If your server is running IIS on Windows NT or 2000, consider locking it to outside attack with WatchGuard AppLock/Web 1.0—an innovative application based on WatchGuard ServerLock 1.1

Like ServerLock, AppLock/ Web makes it possible to protect a server at the OS kernel level. When the program is in locked mode, neither an attack nor a virus can make changes to protected files, including the Registry and critical IIS files. But unlike ServerLock, AppLock/Web does not extend the lockdown to enterprise-wide applications, instead sticking to IIS content that it discovers automatically. Or you can select from more than 200 Web file types, such as HTML, CGI-BIN scripts, images, and sounds.

Setting up AppLock/Web was effortless: We entered a registration key and decided on a secure password. A reboot let us open the simple interface, enter the password, and click Lock the Server. The program then looked for new Web content.

Clicking View/Edit Protections on future log-ons let us deselect any files we wanted unprotected—useful for, say, modifying certain files while keeping the rest locked down.

A locked or unlocked padlock icon in the system tray indicates the state of the server. In lock mode, we could open files but couldn't so much as change a bracket in a protected HTML file. When we ran a couple of hacker applications developed just for IIS, they did manage to get in, but their effects were nullified by AppLock/Web's write protection.

The only potential security flaw we could find in AppLock/ Web was that the password recovery utility that gets installed on your server has a very obvious name. But this is a threat only if an attacker has physical access to the machine.

You'll have to pair AppLock/ Web with traditional antivirus and intrusion detection software if you want to get details on attack origin and type. AppLock/Web simply notes in the Windows Event Log that an attempt on a protected file was made. But AppLock/Web will be doing the real protecting, while using less than 2 percent of CPU resources. AppLock/ Web is ideal for small or midsize businesses that need to protect IIS content.