Recently I have started using yEd, a free (not Open Source) graph editor, to produce IT Architecture diagrams.

It is written in Java and runs on many platforms: Linux, Mac OS, Windows… It supports a the graphml file format describing graphs. It provides the most essential visualisation features including

• Boxes
• Arrows between boxes
• Boxes in boxes

The real highlight of the product is the sophisticated layout algorithms it offers. The other key feature is the export of graphs in a variety of formats including: SVG, PDF, JPG, etc

What is it good for?

I am planning to automate the production of diagrams for IT Architectures. This application will not replace sophisticated drawing tools due to the limited graphics capabilities, but the plan is to use it for generated diagrams anyway. Where the tool excels is the variety of layout strategies and algorithms it offers to arrange the diagram elements on the canvas, and it can deal with a large number of elements and produces impressive results.

Why not use Visio?

Although it does not offer the same level of sophistication and representation as Visio, it has the advantage of automating the production of diagrams. I am looking at a variety of input sources and driving those through “good old” XSLT to get the result – graphml file. In fairness Visio also supports XML, however the graphml format (including the yWorks extensions) is far less complicated to process. A big advantage over Visio is the support for ‘box in a box’ structures, in other words containment. Visio can only support ‘box over a box’ which is just an imitation of the structure.