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Visualizing Your Network

A Network Blueprint

One of the best pieces of advice I received while I was preparing for my CCIE lab back in 1999–2000 was to use a large sheet of paper to draw out and document the lab scenario I had to build. I started using 11x17 (tabloid) paper to draw up the network and keep track of most of the important details like addresses, ports, and interconnectivity. It was a godsend for both configuration amd troubleshooting.

This is still something that I find invaluable to this day - partly because I’m a very visual person, and partly because I just don’t have a good memory for details. My preference for large paper was reinforced several years ago at an Edward Tufte seminar where he expounded on the value of resolution of paper and also extolded the virtues of a larger “canvas” and how our minds can better use the extra visual space to see both patterns and the big picture. (I’m likely butchering his actual points, but that’s how I remember it.)

The diagrams I prefer to use are not high level “marketechure” diagrams, but ones meant to illustrate and document the intricacies of the solution to be implemented and/or supported. I find these diagrams incredibly useful for both thinking through and configuring implementation details, and for troubleshooting problems. In that sense I treat these very much like an architect treats a blueprint for a contractor to build a house.

Keys to building a diagram

For high-level network diagrams I tend to use vendor Visio stencils (if available) - either the Cisco “Hockey Puck” style, or the equipment specific “front/back” views. These stencils provide a standard visual language that most in IT are familiar with, and therefore provide a great executive level view. I find however that it is hard to get a lot of the detail that is really helpful during implementation on these types of diagrams. These diagrams are most useful as high-level overviews in proposals and presentations and are typically sized at 8.5x11. Too often though in order to fit information into smaller/denser footprint much of the necessary complexity gets lost. It is too easy to simplify connections or components to make it look good in smaller space but thereby losing detail that becomes important when visualizing the actual deployment or trying to find a problem.

Marketecture diagram
“Marketecture” diagram

For implementation/support “blueprints” I prefer to use standard basic shapes such as rectangles and circles as it allows me to add that additional level of detail. From simple items such as hostname and management IP addresses to interface numbering I find it is much more readable on a simple diagram.

Detailed map
Detailed map

Keys to building good diagrams…

Here are some of the guidelines that I use when building diagrams that I feel make them much more useable:

  • Go big – use as big a “canvas” as you can. We are fortunate to have a printer at the office that can print 11x17 Tabloid size diagrams, so that has become my default size. I find that starting a diagram in Visio or Omnigraffle (my preferred Mac diagramming tool) on a large size gives me plenty of room to make a diagram that doesn’t seem to busy. These diagrams usually will look just as good when printed out on standard 8.5x11 paper too, and Visios or PDFs will scale automatically to print on smaller paper. Even for a hand-drawn diagram, an 11x17 page provides plenty of room to draw and then annotate liberally.
  • Use whitespace – try not to cram too much into a diagram and leave plenty of whitespace. This is especially useful when using diagrams for troubleshooting as it leaves plenty of space for handwritten notes.
  • Color code – use standard color coding for components such as network connections. I typically use a light blue for 1 Gigabit Ethernet links, a dark blue for 10 Gigabit Ethernet links, orange for Fibre Channel, etc…
  • Indicate physical locations – many LAN diagrams I see don’t differentiate between locations within a building or campus. The diagram will simply show a core switch and any number of access switches, when in actuality some access switches might be in the same rack as the core switch, while others could be several buildings away. That is useful information to have when both implementing and troubleshooting. A simple labeled box around a stack of switches can help immensly.
  • Keep it simple and focused – there is a fine line between useful detail and overloading a diagram. If a subsystem (say a firewall/dmz/Internet solution) has a lot of complexity then its probably best to have a separate diagram for just that detail, rather than trying to incoporate that detail into a big picture LAN topology.
  • Draw your own diagram – even if someone else has drawn a diagram, I find it useful to do my own. It’s not that my diagrams are better, but the process of drawing it helps me think through the specifics, and maybe even see some detail that was not apparent on the original.

I see too many environments that don’t have or maintain accurate diagrams and documentation. A good diagram can be invaluable when maintaining or troubleshooting an environment. Although I focus mostly on network diagrams I think these same principles can apply to all IT system out there.


My iPad Essentials

The new Retina Display combined with LTE in the new iPad (3) was justification enough for me to pre-order a replacement for my old 1st-gen iPad. Quick review … I love it. The display is as gorgeous as advertised, and it is faster and lighter than my old iPad (1). A quick speedtest using LTE in Albuquerque gave me 11Mbps downloads – I can live with that.

