dladm

OpenSolaris supports virtual networks using virtual interfaces connected with virtual switches.
This feature was introduced with Project Crossbow in OpenSolaris 2009.06.
To visualize the internal network(s), I created a perl script which takes the output of dladm show-link and dladm show-linkprop -o link,value -p zone and generates a dot-File, which then can be rendered using Graphviz.