I've been tasked with doing a network diagram of our offices (8 in total) across two different cities. Our network is all on a single flat subnet (10.1.X.X / 255.0.0.0) and all sites are connected ...

If you are not familiar with Visio, it's used for creating diagrams such as flow charts and network diagrams. What I didn't realize is that you can actually create Visio diagrams from within Excel.

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 ...