Introduction to Network Mapping

Beyond a certain size networks become difficult to visualize without graphical aids. There are a number of tools to aid in the production of network maps. This article provides reasons why you should be interested in network mapping, as well as an overview of the available tools.

What is Network Mapping

Networks are complex systems, and they are getting more complex all of the time. The larger the network, the harder it is to understand as a whole. Network maps help to make networks more understandable by breaking them down into more manageable chunks. For instance, a very large network can be broken down into a very broad overview. Only the largest offices need be displayed, with the main backbones between them. The network can then be broken down into smaller chunks, each chunk revealing more detail about the network.

One of the downsides to network mapping is that the maps require an investment of time to create. But, more importantly, once they are created require a much greater effort to maintain.

Network maps are an invaluable tool to help new hires get up to speed quickly. Maps can communicate more in a few minutes than a day's worth of talking about the network.

When contemplating modifications to a network architecture, network maps can be invaluable. Not only will your network maps communicate to you what changes are necessary, but they will also communicate to other people too.

Less technical people also appreciate network maps. Often non-technical managers are the ones who need to sign off on network upgrades. If you have a means to communicate more effectively with them, then that may well ease the process of budget approval.

Network Mapping Tools

Network maps needn't be an onerous burden to the network engineer. There are a variety of tools available that will help automate some aspects of creating network maps. More importantly, the tools will also help with the burden of maintaining the maps.

Open Source

Rather disappointingly, there is no head on competitor to the commercial network mapping tools. Tools do exist, but they are not up to the standards of the commercial tools.

A number of open source network management systems incorporate some network mapping functionality. Unfortunately, in cases like Nagios and OpenNMS, they are quite rudimentary.

There is only one dedicated open source network mapping tool that I am aware of (though, if you know better, please leave some feedback). knetmap is a network mapping tool running on Linux utilizing the KDE desktop environment. It is currently in alpha so a production version is unlikely for some time.

Commercial

SmartDraw™SmartDraw™ is a straight down the line graphics program. With the addition of a network library it is easy to create network maps of your network. But don't expect any help along the way. SmartDraw™ will not automate any of the process for you by going out and discovering elements of your network for you.

If you just want to create a few simple ad-hoc maps for the lowest cost possible then SmartDraw™ would be a good choice. It is inexpensive and will produce results quickly. It will however impose a significant burden if you wish to keep your diagrams up-to-date.

VisioVisio is perhaps the best know network mapping tool. Like SmartDraw® it is not a dedicated network mapping tool, but it does include a modest amount of automation in the Pro version. The fact that Visio is now bundled in some versions of Microsoft Office means that it will be available to a lot of network engineers.

netViz™netViz™ started life as a pure network mapping tool. It has since broadened out to become a more generic enterprise documentation solution. netViz(tm) now includes diagramming functions such as relational databases, workflows and org charts amongst others.

Neon LANsurveyor
Neon LANsurveyor is a sophisticated network mapping tool with a high degree of automation. Neon LANsurveyor also includes an intrusion detection system to help identify rogue network users. LANsurveyor is able to probe your network and discover your network architecture automatically. It can probe your switches to discover which switch port(s) a given network node hangs from. Documenting your switches alone can be a nightmare, so any means to automate this process can be a real time saver.

Conclusion

The tool likely to appeal to you really depends upon how you are likely to use your network maps. If you just want to knock up a quick, disposable diagram to explain to your boss how your network is put together, then both SmartDraw(tm) and Visio will likely suffice.

On the other hand, if you want a means to maintain a high degree of documentation about your network, then I would suggest you look at netViz(tm) and LANSurveyor. Both of these tools will make the process of maintaining your network maps much easier.

5 Reasons to Document Your Wireless Network

According to recent ZDNet research, wireless networks are predicted to be the number one networking initiative in 2005. That means more and more IT personnel will be planning, installing, and supporting wireless networks. Those who have experience with wireless projects already know there is a plethora of configuration options and choices that must be made in each one of these stages. Fortunately, there are numerous articles and tools available to aid IT professionals to make these choices. However, what is rarely discussed is the importance of proper wireless documentation. As in any major IT project, documentation should be on the short list of items to carry out. Presented here are five top reasons why documentation of your wireless network is important.

1. Shows you are an IT professional

The top reason to document your wireless network is not a technical one. Webster defines professionalism as "the standing, practice, or methods of a professional, as distinguished from those of an amateur." By following the practice of documenting your wireless network, you are showing that you are indeed an IT Professional.

Don't forget that, as it is in most situations, the key to documentation is to do it early, often, and precisely. Now that you have been reminded of the importance of documenting your wireless network, it is up to you to ensure that the job gets done.

2. One of your best troubleshooting tools

Probably one of the most obvious reasons to document your wireless network is to aid in troubleshooting. Having information readily accessible in the event of problems about access point types and locations, IP addresses, WEP settings, client configuration, channels, etc., can't be over emphasized. In the event that you have to get others involved to help with the real sticky problems, the benefit of an easier transfer of knowledge applies here as well. If permanent changes are made to your wireless network because of the ensuing corrective action, do not forget about change management, and document the modifications.

3. Aids in transfer of knowledge

How many times have you come to a new organization, as either a new IT employee or a consultant, and found that there was not sufficient documentation to get you up to speed on what you needed to know concerning the existing configuration? If you have been on the receiving end of this exchange then you understand the importance of having proper documentation. Some hesitate documenting their wireless configuration, thinking that possessing the knowledge in their head will make it harder to replace them. On the contrary, documenting your wireless network can actually make you more "promotable" by ensuring that decision-makers know an easy hand-off can be made in the event someone has to take over your old position.

4. Core of change management

There is an old axiom that states that you must know where you are before you can know where you are going. Transferring this notion to the topic of wireless networks, it tells us that before changes are made, the current configuration should be documented. This is very important considering that change is inevitable in our field, and within the wireless arena, the field is changing even faster. Yesterday it was 802.11b, today 802.11g, and, tomorrow, who knows? If it's not the access points that are changing, it's the security level and configuration. The initial documentation you created during your wireless site survey can serve as a reference point or baseline for the changes sure to come along.


5. It's a necessary component of a proper site survey

Site surveys are fundamental tools for those who deploy wireless networks. The ultimate goal of a wireless site survey is to provide enough information to determine the number and placement of access points that afford sufficient coverage throughout the building. Before a proper site survey can be performed however, some type of floor plan is necessary. This may come from a set of building blueprints or, if no blueprints are available, a floor plan drawing that depicts the location of walls, walkways, and other relevant information. At a minimum, the planned location of access points should be documented on the floor plan or building blueprint. By doing this, you ensure that you have completed a thorough site survey and have taken the first step to documenting your wireless configuration.