It is said that "local interface / colocated beans do not need to use the network to communicate, since they are in the same JVM. Where as remote interface makes use of network to communicate."
Consider a Scenario: ======================= Servlet --> Session Bean --> Entity Bean. (Session and Entity bean are using remote interface) Servlet makes the remote call to Session Bean, and Session bean calls Entity Bean. My question: =============== Here we see that both Session Bean and Entity Bean are located in the same container, then why there should be a delay in calling Entity bean from Session Bean. How does local interface help in the above scenario. Note: =========== I understand that in co-located beans the objects are passed by reference and not by value. Could anyone give a clear explaination on this topic. Your help is appreciated.