A simple iCloud restore of my old iPad on to the new one worked very well (never had to connect up to iTunes). Now I think I should take the opportunity to reconsider all the apps I have installed, and whether I use them. So taking a cue from David Sparks’ Home Screens series on MacSparky I thought I’d look at my own homescreen.

My homescreen
My homescreen

Go-To Apps

The apps I reach for most often on my iPad fall into the following categories:


The iPad of course excels as a reading device, especially with the crispness of the new Retina Display[1]. For eBooks I use both Kindle and iBooks , but mostly Kindle. I am also a heavy Instapaper user - links I come across in Twitter or otherwise during the day get saved to Instapaper so that I can read them at a more convenient time. The sharing features in Instapaper are great - it is easy to post quotes I like to my Tumblr, to Evernote, or create a task in OmniFocus.

I follow way too many blogs via Google Reader (though I use it only to keep things in sync between devices). My RSS reader of choice is Reeder, though sometimes when I want a different view (mostly to browse feeds I don’t actually read regularly) I’ll dip in using either Feedly, or Flipboard.

The iPad is also great for reading PDFs, and for that I prefer Goodreader. Within Goodreader I can sync or just download folders via Dropbox (and now iCloud, but maybe more on that another day), and I can highlight and annotate the PDF files. A “must-have” app in my opinion.


Writing is such an interesting activity for me. It is definitely something I need to do in a flow state and getting into that state can be difficult. On the other hand I like being able to change my environment when either an idea or motivation strikes me, or just to get a change of scenery if I’m stuck. For these reasons I’ve switched to a text-base + Dropbox system for managing my writing projects.

On iPad my current text editors are Elements, Nebulous, and Byword. Why three and not just one? Each has it’s strengths and weaknesses, so I’ll pick whichever seems better suited to the situation.


I prefer the iPad/iPhone over the desktop for Twitter and Facebook over the desktop. My current favorite Twitter app is Tweetbot - just excellent all around (and I recently discovered that it works with the TweetMarker service to sync timelines across devices - so awesome).

I will also often grab the iPad to check email even if I’m also working on laptop so as to not disrupt what I’m doing. Apple’s Mail app works well enough, but after playing a bit with Sparrow on iPhone I’m hoping that app will come to the iPad soon.

Thinking and Planning

The other area where the iPad excels for me is thinking and planning.

Mind mapping is a great way to organize thoughts on projects, writing and anything that has more that a few moving pieces, and for mind mapping iThoughtsHD is excellent. In addition to a great interface it imports/exports many different file formats and syncs with Dropbox. [2]

If I want a more traditional outline view OmniOutliner fits the bill (and you can move between iThoughtsHD and OmniOutliner easily using OPML file formats).

The iPad is a great environment for planning my workday/week. I use Calvetica to get an overview of my calendar/schedule. With it I can get nice daily, weekly, or monthly overviews of my work calendar (synced from Exchange) and personal (via iCloud).

Projects and tasks I manage using OmniFocus, which also syncs nicely between iPad, iPhone, and Mac. There is a pretty steep learning curve to OmniFocus, and despite many great resources available I have yet to fully master it.


The one area I haven’t really found a go-to app yet is for diagramming. I have downloaded quite a few, but none have stuck yet, so I’ll continue to try new ones until I find one that works (or maybe diagramming is best kept for paper for now).


And just a few miscellaneous apps I reach to from time to time.

  • Evernote – store notes, links, and pdfs to be synced across devices. Used a lot less these days since moving to text files and dropbox.
  • Wolfram Alpha – search app for calculated information - can be used for looking up everything from conversions, IP subnet calculations, or Scrabble words.
  • BeejiveIM – Instant messaging client
  • Soulver – a unique calculator app
  • Pcalc – a more traditional calculator, with RPN support
  • SubnetCalc – and IP subnet calculator
  • Prompt – an SSH client


Looking at the other apps on my iPad I don’t see any obvious candidates to jump to the front page, so I guess this list will stay static for a little while longer.

  1. Except when reading digital magazines that have been rendered as non-retina bitmapped text - they look a lot worse.  ↩

  2. Dropbox is really the glue that makes then iPad useable for creative tasks such as writing and mind mapping, and not just consumption. iCloud may fill this gap in the future, but it’s not quite there yet.  ↩


Cisco subnetting game

Want to practice your IP subnetting skills? Check out Cisco’s IP subnetting game.


Quicktip: Evaluating Cisco IOS releases for deployment

I had thoughts of someday writing up a methodology to evaluate Cisco IOS releases for deployment, but Greg Ferro has already done a nice job at Etherealmind so check it out.


Quicktip: Nexus 7000 Minimum Recommended Releases