Secret Key protection (was Re: PKI creed)

[Brian Gladman]

From: "Carl Ellison" <cme@acm.org>
To: <ukcrypto@maillist.ox.ac.uk>
Sent: Saturday, September 16, 2000 4:57 PM
Subject: Secret Key protection (was Re: PKI creed)


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> At 11:40 AM 9/15/00 +0100, Brian Gladman wrote:
> >The problem with this is not the public keys, since the keys we have
> >exchanged do not need to be public - it is the secret keys, since we are
> >depending on their long term secrecy.  And here I am not convinced that
we
> >have the technology to provide for this when these keys are being
> >manipulated by the sort of computer systems that we typically use at the
> >moment.
>
> Amen.
>
> It hit me the other day that when Diffie and Hellman were writing (and
> introduced the idea we now call non-repudiation) -- in 1976 -- computers
> were large, expensive corproate assets, kept in glass-walled rooms with
> raised floors and special air conditioning, with strong personnel access
> control on that room -- and were never loaded with software from a
Microsoft
> Word attachment or an Active-X plug-in.  In fact, purchase and
installation
> of software was a major undertaking, performed by the system
administration
> staff.
>
> Under those conditions, it was reasonable to think of computers as
properly
> speaking for the registered owner of the computer.
>
> >It will be some years before internet connected home PCs will be able to
> >sustain such levels of secrecy and this means that someone will have to
> >underwrite the resulting risks if e-commerce from home is to take off.
>
> If we plot such security measures versus time and look at the trend, we
> don't see computers becoming more secure over time -- they become less
> secure.  What market force will change that (especially since the market
> (the consumer) hates security(*) and wants nothing to get in the way
between
> him and his dancing pigs)?

I can only agree with you. In my view e-commerce will grow in spite of the
difficulties and my hope (maybe an unrealistic one) is that as fraud grows
with it, the 'group' carrying the cost of this fraud will push for improved
security.

For this to happen we have to (a) ensure that the cost of fraud falls on a
group that is in a position to do something about it (has organisation and
money), and (b) ensure that what they do makes things better and not worse.

I admit this is quite a challenge.

The split between hardware and software suppliers is not going to help us
here as they are respectively trying to optimise their part of computer
systems design without much concern for overall systems performance.  This
is bad generally but is a disaster for security.

If anyone doubts this phenomenon, I have recently plotted the time it takes
from turning my computer on to first being able to use it for all the
personal computers I have owned since the mid 1970s. Despite the
unbelievable increase in the power of my current home PC (dual 800MHz PIII
running Windws 2000) when compared to my first home PC (Sharp MZ80K) it
actually takes longer now than it did in the 1970s.

    Brian