Yes, you are right the emphasis is on authorization not on authentication.
You should know a bit about the EJBContext.getCallerPrincipal() in the different
EJB types and what the the @RunAs annotation does with the authenticated user (e.g is the principal name still the same or not)
The obvious trick question related to this is whether the EJBContext.getCallerPrincipal() would return null or an empty Principal when the user is
unauthenticated.