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[school-discuss] Re: Re: Re: Passwords for kids? [straying off topic]



on Mon, May 17, 2004 at 11:46:51AM -0700, Ian Paterson (ipaterson@shaw.ca) wrote:
> Karsten M. Self wrote:
> >on Sun, May 16, 2004 at 10:52:36PM -0700, Ian Paterson (ipaterson@shaw.ca) 
> >wrote:
> >
> >>Karsten M. Self wrote:

> >>>>>But for a fair number of 'em, particulary the younger set, and a few
> >>>>>others with learning disabilities, remembering passwords seems to be
> >>>>>beyond the possible.  Anyone have experience with setting up accounts
> >>>>>for kids?
> >>>>
> >>>>I suppose you could go for a biometric solution
> >>
> >>How about using floppy disks as hardware ID tokens? 

> >No floppy drives on the systems.

> >These kids would likely be putting the disks in pockets, backpacks, etc.
> >I'd like to minimize opportunities for foreign material introduction to
> >these systems.
> 
> Do you mean malicious software hitching a ride on a floppy disk? Or dirt 
> and grime wrecking your hardware? 'Cause if it's the former.... *points 
> to the 'net*

Physical harm to hardware.

An additional issue has surfaced with degraded CD/DVD drives.  I've
incorporated the "no damaged disks" message.

Bits of silver flaking off at a few hundred RPM inside a case strikes me
as less than ideal.
 
> >Otherwise:  yes, this is a decent suggestion.  Assuming you can trust
> >the disk not to get compromised once on the system (either
> >overwriting the disk, or copying the keys).
> 
> Yeah. Overwriting the disk can be prevented somewhat by explaining the 
> overwrite tab and encouraging users to keep it in the upwards position, 
> but copying of keys (disks) isn't as easy to defend against.
> 
> What did Sierra and Apogee end up doing when they shipped their games on 
> disk? Does anyone remember a scheme that wasn't broken that could 
> protect the contents of the disk from being copied? 

Someone covers this in a discussion of Steve Wozniak, and I'm trying to
remember whom.  Possibly Phil Zimmerman.  There's never been a software
copy-prevention scheme he hasn't cracked, IIRC.


[USB pen drives...]

> True, but they have more capability than you'd want. Floppy disks are 
> prevalent enough that you can get them free nowadays since they're 
> useless to most people, whereas even an 32meg USB [key/pen] drive still 
> has it's uses for transferring small documents and the like. 

Getting Floppy drives on newer HW (particularly laptops) is becoming
sketchy.


> >Domain authentication is basically "single sign-on".  You authenticate
> >to a domain server.  Similar to Kerberos, etc.  The server validates you
> >and is what permits you to log on to _both_ the domain (and its
> >resources such as shares and printers), _and_ the local workstation.
> 
> Off topic: Similar to, or is Kerberos? Ghosts of threads gone by are 
> haunting my memories have what was borrowed where.

More or less directly identical to a legacy MS Windows domain log-on.
As that's what Samba does.

Kerberos IIRC uses a key and keyserver.  RTFM if you need the gritty
details.

 
> >What I've got set up has user profiles, *wants* to have a "group
> >profile" (essentially:  one place where I can add/remove items from
> >desktops, menues, bookmarks, etc.), uses Samba as a primary domain
> >controller, and *doesn't* utilize AD/LDAP.
> 
> >>Now when someone wants to use a computer to, say, write a biography on 
> >>Clifford Cocks, they sit down at any workstation and *either* type in 
> >>their user name and password, *or*, they can put in their personalized 
> >>floppy disk which contains their ID/certificate that corresponds to 
> >>their account. This way, you have the option of bypassing passwords if 
> >>you hold the unique ID/certificate (in this case, our floppy disk), 
> >>otherwise you can just log in with a user name and password without 
> >>needing to keep track of the floppy.
> >
> >
> >The weakness is that the certificate itself is sufficient.  If it's
> >obtained by Eve, she can crack into the system.
> 
> No, she can 'illegally' access a single user's account. Which shouldn't 
> be trusted anyways.

That was more or less what I'd said.  There are additional elements
which make this something to be avoided if possible.

 
> >This, incidentally, is the same weakness of most biometrics.
> >The difference is that you can revoke and issue new keys (certificates).
> >
> >Grafting a new set of fingerprints, irises, or DNA sequences onto me is
> >rather more problematic.
> 
> And somewhat more painful. Although anyone who's ever generated SSL 
> certs by hand might have reason to disagree...

If you want to insist on making it a fair comparison, please rip out and
exchange your eyeballs, and give me a complete comparative report by
Tuesday.

Biometrics have some rather weak points.

 
> *shrug*. In a professional setting I'd motion for a company policy to
> just fire the people who still have passwords on sticky notes, but
> with the situation as it stands now, you have to ask yourself if a
> physical identifier required to sign in is less secure or more secure
> than users remembering passwords by telling their friends.

Unfortunately, likelihood of stickies seems to increase as you climb the
corporate structure (with few notable exceptions).  I think the real
lesson is that security is hard, and people won't remember passwords.
 


> >The main problem is that [in a floppy-is-your-access-key system] the
> >token isn't _bound_ to the medium.  Copying the key breaks the
> >system.
> 
> Agreed, but this is a weakness that exists for user names, PIN numbers, 
> face recognition, credit cards, etc.. 

Keys bound to a person's head (a short, memorable passphrase), and/or
not available with high latency on the system, are far less likely to be
compromised.  Floppies just weren't built for this.

> Come to think of it, the only difference between a system like this
> and credit cards is the relative obscurity of consumer hardware
> readers/scanners.

Debit cards are protected by a secondary key:  your PIN.

Credit cards are protected by a _pretty_ effective rapid-response
system.  Having worked directly in the field:  it's possible to disable
a card in a matter of minutes.

In _both_ cases, the risk is a readily replaced commodity scaler (an
account balance).  Not a trove of complex data with deep trust
relationships and unknown consequences to compromise.


 
> What about a return to the cipher era and have a printed keyboard 
> overlay of some kind with a personalized set of instructions on which 
> buttons to press and in what order? Just a simple piece of paper that 
> had lines indicating the keys, which could be coloured or whatnot.

There have been several recent suggestions for "click the icons/pictures
in a known sequence" authentication schemes.  These would be good
particularly for kids.  However they're also likley to be closely bound
to a specific implmenentation.  Userid/password is readily identified
across a broad set of domains.



As a postscript:  I've been using a set of "favorites" (what's your
favorite ...), selecting mutiple questions, to generate passwords.  This
has turned out to be a pretty reliable method, the kids remember their
passwords, and if they don't, I just ask "what's your favorite..." and
they remember.  Well, except for a few of the six year olds.

But with well over 200 accounts, I've only got a small handful (Skil-Saw
handful as I call it...) who can't reliably log in.


Peace.

-- 
Karsten M. Self <kmself@ix.netcom.com>        http://kmself.home.netcom.com/
 What Part of "Gestalt" don't you understand?
    Vote Bush in '04: Because dictatorship is easier

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