Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!ames!pasteur!agate!saturn!sape@cwi.nl
From: sape@cwi.nl (Sape Mullender)
Newsgroups: comp.os.research
Subject: Re: Pointers to Capability based addressing systems??
Message-ID: <9171@saturn.ucsc.edu>
Date: 19 Sep 89 20:58:38 GMT
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iyengar@grad2.cis.upenn.edu (Anand Iyengar) writes:
>	Could anyone suggest good reading in the area of Capability based
>systems?  Pointers to the C-Machine (done in London?) would be especially
>helpful.  Thanks in advance.

You might care to read up on the Amoeba project of Free University and
Centre for Mathematics and Computer Science in Amsterdam.  Amoeba is a
capability-based distributed operating system.  Every object is referenced
through a capability, a 128-bit data structure, containing enough randomness
combined with some cryptographic machinery that prevent guessing or forging
genuine capabilities.  Since objects can only be referred to through their
capabilities, you can't even talk about an object to the system, let alone
obtain illegal access to it.

If there is sufficient interest in the mechanisms of Amoeba I'll be happy
to describe them in comp.os.research in more detail.  They have, however,
already been described adequately in

%T Using Sparse Capabilities in a Distributed Operating System
%A A. S. Tanenbaum
%A S. J. Mullender
%A R. van\ Renesse
%J Proceedings of the 6th International Conference on Distributed Computing Systems
%P 558\-563
%D May 1986

	Sape Mullender