Being a network administrator can be a tough job, but having the right tools makes life a lot easier. These five free utilities can definitely simplify things. You might not need them every day, but you'll be glad you have them on hand.
InSSIDer is a handy tool for anyone who uses a wireless network. This utility is designed to show you all the wireless networks in the area and their signal strengths. The cool thing about this tool is that the data it collects is cumulative, so you can even analyze networks that show up only occasionally.
Perhaps the most useful information this utility provides is the wireless channels that are in use. All too often, wireless networks provide poor performance in spite of good signal strength as a result of another network on the same channel. By analyzing the channels that are in use and making any necessary adjustments, you can ensure optimal wireless performance.
2: LAN Speed Test
LAN Speed Test is a free tool that is designed to measure network performance. It works by building a file, uploading the file, and then downloading the same file. This process is used to measure things like the packet length, the time required to complete the process, and the transfer speed (for both upload and download). What's really nice about this tool (besides the fact that it's free) is that it is simple to use and it works with wired and wireless networks.
3: Angry IP Scanner
Every good network administrator needs a good port scanning utility. However, my experience has been that such utilities can sometimes be elusive. Most of the port scanners I have found over the years have been either single purpose or overly complex. Angry IP Scanner provides a good middle ground.
As you would expect, Angry IP Scanner can scan your network for open ports -- but it also tests the network's ability to resolve host names, scans for dead machines, and performs a few other basic functions. The data that is collected can be exported in a variety of formats.
Although LAN Speed Test is a good tool for measuring throughput, it is more of a diagnostic tool than a bandwidth monitor. If you need to track bandwidth consumption over the long term, you might try a free utility called NetWorx. It compiles a number of bandwidth usage statistics and even allows you to configure various alerts so that you can be notified when bandwidth consumption exceeds a predetermined threshold. You can also configure alerts to disconnect a session that is consuming excessive bandwidth.
Rounding out this list is Ethereal, a free protocol analyzer you can use to monitor the packets that are flowing across your network. Ethereal does have a few shortcomings. It hasn't been updated in about five years, and it lacks some of the more advanced features found in commercial protocol analyzers. Even so, Ethereal is free and relatively easy to use. And in spite of being dated, Ethereal contains most of the features you'd expect to find in a lightweight protocol analyzer.
Do you use the apps listed here? What other free admin tools do you consider essential?
Brien Posey is a seven-time Microsoft MVP. He has written thousands of articles and written or contributed to dozens of books on a variety of IT subjects.