We are getting ready to make a major revision in our Web Application architecture which currently is running on JBoss 4.2. At first we were looking at moving from 4.2 to JBoss 6 but after some research tomcat may be a better solution for us.

My first question is their anything that JBoss can do that tomcat cannot do assuming you are using the correct plugins. We do not really use EJB's in our solution and it would appear there are simple plugins for web services, JMX and other features.

Tomcat appears to have much better support, faster upgrade cycles and many, many books.

Since there is less to the system it also seems much easier to support from an admin point of view.

What am I missing?

The main features we want to enable are better clustering support and session replication / persistence.

We will consider other application servers as well such as Glassfish / Geronimo.

quote form a web article:

Apache Tomcat is the world’s most widely used web application server, with over one million downloads per month and over 70% penetration in the enterprise datacenter. Tomcat is used to power everything from simple one server sites to large enterprise networks.