Actions speak louder than words, and testing a very large Active Directory (AD) yourself is a good way to gauge the scalability of the directory. You can search our phone number database at, this site uses Lightweight Directory Access Protocol (LDAP) searches activated through Active Server Pages (ASP) to interrogate AD. A modified version of the load program groups the phone number data by state, then groups the data by town to create a better organizational unit (OU) model than that used for the original test. Searching is typically rapid, as you'd expect from an 8-way server. Our search for "Karen Forster" (Windows 2000 Magazine's editor in chief) found nine phone numbers in less than a second. That response time isn't bad considering that we conducted the search from Ireland and the AD scalability demo Web site is in Seattle.