Entities do not provide remote services like session beans, so they are not concerned with the load balancing logic or session replication. JBoss EJB 3.0 persistence layer is based on the Hibernate framework and, as we have learned, this framework has a complex cache mechanism, which is implemented both at Session level and at SessionFactory level.
The latter mechanism is called second-level caching. The key characteristic of the second-level cache is that it can be used across sessions. This differentiates it from the session cache, which only (as the name says) has session scope.
Hibernate provides a flexible way to define cache providers, using the property
hibernate.cache.provider_class, when dealing with a clustered solution. ...