Converged Application Server is a carrier-class Java Platform, Enterprise Edition (Java EE) application server that has been extended with support for the SIP and a number of operational enhancements that allow it to meet the demanding requirements of next-generation Internet Protocol-based communications networks. The Converged Application Server implementation is based on Oracle's widely deployed and time-tested Java EE-compliant WebLogic Server product.

In a typical IP Multimedia Subsystem (IMS) deployment, Converged Application Server fills the role of the IMS SIP Application Server. Figure 1-1 shows the Converged Application Server in the context of the functional architecture for the provision of service in the IMS, as specified by 3GPP TS 23.002, "Network Architecture."

Converged Application Server supports all of the standard Oracle WebLogic Server programming interfaces and facilities, such as Java Transaction API (JTA), Java Activation Framework (JAF), Java Message Service (JMS), Java Naming and Directory Interface (JNDI), Java Database Connectivity (JDBC), and Enterprise JavaBeans (EJB). Converged Application Server also supports the protocols typically associated with a standards-compliant Java EE application server, including Remote Method Invocation (RMI) over Internet Inter-Orb Protocol (IIOP), HTTP 1.1, Lightweight Directory Access Protocol (LDAP), Simple Mail Transfer Protocol (SMTP), Post Office Protocol (POP), Internet Message Access Protocol (IMAP), and SNMPv2.

Converged Application Server then builds upon the base Java EE programming model by integrating a SIP Servlet Container that is compliant with the JSR-359 SIP Servlet API specification. This “converged" container provides an execution environment for applications containing both HTTP and SIP protocol handling components, as well as other protocols such as Diameter.