Because it uses a 3D engine to get things done, your network diagram would be unique compared to others. We are not sure if it will look the best since the 3D icons are not as smooth or the best ...

Whether you’re called upon to create a network schema, a flowchart, an interface mockup, or an org chart, Gliffy is one online tool that tries to make the process as simple as possible.

But Microsoft also still offers Visio Plan 1 and Plan 2 subscriptions, and those get you extra diagram styles for cross-functional flowcharts and swim-lane diagrams, shapes for network equipment ...