>An actor can map the memory of another actor provided it knows its
> >identifier (the "capacity" of this actor in C5 parlance), which is
s/capacity/capability/
>128-bits wide.
>
> Are you saying an actor can access another actor's memory without
> permission of the other ? It only needs to know its ID ?
Sure! Just like someone else can access your credit history, etc. -- all they need to know is your full name, social security number, etc.
Hence the reason that the capability is so "wide" -- unless it is disclosed to you (by the process or it's parent -- or some other entity "in the know"), you theoretically have to *guess* what it is. That could take you a *very* long time (depending on your guessing strategy and the actual value of the capability).
Note that other OS's treat the capability as a true token, held by the OS on your behalf. So, "guessing numbers" will *never* allow you to gain access to the resource -- the token isn't "just a number".
(hmm, maybe time to get the full Jaluna-2 docs ....)
--don