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

[Owen Lewis]

----- Original Message -----
From: "Brian Gladman" <brg@gladman.plus.com>
To: "UK Crypto Posting" <stevee+brg@slimy.greenend.org.uk>
Sent: 05 February 2001 10:58
Subject: Re: Why "carnivore" type systems can't be (entirely) open source


> This debate is getting unmanageable so I am cutting out the existing text
in> order to get back to the key point.

(snip)

Fair enough. Let's refer to the thread subject line, where it all began. I
believe that Richard could well prove correct in his prognostication,
despite the rejoinder from several list members that he was advocating the
dreaded STO.

Over several exchanges we have established that you yourself only object to
the use of STO when it is used by A to deny access to B to the algorithm and
coding of a cipher provided by A for the use of B. In this particular, you
consider STO anathema but in other applications you also see the value of
it. For my part, even in the particular that you object to, I see room for
benign use of STO as well as malign exploitation of B by A. I have personal
knowledge of several examples of benign use of STO and I am surprised that
you do not have much the same experience.

In the specific of the GSM system, introduced into this thread by Ben as an
example of  how damaging to B is the use of STO by A, I have shown as best I
can that :

        -    It is entirely wrong to consider GSM as a secure system. It
provides conditional privacy only and can do no more, because of its very
operational parameters. This would be true whatever cipher was used,
concealed or declared. The cipher is very far from the weakest link in GSM's
security chain and improving the cipher and declaring it could not make GSM,
as a system, appreciably more secure.

        -    Despite the conditional nature of the privacy afforded to B in
GSM, B has flocked en masse to the system and finds that, in the main, the
level of privacy provided suits his need.   That you and some others
vehemently disagree with B in this matter has not influenced B's desire to
adopt GSM in the least. It is B's wishes and none other than has determined
both the past success and assured the future of GSM type cellular wireless
telecom system design.

STO is an old saw. However, sometimes even an old saw can be employed to
fine effect by a skilled craftsman. There really has been no more to this
discussion than is contained in the two preceding sentences..

Owen