Kensington Personal Firewall review: Kensington Personal Firewall

Business travelers often lack the time to verify the security of every wireless hot spot they use. If you count yourself among this group, check out the handy Kensington Personal Firewall, which can keep your data secure no matter which Wi-Fi network you connect to. Plug the tiny adapter into a USB port on your Windows XP-based laptop, and it proceeds to protect both inbound and outbound traffic on your system. While software-based firewalls such as Zone Labs' ZoneAlarm Pro 5.5 also provide this level of security, your IS team may not allow you to install one of these apps. The Kensington Personal Firewall makes a good, secure compromise.

The 1.8-inch-long Kensington Personal Firewall is about the size of a typical matchbox, so it's likely to get lost among the many other items in your carry-on or laptop bag. However, you can keep closer tabs on it by hooking it onto your keychain with the included ring. We wish the cap were permanently attached to prevent it from vanishing as well. The case itself consists of sturdy brushed aluminum, which emerged unscathed after a few days inside our backpack. The top of the device has a tiny LED that flashes on and off to indicate activity.

Installing the Kensington Personal Firewall is a completely pain-free experience. A bundled hard-copy insert advises you to plug the device into a USB 1.1 or 2.0 port on your laptop. Once you've done that, your system automatically installs the required drivers and the configuration tool in less than a minute. Restart your notebook, and you're ready to roll. The adapter would be even more convenient if you could use it with laptops based on several different operating systems; instead, it supports only Microsoft Windows XP Professional and Home editions.

We were impressed with the Kensington Personal Firewall's bundled configuration tool, which organizes the adapter's plentiful features into a few clear-cut screens. The detailed electronic user guide walks you through each feature, though the device does not ship with even a brief guide to its hardware components. You can use the configuration tool to block or permit specific URLs, activate port scanning and tracking, determine necessary levels of inbound and outbound packet filtering, allow certain applications to send info to the Net, and save different security profiles for the home, the office, and the remote hot spot you access most. True, the built-in Windows Firewall within XP Service Pack 2 also offers some of these features, such as inbound packet filtering, but its lack of outbound filtering and its dubious performance in certain areas may make you feel more comfortable with the Kensington device in place.

In our informal tests, the Kensington Personal Firewall lived up to its data-protection claims. Whenever we plugged it in while connected to various wireless networks, it immediately began notifying us (via small status pop-ups from the system tray) that it was blocking foreign packets that were being sent to our computer. And when we changed the adapter's default yellow-light setting, which allows some traffic, to red, we received no traffic at all (and weren't able to send any ourselves).

Kensington offers a standard one-year warranty and toll-free phone support with the Personal Firewall. However, the phone lines are open only Monday through Friday from 7:30 a.m. to 4:30 p.m. PT. The FAQ section of the company's support Web site returned just a few loosely related hits when we conducted a search on the Personal Firewall. Your only other support option is to submit an e-mail message via the site.