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When we think of network documentation, we tend to think of a written narrative, a dense tome that even an IT professional is reluctant to dig into. But it doesn’t have to be that way. Graphic diagrams, created with the aid of Microsoft Visio, can convey important information quickly and painlessly. Although many IT pros use Visio, not all of them use it as effectively and consistently as possible. Thus, I’m going to provide some guidance for using Visio to create effective network documentation.

Why use Visio?
A wide variety of drawing tools can produce digital illustrations, ranging from simple ones, such as the Paint program included in Windows, to sophisticated ones, like Adobe Illustrator. But by far the most useful program for creating graphic documentation of a computer network is Microsoft Visio. Not only does it have the built-in tools needed to graphically display network information, but it’s also straightforward and easy to learn. You can show relationships between network devices with a simple, drag-and-drop method that quickly creates a sharp, crisp, professional drawing.

What can you display graphically?
Truly, you are limited only by your imagination in terms of what you can display with Visio. Here are some examples of elements that you can illustrate:

  • Network topology
  • DMZ configuration
  • Systems overview
  • Logical relationships
  • Rack server diagrams
  • Router and switch port assignments

What makes a good graphic display?
To do these kinds of drawings well, you don’t have to be an artist or have a degree in graphic design. But you will need to have some idea of basic best practices for graphic design and visual documentation to communicate information about your network. Let’s take a look at some of these basic principles.

Communicate one idea at a time
Imagine that a company has a new IT manager who wants to see a complete overview of the network. To communicate that information to him, the WAN administrator, the LAN administrator, the backup administrator, and the desktop support supervisor all stand in front of him and simultaneously begin describing their particular aspect of the network. Needless to say, that would not be effective.

And yet probably the biggest mistake that people make in creating graphic network representations is trying to put everything into one drawing. It is the visual equivalent of everyone talking at the same time. Such a drawing often ends up being a confused jumble of information that’s hard to sort out. Information in network drawings needs to be communicated just one idea at a time.

How do we do that? By breaking up the drawing into multiple drawings, each of which shows a separate aspect or part of the overall network. Of course, every network is different, so the drawings are going to vary according to the configuration and what you want to depict. But for a large, enterprise network, you might want to have separate drawings for the following:

  • WAN connectivity—In this drawing, you might show each of the routers, their locations, how they are connected (frame relay, ISDN, dedicated T1, etc.) and perhaps their connection to a switch for each network segment.
  • Network backbone—Here you would illustrate the underlying network backbone at each geographic location.
  • Data center—This diagram would break out the details of a data center/server room, showing servers and their connectivity to switches or hubs. In an organization with multiple data centers, you would probably want a separate drawing for each one. If the network is small enough, you might combine the backbone with the data center.
  • Printer location—This is often done as a floor plan showing locations of printers and the types of printers available.

By breaking down the network into its components and depicting each one separately, the message comes across loud and clear rather than being swallowed up in a cacophony of details. Of course, you may want to include additional diagrams to the ones listed above, such as network segment details, workstation locations, and wireless topology, if your company has adopted wireless networking.

Make it look professional
You don’t have to be an artist to create a network drawing. Visio itself will take care of most of that for you by providing prefab drawing components. But you need to lay out the pieces carefully and thoughtfully so that the drawing is not only informative but looks professional as well. A polished appearance will lend credibility to your work. If your drawing looks unprofessional, why should anyone take the time to look at it? Let’s look at some ways to ensure more professional-looking results.

First, use the network diagram stencils that come with Visio. Click File | Stencils | Network Diagram, and you’ll see several stencils to choose from. Probably the most useful are Basic Network Shapes, Basic Network Shapes 2, and Basic Network Shapes 3D. Each of these stencils offers a variety of networking components, which you can simply drag and drop into your diagram.

You can easily draw lines between network components to represent cables, for instance, using the dynamic connector. This handy tool will attach to a drawing from a stencil at an anchor point and will snap to grid, theoretically creating a straight line. However, that is not always the case, as Figure A, at 100 percent magnification, shows.

Figure A

Take the time to make the lines straight. Usually, you can straighten the line by moving one of the components into line with the other. But there will be times when the straight line falls between the gradations of the grid. In Figure A, for instance, note that if you were to move the server up one grid square to the closest snap point, the line would still not be straight.

When that occurs, simply use the Zoom In feature to increase magnification to 200 percent or even 400 percent, as shown in Figure B. By doing this, you change the gradations of the grid, and you will find that you can make the line straight. Note in Figure B that there is now a finer gradation, with three grid squares where there was only one at 100 percent magnification. Investing the time in fine-tuning your lines will help give your drawings the professional look you want.

Figure B

You should also make sure that your components are perfectly aligned with each other. To do this, you “marquee-select” all the objects (place the mouse pointer at a point above and to the left of the leftmost object, click and drag to a point below and to the right of the rightmost object, and release). Once all the objects are selected, click on Tools | Align Shapes. You will see the dialog box shown in Figure C, offering six alignment choices. Choose the appropriate option and click OK.

Figure C

Make liberal use of labels
A drawing that looks good isn’t much use unless the person who is looking at it can tell what he or she is looking at. You certainly need a title, which you can create with a standard Visio text box, but there is more to it than that. Each item or component within the drawing needs to be clearly labeled. It should have enough information to be useful but not so much that it’s overwhelming.

Exactly how you label items in your drawings depends, of course, on what information you’re trying to communicate. So it’s important to determine that before you even begin your drawing. Each network component found on a stencil comes prelabeled with a generic name such as “Server” or “Router.” You can change that to whatever you want simply by double-clicking on the component. This opens up the label for editing and formatting just as with any other text, as shown in Figure D.

Figure D

If you use lines to represent cable, you may want to label them too, either by double-clicking on a line, or adding a standard text box next to it. However, be careful if you have a lot of cables; you could quickly clutter your drawing and detract from what you are trying to communicate.

Use formatting to communicate information
If you find yourself running into the problem of too many labels, you can use formatting to communicate information. Every component you draw in Visio, whether it is text, a line, or another type of object, can be formatted with the desired color, weight, fill, and so on. Simply right-click on the object and choose Format from the pop-up menu to access these options.

In a network topology drawing, for instance, you probably want to represent the different kinds of cabling in the network, such as 100-Mbps twisted pair and Gigabit Ethernet dual-mode fiber. Rather than label each line that represents a cable, which could quickly clutter your drawing, you can color-code them. Then, just include a legend that identifies what each color represents, as shown in Figure E. If a color printer isn’t available, you might want to format the line styles differently to distinguish them, using a dotted line, a thin solid line, a thick solid line, and so on.

Figure E

You can use Microsoft Visio in a variety of ways to document your network. But however you choose to use it, keep in mind that your top objective is to communicate information. Remember to keep it simple—only diagram one piece of information in each drawing. Decide what details you need to convey, and then use Visio’s tools to build a clear, professional-looking drawing.