Apache Tomcat is an open source web server and servlet container developed by the Apache Software Foundation (ASF). Tomcat implements the Java Servlet and the JavaServer Pages (JSP) specifications from Sun Microsystems, and provides a "pure Java" HTTP web server environment for Java code to run in.

This chapter describes how to implement two-factor authentication in Tomcat using the DualShield Tomcat Valve and the DualShield SSO service provided by the DualShield Unified Authentication Platform.