[cap-talk] Capability systems list (was: Re: ... fear from capabilities?)

Jed Donnelley capability at webstart.com
Sat Jul 14 04:32:10 EDT 2007

At 10:46 PM 7/13/2007, Jonathan S. Shapiro wrote:
>On Fri, 2007-07-13 at 14:25 -0700, Jed Donnelley wrote:
> > 1966: Dennis & Van Horn paper - MIT
> > 1967: PDP-1 Supervisor - MIT
> > 1967: Magic Number Machine - University of Chicago
> > 1968: CAL-TSS - Berkeley
> > 1969: System 250 - Plessey Corporation
> > 1970: CAP - Cambridge University
> > 1971: Project SUE - University of Toronto
> > 1971: Hydra - Carnegie Mellon
> > 1972: RATS - Lawrence Livermore
> > 1973: Actors - MIT
> > 1973: PSOS - SRI
> > 1975: StarOS - Carnegie Mellon
> > 1975: GNOSIS/KeyKOS - Tymshare
> > 1976: Monads - Monash University
> > 1978: System/38 - IBM
> > 1978: NLTSS - Lawrence Livermore
> > 1980: SWARD - IBM
> > 1980: PDP 11 operating system - University of Texas
> > 1981: Amoeba - Free University Amsterdam
> > 1982: iAPX 432 - Intel
> > 1982: Password-Capability System - Monash University

I notice a system that was omitted in the above list, DEMOS, e.g.:

F. Basket, J. H. Howard, J. T. Montague,
"Task Communication in Demos",
Proc. of the Sixth Symposium on Operating System Principles,
Purdue University, 1977, pp. 2331.


Powell, M. "The DEMOS File System", Proceedings of the Sixth
Symposium on Operating Systems Principles, ACM, Nov 1977. pp 33-42

DEMOS was another system that never came to full production use, but
quite a lot of implementation and testing work was done on it.
As far as attention goes, it got much more than NLTSS that ran
in production for over 10 years!  DEMOS helped Forest Basket get
quite a high level position at SGI.  I would also say that, despite
not going into production, DEMOS was moderately influential.

Note that DEMOS had a "do not copy" bit in it's capabilities - which
they referred to as "ports".

Are there others that were omitted?

Hmmm.  I wonder if the S1 system at LLNL should be on this list.
I don't have time to look into that now, but perhaps at a later time.

>Note: System/38 is more popularly known as AS/400.
>This is an important list. Ask yourself which of these systems received
>positive *mainstram* attention. The *only* one I know about is S/38.

Of course the amount of attention they received varied,
but I would say that in the research community the Hydra
system garnered at least a reasonable share of attention.  It
was one of the most talked about systems of the day, many
publications, etc.  It was the system that started CMU on
the road to it's reputation as an IT powerhouse.

It may be that the capability aspect of Hydra was not
particularly emphasized, but it was generally recognized.

>Amoeba was not a protected capability system.

By that I take it you mean it used a capabilities as
data model - as did NLTSS and Monads.  Capabilities as
data was still sufficient for inclusion on the above list.

>Cal/TSS was never finished.

Right, but it did receive more than it's share of attention.
It started Butler Lampson on his way if nothing else.  It
got him to BCC and thence to PARC.  When you say "finished"
I assume you mean put into production?  There is of course
the issue of applications needed for the OS's API.  NLTSS
picked up it's set from LTSS.  There was considerable
development for GNOSIS/KeyKOS from their limited community.
There was quite a mix among the rest.

Of course Mach falls after the end of the above list, but it was
quite influential and I consider it a capability based system - though
also saddled with having to emulate a user/ACL based system, Unix.

--Jed  http://www.webstart.com/jed-signature.html 

More information about the cap-talk mailing list