Why "carnivore" type systems can't be (entirely) open source

[Owen Lewis]

----- Original Message -----
From: "Brian Gladman" <brg@gladman.plus.com>
To: <ukcrypto@chiark.greenend.org.uk>
Sent: 02 February 2001 12:43
Subject: Re: Why "carnivore" type systems can't be (entirely) open source


> > My 'case' is not based on GSM. However, since Ben introduced GSM into
the
> > discussion, it was convenient to make an example with it.
>
> The more important point here is that STO in this case was being used to
> protect a deliberate 'designed in' insecurity.

There is no dispute about that. My view is simply:

        -    Using a stronger cipher would have not materially increased the
the security offers by GSM (see posts passim and todays in response to Ross
re. Fiiji). It would also have required a change in te law of many countries
for it to be sold without restrictions as a consumer item.

        - The use of STO plus a medium grade cipher satisfied the system
providers requirements, legal requirements and also the expectations of the
mass market.

> It is hence a very good example of a typical use of STO.  I don't think
that
> anyone disputes the value of STO in hiding design insecurity and this is
> precisely why it is a completely discredited approach when the objective
is
> the opposite.

You either misunderstand or mis-describe the objective in GSM, both that of
need and of provision.

> Anyone who argues that security is enhanced by using STO to protect the
> 'security' available from deliberately broken cipher algorithms is
logically
> correct in certain circumstances but has clearly sold their soul to the
> devil.

Owen

(Drat! I've responded to this one before but will let this additional
response stand anyway.)