Clients can access Java EE applications in several ways. Browser clients access web applications using hypertext transfer protocol (HTTP). For secure communication, browsers use the HTTP secure (HTTPS) protocol that uses secure sockets layer (SSL).
Rich client applications running in the Application Client Container can directly lookup and access Enterprise JavaBeans using an Object Request Broker (ORB), Remote Method Invocation (RMI) and the internet inter-ORB protocol (IIOP), or IIOP/SSL (secure IIOP). They can access applications and web services using HTTP/HTTPS, JMS, and JAX-RPC. They can use JMS to send messages to and receive messages from applications and message-driven beans.
Clients that conform to the Web Services-Interoperability (WS-I) Basic Profile can access Java EE web services. WS-I is an integral part of the Java EE standard and defines interoperable web services. It enables clients written in any supporting language to access web services deployed to the Application Server.
The best access mechanism depends on the specific application and the anticipated volume of traffic. The Application Server supports separately configurable listeners for HTTP, HTTPS, JMS, IIOP, and IIOP/SSL. You can set up multiple listeners for each protocol for increased scalability and reliability.
Java EE applications can also act as clients of Java EE components such as Enterprise JavaBeans modules deployed on other servers, and can use any of these access mechanisms.