Agent software sits on individual computers and monitors the use of fingerprinted data. It will log, alert on, or block inappropriate actions, such as unauthorized e-mailing or copying the data to a USB drive.
McAfee became the 900-pound gorilla in the space when it announced its Data Loss Prevention Host at the RSA conference. Provilla, a start-up, also launched a host-based EP called LeakProof in early 2007. These new products join existing solutions from companies such as Oakley Networks and Vontu.
While McAfee isn't the first to market, its presence signals that enterprise buyers are ready to spend significant money.
Look for brand-name competitors to respond by launching their own products or by acquiring smaller players.