7th July 2009)
14. Network Diagrams: Drawing Freehand Curves (and then fixing them) (23rd March 2009)
15. Network Diagrams:Aligning Shapes (12th March 2009)
16. Network Diagrams:Locking the Background Shape (10th March 2009)
17. Network Diagrams: Labelling an VLAN/IP Segment (9th March 2009)
18. Network Diagrams: VLANs and IP Subnets (8th March 2009)
19. Network Diagrams: Drawing the Background Shape (6th March 2009)
20. On the Art of Network Diagrams and Presentation (4th March 2009)