On EJBs I have an architecture MVC thus:
- serving, he possess client web, EJB1, EJB2
- serving B, possess EJB1
- serving C, possess EJB1

The customer web has access EJB2 passing parameters for a method, this method in EJB2 calls EJB1 in each one the servers passing the same parameters. The return of each execution then is received by EJB2 and this through a calculation decides which the correct reply to return to the customer.
My doubt is the following one:
- when an only customer requests the data everything functions normally, but when I will have some customers having access the EJBs the 0 variable that keeps the return in EJB2 I will not go to be insane person (he will receive resopostas from all the requests)
- are created only one instance of the EJB for all the customers? - how that the return of the method called for the customer returns to this (as that is made)?
One I hug.

I forgive me I do not speak English, I am Braziliam