This image shows two Oracle Application Server clusters. The first is a 10.1.2 OracleAS Cluster with two 10.1.2 middle-tier Oracle homes within the cluster. Within each Oracle home in the cluster, the FAQApp is deployed on an OC4J instance. This represents the OracleAS Clusters model, where you deploy an application, such as the FAQApp, to one middle tier in the OracleAS Cluster, and then it is automatically deployed to other middle tiers in the cluster.

The second cluster in the graphic is a 10.1.3 cluster. This cluster also has two middle-tier Oracle homes. As with the 10.1.2 model, each middle-tier Oracle home contains an OC4J instance. However, in the 10.1.3 Oracle home, the two OC4J instances are also within a common group. The FAQApp is deployed to the group, which encompasses both OC4J instances in the cluster.

A line with an arrow shows how the FAQApp deployed on one of the 10.1.2 OracleAS Cluster Oracle homes can be rebuilt and redeployed on the group within the 10.1.3 cluster.