From: ino@is.s.u-tokyo.ac.jp (Shigekazu Inohara)
Newsgroups: comp.os.research
Subject: Summary: capability-based filesystem?
Date: Sat, 25 Jul 1992 00:46:33 GMT
Organization: Dept. of Information Science, Univ. of Tokyo, Japan.
NNTP-Posting-Host: ftp.cse.ucsc.edu
Originator: osr@ftp

Here is the summary of answers I received to my question in article
<141qj1INN8ap@darkstar.UCSC.EDU>:

  >I am studying capability-based protection, and a question came to my
  >mind: "how to build a filesystem with per-file capabilities?"
  >
  >In the case of ACL-based protection, client-side programs need to have
  >nothing, because the filesystem determines what files the program can
  >access only from the identity of the programs (e.g. their owner, in
  >UNIX).  In the case of capability-based protection, however,
  >client-side programs have to provide the capability for the file that
  >they wish to access.  How can they have the capability, if a
  >filesystem is the only public name space in the system?

Many people gave me precious information.  In addition to several
people that followed my article on the comp.os.research, many e-mail
replies came to me.  I have not in fact expected to receive so many
people's hearty answers.  Thank you very much.

----------------------------------------------------------------------
The following people suggested that the Amoeba system by Andy
Tanenbaum's group solved the above question.

ast@cs.vu.nl <Andy Tanenbaum>
dfk@wildcat.dartmouth.edu (David Kotz)
douglis@MITL.COM (Fred Douglis)
philw@research.att.com
"Samuel S. Paik" <d65y@crux1.cit.cornell.edu>
shizgal@cpsc.ucalgary.ca (Irvin Shizgal)
kaashoek@frans.cs.vu.nl

Amoeba's documents can be anonymous ftp'able from 

	Site	Name		  Internet address	Directory
        ----	----		  ----------------	---------
	VU	ftp.cs.vu.nl	  192.31.231.42		amoeba
	UCSC	midgard.ucsc.edu  128.114.14.6		pub/amoeba

----------------------------------------------------------------------

Timothy.Roscoe@cl.cam.ac.uk gave me a pointer to the Cambridge CAP
computer and its operating system.

 Author:         Wilkes, Maurice V., Maurice Vincent
 Title:          The Cambridge CAP computer and its operating system; M.V.
                 Wilkes, R.M. Needham
                 New York: North Holland, 1979
                 x,165p; 24cm
 Series title:   Operating and programming systems series; 6
                 The computer science library
 Subjects:       CAP (Computer)
 Other entries:  Needham, R. M., Roger Michael


----------------------------------------------------------------------

maeda@isl.rdc.toshiba.co.jp (Ken-ichi Maeda) discussed capability list
passing.

-----------------------------------------------------------------------

ken@cs.cornell.edu (Ken Birman) taught me about CAL-TSS system,
developed by Butler Lampson.

----------------------------------------------------------------------

miller@SCTC.COM (Steven M. Miller) also suggested the job of a
capability server.

----------------------------------------------------------------------

cwm@beta.lanl.gov (Christina W Mercier)'s e-mail described the
Kerberos authentication approach and Lawrence Livermore National Lab's
file system.

----------------------------------------------------------------------

li@oracorp.com suggested to read 

	L. Gong, ``A Secure Identity-Based Capability System'', in
	Proceedings of the IEEE 1989 Symposium on Security and Privacy,
	Oakland, California, May, 1989, pp.56-63.

----------------------------------------------------------------------
--
Shigekazu INOHARA	Dept. of Info. Sci., Faculty of Sci., Univ. of Tokyo
			7-3-1 Hongo Bunkyo-ku, Tokyo 113, Japan
			ino@is.s.u-tokyo.ac.jp