# EJB 3.0 and EJB 3.1 architecture

This topic provides a high-level overview of the distributed component architecture defined in the Sun Microsystems Enterprise JavaBeans™ (EJB) version 3.0 architecture specification.

Enterprise JavaBeans is a standard server-side component model for distributed business applications. The EJB specification is part of the Java™ Platform Enterprise Edition.

EJB 3.0 and EJB 3.1 makes it much easier to develop EJBs, using annotations rather than the complex deployment descriptors used in version 2.x. The use of home and remote interfaces and the ejb-jar.xml file are also no longer required in this release. They are replaced with a business interface and a bean class that implements the interface.

For more information about EJB 3.0 and EJB 3.1 specification go to the following Web site: http://java.sun.com

- Plain old Java objects
  Although POJOs existed before, they play a more important role in the programming methodology of Java EE 5. Now, you can now create EJB applications with persistence capabilities by using enterprise beans and entities created from POJOs.
- Differences between EJB 3.0 and EJB 2.1
  Compared to EJB 2.1, EJB 3.0 simplifies the process of creating Enterprise JavaBean applications.

Parent topic: EJB 2.x application development