From: jon@alpha.ee.ufl.edu (Jon Mellott)
Subject: Re: The NT file system
Organization: EE Dept at UF
Date: Fri, 24 Jul 92 13:39:53 GMT

In article <1992Jul23.180617.24256@njitgw.njit.edu>, dic5340@hertz.njit.edu (David Charlap) writes:
|> In article <1992Jul22.171518.22291@eng.ufl.edu> jon@alpha.ee.ufl.edu (Jon Mellott) writes:
|> >In article <1992Jul22.160800.4154@nuscc.nus.sg>, eletanjm@nuscc.nus.sg (TAN JIN MENG) writes:
|> >|> CIVENBAH@mizzou1.missouri.edu writes:
|> >|> : ...how about a stand-alone computer used by many students at a
|> >|> : school.  Each has his homework password protected from all other students.
|> >|> 
|> >|> That is **NO** protection at all! For secure systems, you need a
|> >|> physically secure server storing all the sensitive data. Access is then
|> >|> from client workstations. For file protection, you really need a
|> >|> physically secure file server.
|> 
|> >Eh? There are varying definitions of security. In either case, there is 
|> >no requirement for a *file server*. There is nothing special about that
|> >network interface which provides security. Files can be stored locally 
|> >on a machine and be secure -- all you have to do is prevent the users of 
|> >the machine from being able to compromise the security of their
|> >workstation. 
|> 
|> This is much easier said than done.  Have you ever tried to disable
|> booting from floppies without disconnecting the floppy drives?  
|> 
|> This point aside, a school environment is no place for a file system
|> where everybody can get at it.  Have you ever seen the abuse that
|> school computers get?  The machine wouldn't survive a minute!
|> 
|> Ignoring the abuse factor, if you have more than a few students, there
|> will lines out the door to get access to the machine.  In high school,
|> there were five Apple clone computers, and it wasn't nearly enough for
|> everyone to get their work done.  This was with simple floppy-based
|> systems.  The only ones who got anything done were the people who had
|> compatible computers at home.
|> 
|> In other words, you're going to need many workstations, or the
|> students will end up using floppies, doing work at home.  Either way,
|> protecting a local hard drive will do little good, aside from keeping
|> immature students out of the system files (del c:\*.*)
|> 
Having spent some of my undergrad years administrating a public computer 
lab I can tell you a few things. First, if the lab is staffed (I've heard 
that some schools don't staff public computer labs -- to my mind that is 
not very bright), then physical security of every machine (including 
file servers) can be insured. Secondly, even if the students have no 
malicious intentions they usually manage to whack configurations all by 
themselves. The most dangerous users are those that know a little 
(i.e., enough to be dangerous). Before we did some vodoo with DMPC we used 
to routinely have hard drives whacked. "Try this: format c:".

|> It's also a well known fact that no matter how well you secure the
|> software, if the file server is physically accessible to outsiders, it
|> can be compromised quite easilly.  At the worst, someone could just
|> steal the computer out of the room!
|> 
|> For any decent security, the file server must be in a different
|> (locked) room away from the workstation.
|> 
Again, if the lab is staffed then this shouldn't be a problem. The workstations 
have the same high level of security as the file server. To an educational 
institution a seat is still a big deal. This university still has a whole 
bunch of original IBM PCs in use (albeit networked) -- good enough for 
WordPerfect.

|> >NT will (initially) be only a single-user OS. The multi-user protection 
|> >provides the advantage of isolating users from each other and isolating 
|> >system configuration data from user configuration data. For example, our 
|> >workgroup has a couple of PCs in a commonly accessible location for use 
|> >by anybody in the group. These PCs are routinely getting messed up because 
|> >each user moves things around to suit his/herself. Protected user profiles 
|> >will provide a more consistent environment for the users of these PCs.
|> 
|> It's a nice concept as long as nobody needs the computer for very
|> much.  If you've more than one person who needs lots of computer time,
|> a shared workstation very quickly loses any and all value.

In our workgroup everybody has a PC and workstation in his/her office. 
The central resources (PCs and workstations) represent special equipment 
which cannot be duplicated on a per office basis. I think that you're alluding
to one of Pournelle's Laws -- at least one CPU per person.

Jon Mellott
(jon@alpha.ee.ufl.edu)
Newsgroups: comp.os.ms-windows.advocacy,comp.os.os2.advocacy