Apache Tomcat

Tomcat 6.0.x

Performance optimizations and reduced garbage collection
Refactored application deployer, with an optional standalone deployer allowing validation and compilation of a web application before putting it in production
Complete server monitoring using JMX and the manager web application
Scalability and reliability enhancements
Improved Taglibs handling, including advanced pooling and tag plugins
Improved platform integration, with native Windows and Unix wrappers
Embedding using JMX
Enhanced Security Manager support
Integrated session clustering
Expanded documentation

JMX based administration features
JSP and Struts based administration web application
New Coyote connector (HTTP/1.1, AJP 1.3 and JNI support)
Rewritten Jasper JSP page compiler
Performance and memory efficiency improvements
Enhanced manager application support for integration with development tools
Custom Ant tasks to interact with the manager application directly from build.xml scripts

User manager, conf/tomcat_user.xml

<tomcat-users>
  <role rolename="manager"/>
  <user username="tomcat" password="tomcat" roles="manager"/>
</tomcat-users>