Sustainable Softworks' IPNetMonitorX 1.4 is an all-purpose tool for troubleshooting network connections. Built primarily for network administrators and power users, it provides a wealth of information about how your computer connects to the outside world.

Many of IPNetMonitorX's 17 tools are freely available as part of OS X, and you can access them via Terminal or the Network Utility application. So why would you pay for IPNetMonitorX? Because it does a fine job of unifying these tools within a consistent user interface. It also offers capabilities that the free tools don't. And IPNetMonitorX augments existing OS X tools. OS X's Traceroute tool allows only one type of trace, UDP; IPNetMonitorX adds two more types -- ICMP and Record Route, which give you the flexibility necessary to get through firewalls. OS X's version of the Port Scan tool lets you conduct only TCP scans, but IPNetMonitorX lets you conduct TCP and UDP scans.

The Little Things

Getting started with IPNetMonitorX takes about a minute. Once the program is loaded, you launch the tools from a slender floating palette. The developers worked hard to add touches of luxury. For example, after doing a ping test to a remote computer, we launched the Link Rate tool to test the speed of our connection. The program was smart enough to preload the address of the remote computer we had worked with earlier. Even better, the tools share a list of computers that you connect to often.

If you use the Ping and Traceroute tools often, you'll certainly appreciate them. For example, the program autocompletes addresses as you type. From the Traceroute window, you can select any returned address and press Command-option-W to launch a Whois lookup. In addition, the Ping tool can play a sound for each successful ping, which can be enormously useful when you're trying to connect a computer to your network but aren't sure which cable to connect in your wiring closet.

Diagnostic Abilities

IPNetMonitorX also adds useful tools of its own, including Address Scan, DHCP Lease, and Link Rate. But despite this program's name, very few of its tools will actually help monitor your network -- they are mostly diagnostic. The Monitor tool provides a graphical view of traffic flows, but it's limited to your local computer.

New to this release is the AirPort Signal Tool, which is supposed to measure the amount of interference (signal-to-noise ratio) in your wireless network. However, it's not as useful as Apple's new AirPort Management Tools 1.0 (in the AirPort 3.4 update), and it's especially weak for newer laptops because it doesn't work correctly with AirPort Extreme cards. The new Apple tool is graphical, gives you a lot more information about your wireless network than the AirPort Signal Tool, and works with AirPort Extreme.

Macworld's Buying Advice

IPNetMonitorX 1.4 brings solid improvements to OS X 10.3's networking tools by enhancing the user experience and adding capabilities. If you spend a lot of time troubleshooting network connections, IPNetMonitorX will be a valuable addition to your bag of tricks.