local interface vs remoter interface.

[Sujatha Kumar]

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.

[Seema Manivannan]

Your question is very well answered here. http://www.onjava.com/pub/a/onjava/2001/05/10/ejb.html

Thanks.